draft-ietf-cdni-control-triggers-02.txt   draft-ietf-cdni-control-triggers-03.txt 
Network Working Group R. Murray Network Working Group R. Murray
Internet-Draft B. Niven-Jenkins Internet-Draft B. Niven-Jenkins
Intended status: Standards Track Velocix (Alcatel-Lucent) Intended status: Standards Track Velocix (Alcatel-Lucent)
Expires: June 5, 2014 December 2, 2013 Expires: January 3, 2015 July 2, 2014
CDNI Control Interface / Triggers CDNI Control Interface / Triggers
draft-ietf-cdni-control-triggers-02 draft-ietf-cdni-control-triggers-03
Abstract Abstract
This document describes the part of the CDN Interconnect Control This document describes the part of the CDN Interconnect Control
Interface that allows a CDN to trigger activity in an interconnected Interface that allows a CDN to trigger activity in an interconnected
CDN that is configured to deliver content on its behalf. The CDN that is configured to deliver content on its behalf. The
upstream CDN can use this mechanism to request that the downstream upstream CDN can use this mechanism to request that the downstream
CDN pre-positions metadata or content, or that it re-validate or CDN pre-positions metadata or content, or that it re-validate or
purge metadata or content. The upstream CDN can monitor the status purge metadata or content. The upstream CDN can monitor the status
of activity that it has triggered in the downstream CDN. of activity that it has triggered in the downstream CDN.
Requirements Language Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119]. document are to be interpreted as described in RFC 2119 [RFC2119].
Status of this Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/. Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
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time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on June 5, 2014. This Internet-Draft will expire on January 3, 2015.
Copyright Notice Copyright Notice
Copyright (c) 2013 IETF Trust and the persons identified as the Copyright (c) 2014 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 5 1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4
2. Model for CDNI Triggers . . . . . . . . . . . . . . . . . . . 5 2. Model for CDNI Triggers . . . . . . . . . . . . . . . . . . . 5
2.1. Timing of Triggered Activity . . . . . . . . . . . . . . . 7 2.1. Timing of Triggered Activity . . . . . . . . . . . . . . 7
2.2. Trigger Results . . . . . . . . . . . . . . . . . . . . . 7 2.2. Trigger Results . . . . . . . . . . . . . . . . . . . . . 7
3. Collections of Trigger Status Resources . . . . . . . . . . . 7 3. Collections of Trigger Status Resources . . . . . . . . . . . 7
4. CDNI Trigger interface . . . . . . . . . . . . . . . . . . . . 8 4. CDNI Trigger interface . . . . . . . . . . . . . . . . . . . 8
4.1. Creating Triggers . . . . . . . . . . . . . . . . . . . . 9 4.1. Creating Triggers . . . . . . . . . . . . . . . . . . . . 9
4.2. Checking Status . . . . . . . . . . . . . . . . . . . . . 10 4.2. Checking Status . . . . . . . . . . . . . . . . . . . . . 11
4.2.1. Polling Trigger Status Resource collections . . . . . 11 4.2.1. Polling Trigger Status Resource collections . . . . . 11
4.2.2. Polling Trigger Status Resources . . . . . . . . . . . 11 4.2.2. Polling Trigger Status Resources . . . . . . . . . . 11
4.3. Deleting Triggers . . . . . . . . . . . . . . . . . . . . 11 4.3. Deleting Triggers . . . . . . . . . . . . . . . . . . . . 11
4.4. Expiry of Trigger Status Resources . . . . . . . . . . . . 12 4.4. Expiry of Trigger Status Resources . . . . . . . . . . . 12
4.5. Error Handling . . . . . . . . . . . . . . . . . . . . . . 12 4.5. Error Handling . . . . . . . . . . . . . . . . . . . . . 12
5. Properties of Triggers . . . . . . . . . . . . . . . . . . . . 13 5. Properties of Triggers . . . . . . . . . . . . . . . . . . . 13
5.1. Properties of Trigger Requests . . . . . . . . . . . . . . 13 5.1. Properties of Trigger Requests . . . . . . . . . . . . . 13
5.1.1. Content URLs . . . . . . . . . . . . . . . . . . . . . 14 5.1.1. Content URLs . . . . . . . . . . . . . . . . . . . . 14
5.2. Properties of Trigger Status Resources . . . . . . . . . . 14 5.2. Properties of Trigger Status Resources . . . . . . . . . 15
5.3. Properties of ErrorDesc . . . . . . . . . . . . . . . . . 15 5.3. Properties of ErrorDesc . . . . . . . . . . . . . . . . . 16
5.4. Properties of Trigger Collections . . . . . . . . . . . . 15 5.4. Properties of Trigger Collections . . . . . . . . . . . . 17
5.5. Trigger Resource Simple Data Type Descriptions . . . . . . 16 5.5. Trigger Resource Simple Data Type Descriptions . . . . . 17
5.5.1. TriggerType . . . . . . . . . . . . . . . . . . . . . 16 5.5.1. TriggerType . . . . . . . . . . . . . . . . . . . . . 17
5.5.2. TriggerStatus . . . . . . . . . . . . . . . . . . . . 16 5.5.2. TriggerStatus . . . . . . . . . . . . . . . . . . . . 18
5.5.3. URLs . . . . . . . . . . . . . . . . . . . . . . . . . 16 5.5.3. URLs . . . . . . . . . . . . . . . . . . . . . . . . 18
5.5.4. AbsoluteTime . . . . . . . . . . . . . . . . . . . . . 17 5.5.4. AbsoluteTime . . . . . . . . . . . . . . . . . . . . 18
5.5.5. ErrorCode . . . . . . . . . . . . . . . . . . . . . . 17 5.5.5. ErrorCode . . . . . . . . . . . . . . . . . . . . . . 18
6. JSON Encoding of Objects . . . . . . . . . . . . . . . . . . . 17 6. JSON Encoding of Objects . . . . . . . . . . . . . . . . . . 19
6.1. JSON Encoding of Embedded Types . . . . . . . . . . . . . 18 6.1. JSON Encoding of Embedded Types . . . . . . . . . . . . . 20
6.1.1. TriggerType . . . . . . . . . . . . . . . . . . . . . 18 6.1.1. TriggerType . . . . . . . . . . . . . . . . . . . . . 20
6.1.2. TriggerStatus . . . . . . . . . . . . . . . . . . . . 18 6.1.2. TriggerStatus . . . . . . . . . . . . . . . . . . . . 20
6.1.3. PatternMatch . . . . . . . . . . . . . . . . . . . . . 18 6.1.3. PatternMatch . . . . . . . . . . . . . . . . . . . . 20
6.1.4. ErrorDesc . . . . . . . . . . . . . . . . . . . . . . 19 6.1.4. ErrorDesc . . . . . . . . . . . . . . . . . . . . . . 21
6.1.5. ErrorCode . . . . . . . . . . . . . . . . . . . . . . 19 6.1.5. ErrorCode . . . . . . . . . . . . . . . . . . . . . . 22
6.1.6. Relationship . . . . . . . . . . . . . . . . . . . . . 19 6.2. MIME Media Types . . . . . . . . . . . . . . . . . . . . 22
6.1.7. Link Object . . . . . . . . . . . . . . . . . . . . . 20 7. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . 22
6.2. MIME Media Types . . . . . . . . . . . . . . . . . . . . . 20 7.1. Creating Triggers . . . . . . . . . . . . . . . . . . . . 23
7.1.1. Preposition . . . . . . . . . . . . . . . . . . . . . 23
7. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 7.1.2. Invalidate . . . . . . . . . . . . . . . . . . . . . 24
7.1. Creating Triggers . . . . . . . . . . . . . . . . . . . . 21 7.2. Examining Trigger Status . . . . . . . . . . . . . . . . 25
7.1.1. Preposition . . . . . . . . . . . . . . . . . . . . . 21 7.2.1. Collection of All Triggers . . . . . . . . . . . . . 25
7.1.2. Invalidate . . . . . . . . . . . . . . . . . . . . . . 22 7.2.2. Filtered Collections of Triggers . . . . . . . . . . 26
7.2. Examining Trigger Status . . . . . . . . . . . . . . . . . 23 7.2.3. Trigger Status Resources . . . . . . . . . . . . . . 28
7.2.1. Collection of All Triggers . . . . . . . . . . . . . . 24 7.2.4. Polling for Change . . . . . . . . . . . . . . . . . 30
7.2.2. Filtered Collections of Triggers . . . . . . . . . . . 25 7.2.5. Cancelling or Removing a Trigger . . . . . . . . . . 33
7.2.3. Trigger Status Resources . . . . . . . . . . . . . . . 26 7.2.6. Error Reporting . . . . . . . . . . . . . . . . . . . 35
7.2.4. Polling for Change . . . . . . . . . . . . . . . . . . 28 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 36
7.2.5. Cancelling or Removing a Trigger . . . . . . . . . . . 31 8.1. CI/T MIME Media Types . . . . . . . . . . . . . . . . . . 36
7.2.6. Error Reporting . . . . . . . . . . . . . . . . . . . 33 9. Security Considerations . . . . . . . . . . . . . . . . . . . 36
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 34 9.1. Authentication, Confidentiality, Integrity Protection . . 36
8.1. CI/T MIME Media Types . . . . . . . . . . . . . . . . . . 35 9.2. Denial of Service . . . . . . . . . . . . . . . . . . . . 37
9. Security Considerations . . . . . . . . . . . . . . . . . . . 35 10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 37
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 35 11. References . . . . . . . . . . . . . . . . . . . . . . . . . 37
11. References . . . . . . . . . . . . . . . . . . . . . . . . . . 35 11.1. Normative References . . . . . . . . . . . . . . . . . . 37
11.1. Normative References . . . . . . . . . . . . . . . . . . . 35 11.2. Informative References . . . . . . . . . . . . . . . . . 37
11.2. Informative References . . . . . . . . . . . . . . . . . . 36 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 38
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 36
1. Introduction 1. Introduction
[RFC6707] introduces the Problem scope for CDN Interconnection (CDNI) [RFC6707] introduces the Problem scope for CDN Interconnection (CDNI)
and lists the four categories of interfaces that may be used to and lists the four categories of interfaces that may be used to
compose a CDNI solution (Control, Metadata, Request Routing, compose a CDNI solution (Control, Metadata, Request Routing,
Logging). Logging).
[I-D.ietf-cdni-framework] expands on the information provided in [I-D.ietf-cdni-framework] expands on the information provided in
[RFC6707] and describes each of the interfaces and the relationships [RFC6707] and describes each of the interfaces and the relationships
skipping to change at page 4, line 30 skipping to change at page 4, line 4
are the "High" and "Medium" priority requirements for the CI are the "High" and "Medium" priority requirements for the CI
identified in section 4 of [I-D.ietf-cdni-requirements], reproduced identified in section 4 of [I-D.ietf-cdni-requirements], reproduced
here for convenience: here for convenience:
CI-1 [HIGH] The CDNI Control interface shall allow the Upstream CI-1 [HIGH] The CDNI Control interface shall allow the Upstream
CDN to request that the Downstream CDN, including downstream CDN to request that the Downstream CDN, including downstream
cascaded CDNs, delete an object or set of objects and/or its CDNI cascaded CDNs, delete an object or set of objects and/or its CDNI
metadata from the CDN surrogates and any storage. Only the metadata from the CDN surrogates and any storage. Only the
object(s) and CDNI metadata that pertain to the requesting object(s) and CDNI metadata that pertain to the requesting
Upstream CDN are allowed to be purged. Upstream CDN are allowed to be purged.
CI-2 [MED] The CDNI Control interface should allow for multiple CI-2 [MED] The CDNI Control interface should allow for multiple
content items identified by a Content Collection ID to be purged content items identified by a Content Collection ID to be purged
using a single Content Purge action. using a single Content Purge action.
CI-3 [MED] The CDNI Control interface should allow the Upstream CI-3 [MED] The CDNI Control interface should allow the Upstream
CDN to request that the Downstream CDN, including downstream CDN to request that the Downstream CDN, including downstream
cascaded CDNs, mark an object or set of objects and/or its CDNI cascaded CDNs, mark an object or set of objects and/or its CDNI
metadata as "stale" and revalidate them before they are delivered metadata as "stale" and revalidate them before they are delivered
again. again.
CI-4 [HIGH] The CDNI Control interface shall allow the Downstream CI-4 [HIGH] The CDNI Control interface shall allow the Downstream
CDN to report on the completion of these actions (by itself, and CDN to report on the completion of these actions (by itself, and
including downstream cascaded CDNs, in a manner appropriate for including downstream cascaded CDNs, in a manner appropriate for
the action (e.g. synchronously or asynchronously). The the action (e.g. synchronously or asynchronously). The
confirmation receipt should include a success or failure confirmation receipt should include a success or failure
indication. The failure indication along with the reason are used indication. The failure indication along with the reason are used
if the Downstream CDN cannot delete the content in its storage. if the Downstream CDN cannot delete the content in its storage.
CI-5 [MED] The CDNI Control interface should support initiation CI-5 [MED] The CDNI Control interface should support initiation
and control by the Upstream CDN of pre-positioned CDNI metadata and control by the Upstream CDN of pre-positioned CDNI metadata
acquisition by the Downstream CDN. acquisition by the Downstream CDN.
CI-6 [MED] The CDNI Control interface should support initiation CI-6 [MED] The CDNI Control interface should support initiation
and control by the Upstream CDN of pre-positioned content and control by the Upstream CDN of pre-positioned content
acquisition by the Downstream CDN. acquisition by the Downstream CDN.
o Section 2 outlines the model for the CI/T Interface at a high o Section 2 outlines the model for the CI/T Interface at a high
level. level.
o Section 3 describes collections of Trigger Resources. o Section 3 describes collections of Trigger Resources.
o Section 4 defines the RESTful web service provided by dCDN.
o Section 4 defines the web service provided by the dCDN.
o Section 5 lists properties of Trigger Requests and Status o Section 5 lists properties of Trigger Requests and Status
Resources. Resources.
o Section 6 defines a JSON encoding for Trigger Requests and Status o Section 6 defines a JSON encoding for Trigger Requests and Status
Resources. Resources.
o Section 7 contains example messages. o Section 7 contains example messages.
1.1. Terminology 1.1. Terminology
This document reuses the terminology defined in [RFC6707]. This document reuses the terminology defined in [RFC6707].
2. Model for CDNI Triggers 2. Model for CDNI Triggers
A trigger, sent from uCDN to dCDN, is a request for dCDN to do some A trigger, sent from the uCDN to the dCDN, is a request for dCDN to
work relating to data originating from uCDN. do some work relating to data originating from the uCDN.
The trigger may request action on either metadata or content, the The trigger may request action on either metadata or content, the
following actions can be requested: following actions can be requested:
o preposition - used to instruct dCDN to fetch metadata from uCDN, o preposition - used to instruct the dCDN to fetch metadata from the
or content from any origin including uCDN. uCDN, or content from any origin including the uCDN.
o invalidate - used to instruct dCDN to revalidate specific metadata
or content before re-using it. o invalidate - used to instruct the dCDN to revalidate specific
o purge - used to instruct dCDN to delete specific metadata or metadata or content before re-using it.
o purge - used to instruct the dCDN to delete specific metadata or
content. content.
The CI/T interface is a RESTful web service offered by dCDN. It The CI/T interface is a web service offered by the dCDN. It allows
allows creation and deletion of triggers, and tracking of the creation and deletion of triggers, and tracking of the triggered
triggered activity. When dCDN accepts a trigger it creates a activity. When the dCDN accepts a trigger it creates a resource
resource describing status of the triggered activity, a Trigger describing status of the triggered activity, a Trigger Status
Status Resource. The uCDN may poll Trigger Status Resources to Resource. The uCDN MAY poll Trigger Status Resources to monitor
monitor progress. progress.
Requests to invalidate and purge metadata or content apply to all Requests to invalidate and purge metadata or content apply to all
variants of that data with a given URI. variants of that data with a given URI.
The dCDN maintains a collection of Trigger Status Resources for each The dCDN maintains a collection of Trigger Status Resources for each
uCDN, each uCDN only has access to its own collection and the uCDN, each uCDN only has access to its own collection and the
location of that collection is shared when CDN interconnection is location of that collection is shared when CDN interconnection is
established. established.
To trigger activity in dCDN, uCDN will POST to the collection of To trigger activity in the dCDN, the uCDN will POST to the collection
Trigger Status Resources. If dCDN accepts the trigger, it creates a of Trigger Status Resources. If the dCDN accepts the trigger, it
new Trigger Status Resource and returns its location to uCDN. To creates a new Trigger Status Resource and returns its location to the
monitor progress, uCDN may GET the Trigger Status Resource. To uCDN. To monitor progress, the uCDN MAY GET the Trigger Status
cancel a trigger, or remove a trigger from the collection once its Resource. To cancel a trigger, or remove a trigger from the
activity has been completed, uCDN may DELETE the Trigger Status collection once its activity has been completed, the uCDN MAY DELETE
Resource. the Trigger Status Resource.
In addition to the collection of all Trigger Status Resources for In addition to the collection of all Trigger Status Resources for
uCDN, uCDN shall have access to filtered views of that collection. uCDN, uCDN has access to filtered views of that collection. These
These filtered views are defined in Section 3 and include collections filtered views are defined in Section 3 and include collections of
of active and completed triggers. These collections provide a active and completed triggers. These collections provide a mechanism
mechanism for polling the status of multiple jobs. for polling the status of multiple jobs.
Figure 1 is an example showing the basic message flow used by the Figure 1 is an example showing the basic message flow used by the
uCDN to trigger activity in dCDN, and for uCDN to discover the status uCDN to trigger activity in dCDN, and for uCDN to discover the status
of that activity. Only successful triggering is shown. Examples of of that activity. Only successful triggering is shown. Examples of
the messages are given in Section 7. the messages are given in Section 7.
uCDN dCDN uCDN dCDN
| (1) POST http://dcdn.example.com/triggers/uCDN | | (1) POST http://dcdn.example.com/triggers/uCDN |
[ ] --------------------------------------------------> [ ]--+ [ ] --------------------------------------------------> [ ]--+
| [ ] | (2) | [ ] | (2)
| (3) HTTP 201 Response [ ]<-+ | (3) HTTP 201 Response [ ]<-+
[ ] <-------------------------------------------------- [ ] [ ] <-------------------------------------------------- [ ]
| Loc: http://dcdn.example.com/triggers/uCDN/123 | | Loc: http://dcdn.example.com/triggers/uCDN/123 |
| | | |
. . . . . .
. . . . . .
skipping to change at page 6, line 43 skipping to change at page 6, line 31
| [ ] | [ ]
| (5) HTTP 200 Trigger Status Resource [ ] | (5) HTTP 200 Trigger Status Resource [ ]
[ ] <-------------------------------------------------- [ ] [ ] <-------------------------------------------------- [ ]
| | | |
| | | |
Figure 1: Basic CDNI Message Flow for Triggers Figure 1: Basic CDNI Message Flow for Triggers
The steps in Figure 1 are: The steps in Figure 1 are:
1. uCDN triggers action in dCDN by posting to a collection of 1. uCDN triggers action in the dCDN by posting to a collection of
Trigger Status Resources, Trigger Status Resources, "http://dcdn.example.com/triggers/
"http://dcdn.example.com/triggers/uCDN". The URL of this was uCDN". The URL of this was given to the uCDN when the trigger
given to uCDN when the trigger interface was established. interface was established.
2. dCDN authenticates the request, validates the trigger and if it 2. dCDN authenticates the request, validates the trigger and if it
accepts the request, creates a new Trigger Status Resource. accepts the request, creates a new Trigger Status Resource.
3. dCDN responds to uCDN with an HTTP 201 response status, and the
location of the Trigger Status Resource.
4. uCDN may repeatedly poll the Trigger Status Resource in dCDN. 3. dCDN responds to the uCDN with an HTTP 201 response status, and
the location of the Trigger Status Resource.
4. uCDN may repeatedly poll the Trigger Status Resource in the dCDN.
5. dCDN responds with the Trigger Status Resource, describing 5. dCDN responds with the Trigger Status Resource, describing
progress or results of the triggered activity. progress or results of the triggered activity.
The remainder of this document describes the messages, Trigger Status The remainder of this document describes the messages, Trigger Status
Resources, and collections of Trigger Status Resources in more Resources, and collections of Trigger Status Resources in more
detail. detail.
2.1. Timing of Triggered Activity 2.1. Timing of Triggered Activity
Timing of triggered activity is under dCDN control, including its Timing of triggered activity is under the dCDN's control, including
start-time and pacing of the activity in the network. its start-time and pacing of the activity in the network.
Invalidate and purge triggers MUST be applied to all data acquired Invalidate and purge triggers MUST be applied to all data acquired
before the trigger was created in dCDN. The dCDN MAY apply the before the trigger was created in the dCDN. The dCDN may apply the
triggers to data acquired after trigger creation. triggers to data acquired after trigger creation.
If uCDN wishes to invalidate or purge content, then immediately If the uCDN wishes to invalidate or purge content, then immediately
preposition replacement content at the same URLs, it must ensure the pre-position replacement content at the same URLs, it SHOULD ensure
dCDN has completed the invalidate/purge before initiating the the dCDN has completed the invalidate/purge before initiating the
prepositioning. If it fails to do that and the requests overlap, and prepositioning. Otherwise, the dCDN may pre-position the new content
dCDN passes the triggers on to a further dCDN in a cascade, that CDN then immediately invalidate or purge it (as a result of the two uCDN
may preposition content that has not yet been invalidated/purged in requests running in parallel).
its uCDN.
2.2. Trigger Results 2.2. Trigger Results
Each Trigger Request may operate on multiple data items. The trigger Each Trigger Request may operate on multiple data items. The trigger
shall be reported as "complete" only if all actions can be completed MUST NOT be reported as "complete" unless all actions can be
successfully, otherwise it shall be reported as "failed". The completed successfully, otherwise it MUST be reported as "failed" or
reasons for failure and URLs or Patterns affected shall be enumerated "processed". The reasons for failure and URLs or Patterns affected
in the Trigger Status Resource. For more detail, see section SHOULD be enumerated in the Trigger Status Resource. For more
Section 4.5. detail, see section Section 4.5.
If a dCDN is also acting as uCDN in a cascade, it MUST forward If a dCDN is also acting as a uCDN in a cascade, it MUST forward
triggers to any downstream CDNs that may have data affected by the triggers to any downstream CDNs that may have data affected by the
trigger. The trigger MUST NOT be reported as complete in a CDN until trigger. The trigger MUST NOT be reported as complete in a CDN until
it is complete in all of its downstream CDNs. A trigger MAY be it is complete in all of its downstream CDNs. A trigger MAY be
reported as failed as soon as it fails in a CDN or in any of its reported as failed as soon as it fails in a CDN or in any of its
downstream CDNs. downstream CDNs.
3. Collections of Trigger Status Resources 3. Collections of Trigger Status Resources
As described in Section 2, Trigger Status Resources exist in dCDN to As described in Section 2, Trigger Status Resources exist in dCDN to
report the status of activity triggered by each uCDN. report the status of activity triggered by each uCDN.
A collection of Trigger Status Resources is a resource that contains A collection of Trigger Status Resources is a resource that contains
a reference to each Trigger Status Resource in that collection. a reference to each Trigger Status Resource in that collection.
To trigger activity in dCDN, uCDN creates a new Trigger Status To trigger activity in the dCDN, the uCDN creates a new Trigger
Resource by posting to dCDN's collection of uCDN's Trigger Status Status Resource by posting to the dCDN's collection of uCDN's Trigger
Resources. The URL of each Trigger Status Resource is generated by Status Resources. The URL of each Trigger Status Resource is
the dCDN when it accepts the trigger, and returned to uCDN. This generated by the dCDN when it accepts the trigger, and returned to
immediately enables uCDN to check the status of that trigger. the uCDN. This immediately enables the uCDN to check the status of
that trigger.
The dCDN must present a different set of Trigger Status Resources to The dCDN MUST present a different set of Trigger Status Resources to
each interconnected uCDN, only Trigger Status Resources belonging to each interconnected uCDN. Trigger Status Resources belonging to a
a uCDN shall be visible to it. The dCDN may, for example, achieve uCDN MUST NOT be visible to any other client. The dCDN may, for
this by offering different collection URLs to uCDNs, or by filtering example, achieve this by offering different collection URLs to uCDNs,
the response based on the client uCDN. or by filtering the response based on the client uCDN.
The dCDN resource representing the collection of all uCDN's Trigger The dCDN resource representing the collection of all the uCDN's
Status Resources is accessible to uCDN. This collection lists all Trigger Status Resources is accessible to the uCDN. This collection
uCDN triggers that have been accepted by dCDN, and have not yet been lists all of the uCDN triggers that have been accepted by the dCDN,
deleted by uCDN or expired and removed by dCDN. and have not yet been deleted by the uCDN, or expired and removed by
the dCDN (as described in section Section 4.3).
In order to allow the uCDN to check status of multiple jobs in a
single request, the dCDN SHOULD also maintain collections
representing filtered views of the collection of all Trigger Status
Resources. The filtered collections are:
In order to allow uCDN to check status of multiple jobs in a single
request, dCDN shall also maintain collections representing filtered
views of the collection of all Trigger Status Resources. The
filtered collections are:
o Pending - Trigger Status Resources for triggers that have been o Pending - Trigger Status Resources for triggers that have been
accepted, but not yet acted upon. accepted, but not yet acted upon.
o Active - Trigger Status Resources for triggered activity that is o Active - Trigger Status Resources for triggered activity that is
currently being processed in dCDN. currently being processed in the dCDN.
o Complete - Trigger Status Resources representing activity that o Complete - Trigger Status Resources representing activity that
completed successfully. completed successfully, or for which no further status updates
will be made by the dCDN.
o Failed - Trigger Status Resources representing activity that o Failed - Trigger Status Resources representing activity that
failed. failed.
4. CDNI Trigger interface 4. CDNI Trigger interface
This section describes an interface to enable an upstream CDN to This section describes an interface to enable an upstream CDN to
trigger defined activities in a downstream CDN. The interface is trigger defined activities in a downstream CDN. The interface is
intended to be independent of the set of activities defined now, or intended to be independent of the set of activities defined now, or
that may be defined in future. that may be defined in future.
CI/T is built on the principles of RESTful web services. Requests CI/T is built on the principles of RESTful web services. Requests
are made over HTTP, and the HTTP Method defines the operation the are made over HTTP, and the HTTP Method defines the operation the
request would like to perform. The corresponding HTTP Response request would like to perform. The corresponding HTTP Response
returns the status of the operation in the HTTP Status Code and returns the status of the operation in the HTTP Status Code and
returns the current representation of the resource (if appropriate) returns the current representation of the resource (if appropriate)
in the Response Body. HTTP Responses from servers implementing CI/T in the Response Body. HTTP Responses from servers implementing CI/T
that contain a response body SHOULD include an ETag to enable that contain a response body SHOULD include an ETag to enable
validation of cached versions of returned resources. validation of cached versions of returned resources.
Servers implementing CI/T MUST support the HTTP GET, HEAD, POST and Servers implementing CI/T MUST support the HTTP GET, HEAD, POST and
DELETE methods. The only representation specified in this document DELETE methods as defined in [RFC7231]. The only representation
is JSON. specified in this document is JSON, [RFC7159].
Trigger Requests are POSTed to a URI in dCDN. If the trigger is The URL of the dCDN's collections of Trigger Status Resources need to
accepted by dCDN, it creates a Trigger Status Resource and returns be either discovered by, or configured in, the uCDN. The mechanism
its URI to dCDN in an HTTP 201 response. The triggered activity can for discovery of those URLs is outside the scope of this document.
then be monitored by uCDN using that resource and the collections
described in Section 3.
The URI that Trigger Requests should be POSTed to needs to be either Trigger Requests are POSTed to the dCDN's collection of all Trigger
discovered by or configured in the upstream CDN. Performing a GET on Status Resources. If the trigger is accepted by the dCDN, it creates
that URI retrieves a collection of the URIs of all Trigger Status a new Trigger Status Resource and returns its URI to the dCDN in an
Resources. The URI of each Trigger Status Resource is also returned HTTP 201 response. The triggered activity can then be monitored by
to uCDN when it is created. This means all Trigger Status Resources the uCDN using that resource and the collections described in
can be discovered, so CI/T servers are free to assign whatever Section 3.
structure they desire to the URIs for CI/T resources. CI/T clients
MUST NOT make any assumptions regarding the structure of CI/T URIs or The URI of each Trigger Status Resource is returned to the uCDN when
the mapping between CI/T objects and their associated URIs. it is created. This means all Trigger Status Resources can be
Therefore any URIs present in the examples below are purely discovered, so CI/T servers are free to assign whatever structure
illustrative and are not intended to impose a definitive structure on they desire to the URIs for CI/T resources. CI/T clients MUST NOT
CI/T interface implementations. make any assumptions regarding the structure of CI/T URIs or the
mapping between CI/T objects and their associated URIs. Therefore
any URIs present in the examples below are purely illustrative and
are not intended to impose a definitive structure on CI/T interface
implementations.
The CI/T interface builds on top of HTTP, so CI/T servers may make The CI/T interface builds on top of HTTP, so CI/T servers may make
use of any HTTP feature when implementing the CI/T interface. For use of any HTTP feature when implementing the CI/T interface. For
example, a CI/T server may make use of HTTP's caching mechanisms to example, a CI/T server may make use of HTTP's caching mechanisms to
indicate that the returned response/representation has not been indicate that a requested response/representation has not been
modified since it was last returned, reducing the processing needed modified, reducing the processing needed to determine whether the
to determine whether the status of triggered activity has changed. status of triggered activity has changed.
This specification is neutral with regard to the transport below the This specification is neutral with regard to the transport below the
HTTP layer. HTTP layer.
Discovery of the CI/T Interface is outside the scope of this The dCDN MUST ensure that activity triggered by the uCDN only affects
document. It is anticipated that a common mechanism for discovery of
all CDNI interfaces will be defined.
The dCDN must ensure that activity triggered by uCDN only affects
metadata or content originating from that uCDN. Since only one CDN metadata or content originating from that uCDN. Since only one CDN
can be authoritative for a given item of metadata or content, this can be authoritative for a given item of metadata or content, this
requirement means there cannot be any "loops" in trigger requests requirement means there cannot be any "loops" in trigger requests
between CDNs. between CDNs.
4.1. Creating Triggers 4.1. Creating Triggers
To create a new trigger, uCDN makes an HTTP POST to the unfiltered To create a new trigger, the uCDN makes an HTTP POST to the
collection of its triggers. The request body of that POST is a unfiltered collection of its triggers. The request body of that POST
Trigger Request. is a Trigger Request.
dCDN validates and authenticates that request, if it is malformed or The dCDN validates and authenticates that request, if it is malformed
uCDN does not have sufficient access rights it MAY reject the request or the uCDN does not have sufficient access rights it MAY reject the
immediately. In this case, it SHALL respond with an appropriate 4xx request immediately. In this case, it MUST respond with an
HTTP error code and no resource shall be created on dCDN. appropriate 4xx HTTP error code and a resource MUST NOT be created on
dCDN.
If the request is accepted, uCDN SHALL create a new Trigger Status If the request is accepted, the uCDN MUST create a new Trigger Status
Resource. The HTTP response to dCDN SHALL have status code 201 and Resource. The HTTP response to the dCDN MUST have status code 201
the URI of the Trigger Status Resource in the Location header field. and the URI of the Trigger Status Resource in the Location header
The HTTP response MAY include the content of the newly created field. The HTTP response SHOULD include the content of the newly
Trigger Status Resource, this is recommended particularly in cases created Trigger Status Resource, this is recommended particularly in
where the trigger has completed immediately. cases where the trigger has completed immediately.
Once a Trigger Status Resource has been created dCDN MUST NOT re-use Once a Trigger Status Resource has been created the dCDN MUST NOT re-
its location, even after that resource has been removed through use its location, even after that resource has been removed.
deletion or expiry.
The "request" property of the Trigger Status Resource SHALL contain The "request" property of the Trigger Status Resource contains the
the information posted in the body of the Trigger Request. Note that information posted in the body of the Trigger Request. Note that
this need not be a byte-for-byte copy. For example, in the JSON this need not be a byte-for-byte copy. For example, in the JSON
representation the dCDN may re-serialise the information differently. representation the dCDN may re-serialise the information differently.
If the trigger is queued by dCDN for later action, the "status" If the dCDN is not able to track triggered activity, it MUST indicate
property of the Trigger Status Resource SHALL be "pending". Once that indicate that it has accepted the request but will not be
trigger processing has started the "status" SHALL be "active". providing further status updates. To do this, it sets the "status"
of the Trigger Status Resource to "processed". In this case, CI/T
processing should continue as for a "complete" request, so the
Trigger Status Resource MUST be added to the dCDN's collection of
Complete Triggers. The dCDN SHOULD also provide an estimated
completion time for the request, by using the "etime" property of the
Trigger Status Resource. This will allow the uCDN to schedule
prepositioning after an earlier delete of the same URLs is expected
to have finished.
A trigger may result in no activity in dCDN if, for example, it is an If the dCDN is able to track triggered activity, the trigger is
invalidate or purge request for data the dCDN has not acquired, or a queued by the dCDN for later action, the "status" property of the
prepopulate request for data it has already acquired. In this case, Trigger Status Resource MUST be "pending". Once trigger processing
the "status" of the Trigger Status Resource shall be "complete" and has started the "status" MUST be "active". Finally, once the
the Trigger Status Resource shall be added to the dCDN collection of triggered activity is complete, the trigger status MUST be set to
Complete Triggers. "complete" or "failed".
If dCDN is not able to track triggered activity, it MAY indicate that A trigger may result in no activity in the dCDN if, for example, it
it has undertaken to complete the activity but will not report is an invalidate or purge request for data the dCDN has not yet
completion or any further errors. To do this, it must set the acquired, or a prepopulate request for data it has already acquired
trigger status to "complete", with an estimated completion time in and which is still valid. In this case, the "status" of the Trigger
the future ("etime" greater than "mtime"). Status Resource MUST be "processed" or "complete", and the Trigger
Status Resource MUST be added to the dCDN's collection of Complete
Triggers.
Once created, Trigger Status Resources may be deleted by uCDN but not Once created, Trigger Status Resources may be deleted by the uCDN but
modified. The dCDN MUST reject PUT and POST requests from uCDN to not modified. The dCDN MUST reject PUT and POST requests from the
Trigger Status Resources using HTTP status code 403. uCDN to Trigger Status Resources using HTTP status code 403.
4.2. Checking Status 4.2. Checking Status
The uCDN has two ways to check progress of activity it has triggered The uCDN has two ways to check progress of activity it has triggered
in dCDN, described in the following sections. in the dCDN, described in the following sections.
Because the triggers protocol is based on HTTP, Entity Tags may be To check for change in status of a resource or collection of
used by the uCDN as cache validators, as defined in section 3.11 of resources without re-fetching the whole resource or collection,
[RFC2616], to check for change in status of a resource or collection Entity Tags SHOULD be used by the uCDN as cache validators, as
of resources without re-fetching the whole resource or collection. defined in [RFC7232].
The dCDN should use the cache control headers for responses to GETs The dCDN SHOULD use the cache control headers for responses to GETs
for Trigger Status Resources and Collections to indicate the for Trigger Status Resources and Collections to indicate the
frequency at which it recommends uCDN should poll for change. frequency at which it recommends uCDN should poll for change.
4.2.1. Polling Trigger Status Resource collections 4.2.1. Polling Trigger Status Resource collections
uCDN can fetch the collection of its Trigger Status Resources, or The uCDN can fetch the collection of its Trigger Status Resources, or
filtered views of that collection. filtered views of that collection.
This makes it possible to poll status of all triggered activity in a This makes it possible to poll status of all triggered activity in a
single request. If dCDN moves a Trigger Status Resource from the single request. If the dCDN moves a Trigger Status Resource from the
Active to the Completed collection, uCDN may chose to fetch the Active to the Completed collection, the uCDN may chose to fetch the
result of that activity. result of that activity.
When polling in this way, uCDN may choose to use HTTP Entity Tags to When polling in this way, the uCDN SHOULD use HTTP Entity Tags to
monitor for change, rather than repeatedly fetching the whole monitor for change, rather than repeatedly fetching the whole
collection. collection.
4.2.2. Polling Trigger Status Resources 4.2.2. Polling Trigger Status Resources
uCDN has a reference (URI provided by the dCDN) for each Trigger The uCDN has a reference (URI provided by the dCDN) for each Trigger
Status Resource it has created, it may fetch that resource at any Status Resource it has created, it may fetch that resource at any
time. time.
This may be used to retrieve progress information, and to fetch the This MAY be used to retrieve progress information, and to fetch the
result of triggered activity. result of triggered activity.
4.3. Deleting Triggers 4.3. Deleting Triggers
The uCDN MAY delete Trigger Status Resources at any time, using the The uCDN MAY delete Trigger Status Resources at any time, using the
HTTP DELETE method. HTTP DELETE method.
Once deleted, the references to a Trigger Status Resource MUST be Once deleted, the references to a Trigger Status Resource MUST be
removed from all Trigger Status Resource collections. Subsequent removed from all Trigger Status Resource collections. Subsequent
requests for the resource shall be handled as required by HTTP, and requests for the resource MUST be handled as required by HTTP, and so
so will receive responses with status 404 or 410. will receive responses with status 404 or 410.
If a "pending" Trigger Status Resource is deleted, dCDN SHOULD NOT If a "pending" Trigger Status Resource is deleted, the dCDN SHOULD
start processing of that activity. Deleting a "pending" trigger does NOT start processing of that activity. Deleting a "pending" trigger
not however guarantee that it is not started because, once it has does not however guarantee that it is not started because the uCDN
triggered activity, uCDN cannot control the timing of that activity. cannot control the timing of that activity. Processing may, for
Processing may, for example, start after the DELETE is sent by uCDN example, start after the DELETE is sent by the uCDN but before the
and before the DELETE is processed by dCDN. DELETE is processed by the dCDN.
If an "active" Trigger Status Resource is deleted, dCDN MAY stop If an "active" Trigger Status Resource is deleted, the dCDN MAY stop
processing the triggered activity. However, as with deletion of a processing the triggered activity. However, as with deletion of a
"pending" trigger, dCDN does not guarantee this. "pending" trigger, the dCDN does not guarantee this.
Deletion of a "complete" or "failed" Trigger Status Resource requires Deletion of a "complete", "processed" or "failed" Trigger Status
no processing in dCDN other than deletion of the resource. Resource requires no processing in the dCDN other than deletion of
the resource.
4.4. Expiry of Trigger Status Resources 4.4. Expiry of Trigger Status Resources
The dCDN MAY choose to automatically delete Trigger Status Resources The dCDN MAY choose to automatically delete Trigger Status Resources
some time after they become completed or failed. In this case, dCDN some time after they become "complete", "processed" or "failed". In
will remove the resource and respond to subsequent requests for it this case, the dCDN will remove the resource and respond to
with HTTP status 404 or 410. subsequent requests for it with HTTP status 404 or 410.
If dCDN performs this housekeeping, it MUST have reported the length If the dCDN performs this housekeeping, it MUST have reported the
of time after which completed Trigger Status Resources become stale length of time after which completed Trigger Status Resources become
via a property of the collection of all Trigger Status Resources. It stale via a property of the collection of all Trigger Status
is recommended that Trigger Status Resources are automatically Resources. It is recommended that Trigger Status Resources are not
deleted 24 hours after they become completed or failed. automatically deleted for at least 24 hours after they become
"complete", "processed" or "failed".
To ensure it has access to the status of its completed and failed To ensure it has access to the status of its completed and failed
triggers, it is recommended that uCDN's polling interval is half the triggers, it is recommended that the uCDN's polling interval is half
time after which records for completed activity will be considered the time after which records for completed activity will be
stale. considered stale.
4.5. Error Handling 4.5. Error Handling
A CI/T server may reject a trigger request using HTTP status codes, A CI/T server may reject a trigger request using HTTP status codes.
for example 400 if the request is malformed or 401 if the client does For example, 400 if the request is malformed, or 401 if the client
not have permission to create triggers or it is trying to act on does not have permission to create triggers or it is trying to act on
another CDN's data. another CDN's data.
If any part of the trigger request fails the trigger shall be If any part of the trigger request fails, the trigger SHOULD be
reported as "failed" once its activity is complete, or if no further reported as "failed" once its activity is complete or if no further
errors will be reported. The "errors" property in the Trigger Status errors will be reported. The "errors" property in the Trigger Status
Resource will be used to enumerate which actions failed and the Resource will be used to enumerate which actions failed and the
reasons for failure, and may be present while the trigger is still reasons for failure, and may be present while the trigger is still
"pending" or "active" if the trigger is still running for some URLs "pending" or "active", if the trigger is still running for some URLs
or Patterns in the trigger request. or Patterns in the trigger request.
Once a request has been accepted, processing errors are reported in Once a request has been accepted, processing errors are reported in
the Trigger Status Resource using a list of "ErrorDesc". Each the Trigger Status Resource using a list of "ErrorDesc". Each
ErrorDesc is used to report errors against one or more of the URLs or ErrorDesc is used to report errors against one or more of the URLs or
Patterns in the trigger request. Patterns in the trigger request.
If a surrogate affected by a trigger is offline in dCDN, or dCDN is If a surrogate affected by a trigger is offline in the dCDN, or the
unable to pass a trigger request on to any of its affected dCDNs; dCDN is unable to pass a trigger request on to any of its cascaded
dCDN should report an error if the request is abandoned, otherwise it dCDNs; the dCDN SHOULD report an error if the request is abandoned.
must keep the trigger in state "pending" or "active" until it's acted Otherwise, it SHOULD keep the trigger in state "pending" or "active"
upon or uCDN chooses to cancel it. Or, if the request is queued and until it's acted upon or the uCDN chooses to cancel it. Or, if the
dCDN will not report further status, dCDN may report the trigger as request is queued and the dCDN will not report further status, the
"complete" with an "etime" in the future. dCDN MAY report the trigger as "processed", in which case it SHOULD
also provide an estimated completion time.
Note that an "invalidate" trigger may be reported as "complete" when Note that an "invalidate" trigger may be reported as "complete" when
surrogates that may have the data are offline, if those surrogates surrogates that may have the data are offline. In this case,
will not use the affected data without first revalidating it when surrogates MUST NOT use the affected data without first revalidating
they are back online. This does not apply to "preposition" or it when they are back online. This does not apply to "preposition"
"purge" triggers. or "purge" triggers.
5. Properties of Triggers 5. Properties of Triggers
5.1. Properties of Trigger Requests 5.1. Properties of Trigger Requests
Properties of Trigger Requests are defined in the following Properties of Trigger Requests are defined in the following
subsections. subsections.
Property: type Property: type
Description: This property defines the type of the trigger:
Description: This property defines the type of the trigger.
Type: TriggerType Type: TriggerType
Mandatory: Yes Mandatory: Yes
Property: metadata.urls Property: metadata.urls
Description: The uCDN URL for the metadata the trigger applies Description: The uCDN URL for the metadata the trigger applies
to. to.
Type: URLs Type: URLs
Mandatory: No, but at least one of 'metadata.*' or 'content.*' Mandatory: No, but at least one of 'metadata.*' or 'content.*'
MUST be present and non-empty. MUST be present and non-empty.
Property: content.urls Property: content.urls
Description: URLs of content data the trigger applies to, see Description: URLs of content data the trigger applies to, see
Section 5.1.1. Section 5.1.1.
Type: URLs Type: URLs
Mandatory: No, but at least one of 'metadata.*' or 'content.*' Mandatory: No, but at least one of 'metadata.*' or 'content.*'
MUST be present and non-empty. MUST be present and non-empty.
Property: content.ccid Property: content.ccid
Description: The Content Collection IDentifier of data the Description: The Content Collection IDentifier of data the
trigger applies to. trigger applies to.
Type: List of strings Type: List of strings
Mandatory: No, but at least one of 'metadata.*' or 'content.*' Mandatory: No, but at least one of 'metadata.*' or 'content.*'
MUST be present and non-empty. MUST be present and non-empty.
Property: metadata.patterns Property: metadata.patterns
Description: The metadata the trigger applies to. Description: The metadata the trigger applies to.
Type: List of PatternMatch Type: List of PatternMatch
Mandatory: No, but at least one of 'metadata.*' or 'content.*' Mandatory: No, but at least one of 'metadata.*' or 'content.*'
MUST be present and non-empty, and metadata.patterns MUST NOT MUST be present and non-empty, and metadata.patterns MUST NOT
be present if the TriggerType is Preposition. be present if the TriggerType is Preposition.
Property: content.patterns Property: content.patterns
Description: The content data the trigger applies to. Description: The content data the trigger applies to.
Type: List of PatternMatch Type: List of PatternMatch
Mandatory: No, but at least one of 'metadata.*' or 'content.*' Mandatory: No, but at least one of 'metadata.*' or 'content.*'
MUST be present and non-empty, and content.patterns MUST NOT be MUST be present and non-empty, and content.patterns MUST NOT be
present if the TriggerType is Preposition. present if the TriggerType is Preposition.
5.1.1. Content URLs 5.1.1. Content URLs
To refer to content in dCDN, uCDN must present URLs in the same form To refer to content in the dCDN, the uCDN MUST present URLs in the
clients will use to access content in that dCDN, after transformation same form clients will use to access content in that dCDN, after
to remove any surrogate-specific parts of a 302-redirect URL form. transformation to remove any surrogate-specific parts of a
By definition, it is always possible to locate content based on URLs 302-redirect URL form. By definition, it is always possible to
in this form. locate content based on URLs in this form.
If content URLs are transformed by an intermediate CDN in a cascade, If content URLs are transformed by an intermediate CDN in a cascade,
that intermediate CDN must transform URLs in trigger requests it that intermediate CDN MUST transform URLs in trigger requests it
passes to its dCDN. passes to its dCDN.
When processing trigger requests, CDNs SHOULD ignore the URL scheme When processing trigger requests, CDNs MUST ignore the URL scheme
(http or https) in comparing URLs. For example, for an invalidate or (http or https) in comparing URLs. For example, for an invalidate or
purge trigger, content may invalidated or purged regardless of the purge trigger, content MUST invalidated or purged regardless of the
protocol clients use to request it. protocol clients use to request it.
5.2. Properties of Trigger Status Resources 5.2. Properties of Trigger Status Resources
Property: trigger Property: trigger
Description: The properties of trigger request that created Description: The properties of trigger request that created
this record. this record.
Type: TriggerRequest Type: TriggerRequest
Mandatory: Yes Mandatory: Yes
Property: ctime Property: ctime
Description: Time at which the request was received by dCDN.
Time is local to dCDN, there is no requirement to synchronise Description: Time at which the request was received by the
clocks between interconnected CDNs. dCDN. Time is determined by the dCDN, there is no requirement
to synchronise clocks between interconnected CDNs.
Type: AbsoluteTime Type: AbsoluteTime
Mandatory: Yes Mandatory: Yes
Property: mtime Property: mtime
Description: Time at which the resource was last modified. Description: Time at which the resource was last modified.
Time is local to dCDN, there is no requirement to synchronise Time is determined by the dCDN, there is no requirement to
clocks between interconnected CDNs. synchronise clocks between interconnected CDNs.
Type: AbsoluteTime Type: AbsoluteTime
Mandatory: Yes Mandatory: Yes
Property: etime Property: etime
Description: Estimate of the time at which dCDN expects to
complete the activity. Time is local to dCDN, there is no Description: Estimate of the time at which the dCDN expects to
requirement to synchronise clocks between interconnected CDNs. complete the activity. Time is determined by the dCDN, there
is no requirement to synchronise clocks between interconnected
CDNs.
Type: AbsoluteTime Type: AbsoluteTime
Mandatory: No Mandatory: No
Property: status Property: status
Description: Current status of the triggered activity. Description: Current status of the triggered activity.
Type: TriggerStatus Type: TriggerStatus
Mandatory: Yes Mandatory: Yes
Property: errors Property: errors
Description: List of ErrorDesc. Description: List of ErrorDesc.
Mandatory: No. Mandatory: No.
5.3. Properties of ErrorDesc 5.3. Properties of ErrorDesc
An ErrorDesc object is used to report failure for URLs and patterns An ErrorDesc object is used to report failure for URLs and patterns
in a trigger request. in a trigger request.
Property: error Property: error
Type: ErrorCode. Type: ErrorCode.
Mandatory: Yes. Mandatory: Yes.
Property: metadata.urls, content.urls, metadata.patterns, Property: metadata.urls, content.urls, metadata.patterns,
content.patterns content.patterns
Description: Metadata and content references copied from the Description: Metadata and content references copied from the
trigger request. Only those URLs and patterns to which the trigger request. Only those URLs and patterns to which the
error applies shall be included in each property, but those error applies shall be included in each property, but those
URLs and patterns shall be exactly as they appear in the URLs and patterns MUST be exactly as they appear in the
request, dCDN must not generalise the URLs. (For example, if request, the dCDN must not generalise the URLs. (For example,
uCDN requests prepositioning of URLs if the uCDN requests prepositioning of URLs
"http://ucdn.example.com/a" and "http://ucdn.example.com/b", "http://ucdn.example.com/a" and "http://ucdn.example.com/b",
dCDN may not generalise its error report to Pattern the dCDN must not generalise its error report to Pattern
"http://ucdn.example.com/*"). "http://ucdn.example.com/*").
Mandatory: At least one of these properties is mandatory in Mandatory: At least one of these properties is mandatory in
each ErrorDesc. each ErrorDesc.
Property: description Property: description
Description: A String containing a human-readable description Description: A String containing a human-readable description
of the error. of the error.
Mandatory: No. Mandatory: No.
5.4. Properties of Trigger Collections 5.4. Properties of Trigger Collections
Property: links Property: triggers
Description: References to Trigger Status Resources in the
Description: Links to Trigger Status Resources in the
collection. collection.
Type: List of Relationships. Type: URLs.
Mandatory: Yes Mandatory: Yes
Property: staleresourcetime Property: staleresourcetime
Description: The length of time for which dCDN guarantees to
keep a completed Trigger Status Resource. After this time, Description: The length of time for which the dCDN guarantees
dCDN MAY delete the resource and all references to it from to keep a completed Trigger Status Resource. After this time,
the dCDN MAY delete the resource and all references to it from
collections. collections.
Type: Integer, time in seconds. Type: Integer, time in seconds.
Mandatory: Yes, in the collection of all Trigger Status Mandatory: Yes, in the collection of all Trigger Status
Resources if dCDN deletes stale entries. If the property is Resources if the dCDN deletes stale entries. If the property
present in the filtered collections, it MUST have the same is present in the filtered collections, it MUST have the same
value as in the collection of all Trigger Status Resources. value as in the collection of all Trigger Status Resources.
5.5. Trigger Resource Simple Data Type Descriptions 5.5. Trigger Resource Simple Data Type Descriptions
This section describes the simpler data types that are used for This section describes the simpler data types that are used for
properties of Trigger Status resources. properties of Trigger Status resources.
5.5.1. TriggerType 5.5.1. TriggerType
This type defines the type of action being triggered, permitted This type defines the type of action being triggered, permitted
actions are: actions are:
o Preposition - a request for dCDN to acquire metadata or content.
o Invalidate - a request for dCDN to invalidate metadata or content. o Preposition - a request for the dCDN to acquire metadata or
After servicing this request the dCDN will not use the specified content.
data without first re-validating it using, for example, an "If-
None-Match" HTTP request. The dCDN need not erase the associated o Invalidate - a request for the dCDN to invalidate metadata or
data. content. After servicing this request the dCDN will not use the
o Purge - a request for dCDN to erase metadata or content. After specified data without first re-validating it using, for example,
servicing the request, the specified data must not be held on an "If-None-Match" HTTP request. The dCDN need not erase the
dCDN. associated data.
o Purge - a request for the dCDN to erase metadata or content.
After servicing the request, the specified data MUST NOT be held
on dCDN.
5.5.2. TriggerStatus 5.5.2. TriggerStatus
This type describes the current status of a Trigger, possible values This type describes the current status of a Trigger, possible values
are: are:
o Pending - the trigger has not yet been acted upon. o Pending - the trigger has not yet been acted upon.
o Active - the trigger is currently being acted upon. o Active - the trigger is currently being acted upon.
o Complete - the triggered activity completed successfully, or the
trigger has been accepted and no further status update will be o Complete - the triggered activity completed successfully.
made.
o Processed - the trigger has been accepted and no further status
update will be made (may be used in cases where completion cannot
be confirmed).
o Failed - the triggered activity could not be completed. o Failed - the triggered activity could not be completed.
5.5.3. URLs 5.5.3. URLs
This type describes a set of references to metadata or content, it is This type describes a set of references to metadata or content, it is
simply a list of absolute URLs. simply a list of absolute URLs.
5.5.4. AbsoluteTime 5.5.4. AbsoluteTime
Times are expressed in seconds since the UNIX epoch. Times are expressed in seconds since the UNIX epoch.
5.5.5. ErrorCode 5.5.5. ErrorCode
This type is used by dCDN to report failures in trigger processing. This type is used by dCDN to report failures in trigger processing.
o EMETA - dCDN was unable to acquire metadata required to fulfil the o EMETA - the dCDN was unable to acquire metadata required to fulfil
request. the request.
o ECONTENT - dCDN was unable to acquire content (preposition
o ECONTENT - the dCDN was unable to acquire content (preposition
triggers only). triggers only).
o EPERM - uCDN does not have permission to trigger the requested
o EPERM - the uCDN does not have permission to trigger the requested
activity (for example, the data is owned by another CDN). activity (for example, the data is owned by another CDN).
o EREJECT - dCDN is not willing to fulfil the request (for example,
a preposition request for content at a time when dCDN would not
accept Request Routing requests from uCDN).
o ECDN - An internal error in dCDN or one of its downstream CDNs.
6. JSON Encoding of Objects o EREJECT - the dCDN is not willing to fulfil the request (for
example, a preposition request for content at a time when dCDN
would not accept Request Routing requests from uCDN).
This encoding is based on that described in [I-D.ietf-cdni-metadata], o ECDN - An internal error in the dCDN or one of its downstream
but has been reproduced here while metadata work is in progress. CDNs.
Once that work is complete, the authors would look to align with the
structure of the metadata draft and make reference to common 6. JSON Encoding of Objects
definitions as appropriate.
The encoding for a CI/T object is a JSON object containing a The encoding for a CI/T object is a JSON object containing a
dictionary of (key,value) pairs where the keys are the property dictionary of (key,value) pairs where the keys are the property
names, and the values are the associated property values. names, and the values are the associated property values.
The keys of the dictionary are the names of the properties associated The keys of the dictionary are the names of the properties associated
with the object and are therefore dependent on the specific object with the object and are therefore dependent on the specific object
being encoded (i.e. dependent on the MIME Media Type of the returned being encoded (i.e. dependent on the MIME Media Type of the returned
resource). Likewise, the values associated with each key are resource). Likewise, the values associated with each key are
dependent on the specific object being encoded (i.e. dependent on the dependent on the specific object being encoded (i.e. dependent on the
skipping to change at page 17, line 47 skipping to change at page 19, line 25
with the object and are therefore dependent on the specific object with the object and are therefore dependent on the specific object
being encoded (i.e. dependent on the MIME Media Type of the returned being encoded (i.e. dependent on the MIME Media Type of the returned
resource). Likewise, the values associated with each key are resource). Likewise, the values associated with each key are
dependent on the specific object being encoded (i.e. dependent on the dependent on the specific object being encoded (i.e. dependent on the
MIME Media Type of the returned resource). MIME Media Type of the returned resource).
The "trigger" property of the top level JSON object lists the The "trigger" property of the top level JSON object lists the
requested action. requested action.
Key: trigger Key: trigger
Description: An object specifying the trigger type and a set of Description: An object specifying the trigger type and a set of
data to act upon. data to act upon.
Type: A JSON object. Type: A JSON object.
Mandatory: Yes. Mandatory: Yes.
Object keys in JSON are case sensitive and therefore any dictionary Object keys in JSON are case sensitive and therefore any dictionary
key defined by this document (for example the names of CI/T object key defined by this document (for example the names of CI/T object
properties) MUST always be represented in lowercase. properties) MUST always be represented in lowercase.
In addition to the properties of an object, the following additional In addition to the properties of an object, the following additional
keys may be present. keys MAY be present.
Key: base Key: base
Description: Provides a prefix for any relative URLs in the Description: Provides a prefix for any relative URLs in the
object. This is similar to the XML base tag [XML-BASE]. If object. This is similar to the XML base tag [XML-BASE]. If
absent, all URLs in the remainder of the document must be absent, all URLs in the remainder of the document MUST be
absolute URLs. absolute URLs.
Type: URI Type: URI
Mandatory: No Mandatory: No
Key: links Key: _links
Description: The relationships of this object to other Description: The relationships of this object to other
addressable objects. addressable objects.
Type: Array of Relationships. Type: Array of Relationships.
Mandatory: Yes Mandatory: Yes
6.1. JSON Encoding of Embedded Types 6.1. JSON Encoding of Embedded Types
6.1.1. TriggerType 6.1.1. TriggerType
Key: type Key: type
Description: One of "preposition", "invalidate" or "purge". Description: One of "preposition", "invalidate" or "purge".
Type: string Type: string
6.1.2. TriggerStatus 6.1.2. TriggerStatus
Key: status Key: status
Description: One of "pending", "active", "failed", "complete" Description: One of "pending", "active", "failed", "complete"
Type: string Type: string
6.1.3. PatternMatch 6.1.3. PatternMatch
A PatternMatch is encoded as a JSON Object containing a string to A PatternMatch is encoded as a JSON Object containing a string to
match and flags describing the type of match. match and flags describing the type of match.
Key: pattern Key: pattern
Description: A pattern for string matching. The pattern may Description: A pattern for string matching. The pattern may
contain the wildcards * and ?, where * matches any sequence of contain the wildcards * and ?, where * matches any sequence of
characters (including the empty string) and ? matches exactly characters (including the empty string) and ? matches exactly
one character. The three literals \ , * and ? should be one character. The three literals \ , * and ? MUST be escaped
escaped as \\, \* and \? as \\, \* and \?
Type: String Type: String
Mandatory: Yes Mandatory: Yes
Key: case-sensitive Key: case-sensitive
Description: Flag indicating whether or not case-sensitive Description: Flag indicating whether or not case-sensitive
matching should be used. matching should be used.
Type: Boolean Type: Boolean
Mandatory: No, default is case-insensitive match. Mandatory: No, default is case-insensitive match.
Key: match-query-string Key: match-query-string
Description: Flag indicating whether or not the query string Description: Flag indicating whether or not the query string
should be included in the pattern match. should be included in the pattern match.
Type: Boolean Type: Boolean
Mandatory: No, default is not to include query. Mandatory: No, default is not to include query.
Example of case-sensitive prefix match against Example of case-sensitive prefix match against
"http://www.example.com/trailers/": "http://www.example.com/trailers/":
{ {
"pattern": "http://www.example.com/trailers/*", "pattern": "http://www.example.com/trailers/*",
"case-sensitive": true "case-sensitive": true
} }
6.1.4. ErrorDesc 6.1.4. ErrorDesc
ErrorDesc shall be encoded as a JSON object with the following keys: ErrorDesc is encoded as a JSON object with the following keys:
Key: error Key: error
Type: ErrorCode Type: ErrorCode
Mandatory: Yes Mandatory: Yes
Keys: metadata.urls, content.urls Keys: metadata.urls, content.urls
Type: Array of strings Type: Array of strings
Mandatory: At least one of metadata.* or content.* must be
Mandatory: At least one of metadata.* or content.* MUST be
present. present.
Keys: metadata.patterns, content.patterns Keys: metadata.patterns, content.patterns
Type: Array of PatternMatch Type: Array of PatternMatch
Mandatory: At least one of metadata.* or content.* must be
Mandatory: At least one of metadata.* or content.* MUST be
present. present.
Key: description Key: description
Type: String Type: String
Mandatory: No. Mandatory: No.
6.1.5. ErrorCode 6.1.5. ErrorCode
One of the strings "EMETA", "ECONTENT", "EPERM", "EREJECT" or "ECDN". One of the strings "EMETA", "ECONTENT", "EPERM", "EREJECT" or "ECDN".
6.1.6. Relationship
The key "_links" in a dictionary object may be used to define
ralationships to other resources. Keys of the "_links" dictionary
are link relation types, the value for each relation type can either
be a Link Object or an array of Link Objects.
The relation type "self" SHOULD be included, with the target being
the containing resource.
6.1.7. Link Object
A Link Object is a JSON dictionary containing the following keys:
o "href" - With a value containing the URI of the of the addressable
object being referenced. The "href" must be specified.
o "type" - The MIME Media Type of the referenced object. It is
optional to specify "type". See Section 6.2 for the MIME Media
Types of objects specified in this document.
6.2. MIME Media Types 6.2. MIME Media Types
Table 1 lists the MIME Media Type for the trigger request, and each Table 1 lists the MIME Media Type for the trigger request, and each
trigger object (resource) that is retrievable through the CI/T trigger object (resource) that is retrievable through the CI/T
interface. interface.
+-------------------+--------------------------------------------+ +-------------------+--------------------------------------------+
| Data Object | MIME Media Type | | Data Object | MIME Media Type |
+-------------------+--------------------------------------------+ +-------------------+--------------------------------------------+
| TriggerRequest | application/cdni.ci.TriggerRequest+json | | TriggerRequest | application/cdni.ci.TriggerRequest+json |
skipping to change at page 20, line 44 skipping to change at page 22, line 35
7. Examples 7. Examples
The following sections provide examples of different CI/T objects The following sections provide examples of different CI/T objects
encoded as JSON. encoded as JSON.
No authentication is shown in the following illustrative examples, it No authentication is shown in the following illustrative examples, it
is anticipated that authentication mechanisms will be aligned with is anticipated that authentication mechanisms will be aligned with
other CDNI Interfaces as and when those mechanisms are defined. other CDNI Interfaces as and when those mechanisms are defined.
Discovery of the triggers interface is out of scope of this document. Discovery of the triggers interface is out of scope of this document.
In an implementation, all URLs are under control of dCDN and the uCDN In an implementation, all URLs are under the control of the dCDN.
must not attempt to ascribe any meaning to individual elements of the The uCDN MUST NOT attempt to ascribe any meaning to individual
path. In examples in this section, the following URLs are used as elements of the path. In examples in this section, the following
the location of the collections of triggers: URLs are used as the location of the collections of triggers:
o Collection of all Triggers belonging to one uCDN: o Collection of all Triggers belonging to one uCDN:
http://dcdn.example.com/triggers http://dcdn.example.com/triggers
o Filtered collections: o Filtered collections:
Pending: http://dcdn.example.com/triggers/pending Pending: http://dcdn.example.com/triggers/pending
Active: http://dcdn.example.com/triggers/active Active: http://dcdn.example.com/triggers/active
Complete: http://dcdn.example.com/triggers/complete Complete: http://dcdn.example.com/triggers/complete
Failed: http://dcdn.example.com/triggers/failed Failed: http://dcdn.example.com/triggers/failed
7.1. Creating Triggers 7.1. Creating Triggers
Examples of uCDN triggering activity in dCDN: Examples of uCDN triggering activity in dCDN:
7.1.1. Preposition 7.1.1. Preposition
An example of a preposition request, a POST to the "AllTriggers" An example of a preposition request, a POST to the "AllTriggers"
collection. collection.
skipping to change at page 21, line 49 skipping to change at page 23, line 43
"http://www.example.com/a/b/c/2", "http://www.example.com/a/b/c/2",
"http://www.example.com/a/b/c/3", "http://www.example.com/a/b/c/3",
"http://www.example.com/a/b/c/4" "http://www.example.com/a/b/c/4"
] ]
} }
} }
RESPONSE: RESPONSE:
HTTP/1.1 201 Created HTTP/1.1 201 Created
Date: Mon, 11 Nov 2013 03:28:27 GMT Date: Wed, 02 Jul 2014 18:57:19 GMT
Content-Length: 472 Content-Length: 472
Content-Type: application/cdni.ci.TriggerStatus+json Content-Type: application/cdni.ci.TriggerStatus+json
Location: http://dcdn.example.com/triggers/0 Location: http://dcdn.example.com/triggers/0
Server: example-server/0.1 Server: example-server/0.1
{ {
"ctime": 1384140507, "ctime": 1404327439,
"etime": 1384140515, "etime": 1404327447,
"mtime": 1384140507, "mtime": 1404327439,
"status": "pending", "status": "pending",
"trigger": { "trigger": {
"content.urls": [ "content.urls": [
"http://www.example.com/a/b/c/1", "http://www.example.com/a/b/c/1",
"http://www.example.com/a/b/c/2", "http://www.example.com/a/b/c/2",
"http://www.example.com/a/b/c/3", "http://www.example.com/a/b/c/3",
"http://www.example.com/a/b/c/4" "http://www.example.com/a/b/c/4"
], ],
"metadata.urls": [ "metadata.urls": [
"http://metadata.example.com/a/b/c" "http://metadata.example.com/a/b/c"
], ],
"type": "preposition" "type": "preposition"
} }
} }
7.1.2. Invalidate 7.1.2. Invalidate
An example of an invalidate request, another POST to the An example of an invalidate request, another POST to the
"AllTriggers" collection. This instructs dCDN to re-validate the "AllTriggers" collection. This instructs the dCDN to re-validate the
content at "http://www.example.com/a/index.html", as well as any content at "http://www.example.com/a/index.html", as well as any
metadata and content whose URLs are prefixed by metadata and content whose URLs are prefixed by
"http://metadata.example.com/a/b/" and "http://www.example.com/a/b/" "http://metadata.example.com/a/b/" and "http://www.example.com/a/b/"
respectively, using case-insensitive matching. respectively, using case-insensitive matching.
REQUEST: REQUEST:
POST /triggers HTTP/1.1 POST /triggers HTTP/1.1
User-Agent: example-user-agent/0.1 User-Agent: example-user-agent/0.1
Host: dcdn.example.com Host: dcdn.example.com
Accept: */* Accept: */*
Content-Type: application/cdni.ci.TriggerRequest+json Content-Type: application/cdni.ci.TriggerRequest+json
Content-Length: 352 Content-Length: 352
{ {
skipping to change at page 23, line 9 skipping to change at page 25, line 4
{ "pattern" : "http://metadata.example.com/a/b/*" } { "pattern" : "http://metadata.example.com/a/b/*" }
], ],
"content.urls" : [ "http://www.example.com/a/index.html" ], "content.urls" : [ "http://www.example.com/a/index.html" ],
"content.patterns" : [ "content.patterns" : [
{ "pattern" : "http://www.example.com/a/b/*", { "pattern" : "http://www.example.com/a/b/*",
"case-sensitive" : true "case-sensitive" : true
} }
] ]
} }
} }
RESPONSE: RESPONSE:
HTTP/1.1 201 Created HTTP/1.1 201 Created
Date: Mon, 11 Nov 2013 03:28:28 GMT Date: Wed, 02 Jul 2014 18:57:20 GMT
Content-Length: 551 Content-Length: 551
Content-Type: application/cdni.ci.TriggerStatus+json Content-Type: application/cdni.ci.TriggerStatus+json
Location: http://dcdn.example.com/triggers/1 Location: http://dcdn.example.com/triggers/1
Server: example-server/0.1 Server: example-server/0.1
{ {
"ctime": 1384140508, "ctime": 1404327440,
"etime": 1384140516, "etime": 1404327448,
"mtime": 1384140508, "mtime": 1404327440,
"status": "pending", "status": "pending",
"trigger": { "trigger": {
"content.patterns": [ "content.patterns": [
{ {
"case-sensitive": true, "case-sensitive": true,
"pattern": "http://www.example.com/a/b/*" "pattern": "http://www.example.com/a/b/*"
} }
], ],
"content.urls": [ "content.urls": [
"http://www.example.com/a/index.html" "http://www.example.com/a/index.html"
skipping to change at page 23, line 46 skipping to change at page 25, line 42
{ {
"pattern": "http://metadata.example.com/a/b/*" "pattern": "http://metadata.example.com/a/b/*"
} }
], ],
"type": "invalidate" "type": "invalidate"
} }
} }
7.2. Examining Trigger Status 7.2. Examining Trigger Status
Once triggers have been created, uCDN can check their status as shown Once triggers have been created, the uCDN can check their status as
in these examples. shown in these examples.
7.2.1. Collection of All Triggers 7.2.1. Collection of All Triggers
The uCDN can fetch the set of all the triggers it has created and The uCDN can fetch the set of all the triggers it has created and
which have not yet been deleted or removed as expired. After which have not yet been deleted or removed as expired. After
creation of the "preposition" and "invalidate" triggers shown above, creation of the "preposition" and "invalidate" triggers shown above,
this collection might look as follows: this collection might look as follows:
REQUEST: REQUEST:
GET /triggers HTTP/1.1 GET /triggers HTTP/1.1
User-Agent: example-user-agent/0.1 User-Agent: example-user-agent/0.1
Host: dcdn.example.com Host: dcdn.example.com
Accept: */* Accept: */*
RESPONSE: RESPONSE:
HTTP/1.1 200 OK HTTP/1.1 200 OK
skipping to change at page 24, line 21 skipping to change at page 26, line 15
REQUEST: REQUEST:
GET /triggers HTTP/1.1 GET /triggers HTTP/1.1
User-Agent: example-user-agent/0.1 User-Agent: example-user-agent/0.1
Host: dcdn.example.com Host: dcdn.example.com
Accept: */* Accept: */*
RESPONSE: RESPONSE:
HTTP/1.1 200 OK HTTP/1.1 200 OK
Content-Length: 489 Content-Length: 153
Expires: Mon, 11 Nov 2013 03:29:28 GMT Expires: Wed, 02 Jul 2014 18:58:20 GMT
Server: example-server/0.1 Server: example-server/0.1
ETag: "8477575226503289820" Etag: "9179988753593038498"
Cache-Control: max-age=60 Cache-Control: max-age=60
Date: Mon, 11 Nov 2013 03:28:28 GMT Date: Wed, 02 Jul 2014 18:57:20 GMT
Content-Type: application/cdni.ci.TriggerCollection+json Content-Type: application/cdni.ci.TriggerCollection+json
{ {
"_links": { "staleresourcetime": 86400,
"Trigger": [ "triggers": [
{ "http://dcdn.example.com/triggers/0",
"href": "http://dcdn.example.com/triggers/0", "http://dcdn.example.com/triggers/1"
"type": "application/cdni.ci.TriggerStatus+json" ]
},
{
"href": "http://dcdn.example.com/triggers/1",
"type": "application/cdni.ci.TriggerStatus+json"
}
],
"self": {
"href": "http://dcdn.example.com/triggers"
}
},
"staleresourcetime": 86400
} }
7.2.2. Filtered Collections of Triggers 7.2.2. Filtered Collections of Triggers
The filtered collections are also available to uCDN. Before dCDN The filtered collections are also available to uCDN. Before the dCDN
starts processing the two triggers shown above, both will appear in starts processing the two triggers shown above, both will appear in
the collection of Pending Triggers, for example: the collection of Pending Triggers, for example:
REQUEST:
RREQUEST:
GET /triggers/pending HTTP/1.1 GET /triggers/pending HTTP/1.1
User-Agent: example-user-agent/0.1 User-Agent: example-user-agent/0.1
Host: dcdn.example.com Host: dcdn.example.com
Accept: */* Accept: */*
RESPONSE: RESPONSE:
HTTP/1.1 200 OK HTTP/1.1 200 OK
Content-Length: 497 Content-Length: 153
Expires: Mon, 11 Nov 2013 03:29:28 GMT Expires: Wed, 02 Jul 2014 18:58:20 GMT
Server: example-server/0.1 Server: example-server/0.1
ETag: "-4197252672546627852" Etag: "5012053611544832286"
Cache-Control: max-age=60 Cache-Control: max-age=60
Date: Mon, 11 Nov 2013 03:28:28 GMT Date: Wed, 02 Jul 2014 18:57:20 GMT
Content-Type: application/cdni.ci.TriggerCollection+json Content-Type: application/cdni.ci.TriggerCollection+json
{ {
"_links": { "staleresourcetime": 86400,
"Trigger": [ "triggers": [
{ "http://dcdn.example.com/triggers/0",
"href": "http://dcdn.example.com/triggers/0", "http://dcdn.example.com/triggers/1"
"type": "application/cdni.ci.TriggerStatus+json" ]
},
{
"href": "http://dcdn.example.com/triggers/1",
"type": "application/cdni.ci.TriggerStatus+json"
}
],
"self": {
"href": "http://dcdn.example.com/triggers/pending"
}
},
"staleresourcetime": 86400
} }
At this point, if no other triggers had been created, the other At this point, if no other triggers had been created, the other
filtered views of the triggers would be empty. For example: filtered views of the triggers would be empty. For example:
REQUEST: REQUEST:
GET /triggers/complete HTTP/1.1 GET /triggers/complete HTTP/1.1
User-Agent: example-user-agent/0.1 User-Agent: example-user-agent/0.1
Host: dcdn.example.com Host: dcdn.example.com
Accept: */* Accept: */*
RESPONSE: RESPONSE:
HTTP/1.1 200 OK HTTP/1.1 200 OK
Content-Length: 151 Content-Length: 56
Expires: Mon, 11 Nov 2013 03:29:28 GMT Expires: Wed, 02 Jul 2014 18:58:20 GMT
Server: example-server/0.1 Server: example-server/0.1
ETag: "-3759884165278932652" Etag: "2986340333785000363"
Cache-Control: max-age=60 Cache-Control: max-age=60
Date: Mon, 11 Nov 2013 03:28:28 GMT Date: Wed, 02 Jul 2014 18:57:20 GMT
Content-Type: application/cdni.ci.TriggerCollection+json Content-Type: application/cdni.ci.TriggerCollection+json
{ {
"_links": { "staleresourcetime": 86400,
"self": { "triggers": []
"href": "http://dcdn.example.com/triggers/complete"
}
},
"staleresourcetime": 86400
} }
7.2.3. Trigger Status Resources 7.2.3. Trigger Status Resources
The Trigger Status Resources can also be examined for detail about The Trigger Status Resources can also be examined for detail about
individual triggers. For example, for the "preposition" and individual triggers. For example, for the "preposition" and
"invalidate" triggers from previous examples: "invalidate" triggers from previous examples:
REQUEST: REQUEST:
GET /triggers/0 HTTP/1.1 GET /triggers/0 HTTP/1.1
User-Agent: example-user-agent/0.1 User-Agent: example-user-agent/0.1
Host: dcdn.example.com Host: dcdn.example.com
Accept: */* Accept: */*
RESPONSE: RESPONSE:
HTTP/1.1 200 OK HTTP/1.1 200 OK
Content-Length: 472 Content-Length: 472
Expires: Mon, 11 Nov 2013 03:29:28 GMT Expires: Wed, 02 Jul 2014 18:58:20 GMT
Server: example-server/0.1 Server: example-server/0.1
ETag: "4936922742974586536" Etag: "-3651695664007658154"
Cache-Control: max-age=60 Cache-Control: max-age=60
Date: Mon, 11 Nov 2013 03:28:28 GMT Date: Wed, 02 Jul 2014 18:57:20 GMT
Content-Type: application/cdni.ci.TriggerStatus+json Content-Type: application/cdni.ci.TriggerStatus+json
{ {
"ctime": 1384140507, "ctime": 1404327439,
"etime": 1384140515, "etime": 1404327447,
"mtime": 1384140507, "mtime": 1404327439,
"status": "pending", "status": "pending",
"trigger": { "trigger": {
"content.urls": [ "content.urls": [
"http://www.example.com/a/b/c/1", "http://www.example.com/a/b/c/1",
"http://www.example.com/a/b/c/2", "http://www.example.com/a/b/c/2",
"http://www.example.com/a/b/c/3", "http://www.example.com/a/b/c/3",
"http://www.example.com/a/b/c/4" "http://www.example.com/a/b/c/4"
], ],
"metadata.urls": [ "metadata.urls": [
"http://metadata.example.com/a/b/c" "http://metadata.example.com/a/b/c"
skipping to change at page 28, line 16 skipping to change at page 30, line 16
GET /triggers/1 HTTP/1.1 GET /triggers/1 HTTP/1.1
User-Agent: example-user-agent/0.1 User-Agent: example-user-agent/0.1
Host: dcdn.example.com Host: dcdn.example.com
Accept: */* Accept: */*
RESPONSE: RESPONSE:
HTTP/1.1 200 OK HTTP/1.1 200 OK
Content-Length: 551 Content-Length: 551
Expires: Mon, 11 Nov 2013 03:29:28 GMT Expires: Wed, 02 Jul 2014 18:58:20 GMT
Server: example-server/0.1 Server: example-server/0.1
ETag: "-4441420523993853535" Etag: "-7664987687828084413"
Cache-Control: max-age=60 Cache-Control: max-age=60
Date: Mon, 11 Nov 2013 03:28:28 GMT Date: Wed, 02 Jul 2014 18:57:20 GMT
Content-Type: application/cdni.ci.TriggerStatus+json Content-Type: application/cdni.ci.TriggerStatus+json
{ {
"ctime": 1384140508, "ctime": 1404327440,
"etime": 1384140516, "etime": 1404327448,
"mtime": 1384140508, "mtime": 1404327440,
"status": "pending", "status": "pending",
"trigger": { "trigger": {
"content.patterns": [ "content.patterns": [
{ {
"case-sensitive": true, "case-sensitive": true,
"pattern": "http://www.example.com/a/b/*" "pattern": "http://www.example.com/a/b/*"
} }
], ],
"content.urls": [ "content.urls": [
"http://www.example.com/a/index.html" "http://www.example.com/a/index.html"
skipping to change at page 29, line 11 skipping to change at page 31, line 11
The uCDN may use the Entity Tags of collections or resources when The uCDN may use the Entity Tags of collections or resources when
polling for change in status, as shown in the following examples: polling for change in status, as shown in the following examples:
REQUEST: REQUEST:
GET /triggers/pending HTTP/1.1 GET /triggers/pending HTTP/1.1
User-Agent: example-user-agent/0.1 User-Agent: example-user-agent/0.1
Host: dcdn.example.com Host: dcdn.example.com
Accept: */* Accept: */*
If-None-Match: "-4197252672546627852" If-None-Match: "5012053611544832286"
RESPONSE: RESPONSE:
HTTP/1.1 304 Not Modified HTTP/1.1 304 Not Modified
Content-Length: 0 Content-Length: 0
Expires: Mon, 11 Nov 2013 03:29:28 GMT Expires: Wed, 02 Jul 2014 18:58:20 GMT
Server: example-server/0.1 Server: example-server/0.1
ETag: "-4197252672546627852" Etag: "5012053611544832286"
Cache-Control: max-age=60 Cache-Control: max-age=60
Date: Mon, 11 Nov 2013 03:28:28 GMT Date: Wed, 02 Jul 2014 18:57:20 GMT
Content-Type: application/cdni.ci.TriggerCollection+json Content-Type: application/cdni.ci.TriggerCollection+json
REQUEST: REQUEST:
GET /triggers/0 HTTP/1.1 GET /triggers/0 HTTP/1.1
User-Agent: example-user-agent/0.1 User-Agent: example-user-agent/0.1
Host: dcdn.example.com Host: dcdn.example.com
Accept: */* Accept: */*
If-None-Match: "4936922742974586536" If-None-Match: "-3651695664007658154"
RESPONSE: RESPONSE:
HTTP/1.1 304 Not Modified HTTP/1.1 304 Not Modified
Content-Length: 0 Content-Length: 0
Expires: Mon, 11 Nov 2013 03:29:28 GMT Expires: Wed, 02 Jul 2014 18:58:20 GMT
Server: example-server/0.1 Server: example-server/0.1
ETag: "4936922742974586536" Etag: "-3651695664007658154"
Cache-Control: max-age=60 Cache-Control: max-age=60
Date: Mon, 11 Nov 2013 03:28:28 GMT Date: Wed, 02 Jul 2014 18:57:20 GMT
Content-Type: application/cdni.ci.TriggerStatus+json Content-Type: application/cdni.ci.TriggerStatus+json
When the triggered activity is complete, the contents of the filtered When the triggered activity is complete, the contents of the filtered
collections will be updated, along with their Entity Tags. For collections will be updated, along with their Entity Tags. For
example, when the two example triggers are complete, the collections example, when the two example triggers are complete, the collections
of pending and complete triggers may look like: of pending and complete triggers may look like:
REQUEST: REQUEST:
GET /triggers/pending HTTP/1.1 GET /triggers/pending HTTP/1.1
User-Agent: example-user-agent/0.1 User-Agent: example-user-agent/0.1
Host: dcdn.example.com Host: dcdn.example.com
Accept: */* Accept: */*
RESPONSE: RESPONSE:
HTTP/1.1 200 OK HTTP/1.1 200 OK
Content-Length: 150 Content-Length: 56
Expires: Mon, 11 Nov 2013 03:29:39 GMT Expires: Wed, 02 Jul 2014 18:58:24 GMT
Server: example-server/0.1 Server: example-server/0.1
ETag: "-8587750650096537234" Etag: "-4471185573414616962"
Cache-Control: max-age=60 Cache-Control: max-age=60
Date: Mon, 11 Nov 2013 03:28:39 GMT Date: Wed, 02 Jul 2014 18:57:24 GMT
Content-Type: application/cdni.ci.TriggerCollection+json Content-Type: application/cdni.ci.TriggerCollection+json
{ {
"_links": { "staleresourcetime": 86400,
"self": { "triggers": []
"href": "http://dcdn.example.com/triggers/pending"
}
},
"staleresourcetime": 86400
} }
REQUEST: REQUEST:
GET /triggers/complete HTTP/1.1 GET /triggers/complete HTTP/1.1
User-Agent: example-user-agent/0.1 User-Agent: example-user-agent/0.1
Host: dcdn.example.com Host: dcdn.example.com
Accept: */* Accept: */*
RESPONSE: RESPONSE:
HTTP/1.1 200 OK HTTP/1.1 200 OK
Content-Length: 498 Content-Length: 153
Expires: Mon, 11 Nov 2013 03:29:39 GMT Expires: Wed, 02 Jul 2014 18:58:31 GMT
Server: example-server/0.1 Server: example-server/0.1
ETag: "2680225545549998872" Etag: "-1508172875796647067"
Cache-Control: max-age=60 Cache-Control: max-age=60
Date: Mon, 11 Nov 2013 03:28:39 GMT Date: Wed, 02 Jul 2014 18:57:31 GMT
Content-Type: application/cdni.ci.TriggerCollection+json Content-Type: application/cdni.ci.TriggerCollection+json
{ {
"_links": { "staleresourcetime": 86400,
"Trigger": [ "triggers": [
{ "http://dcdn.example.com/triggers/0",
"href": "http://dcdn.example.com/triggers/0", "http://dcdn.example.com/triggers/1"
"type": "application/cdni.ci.TriggerStatus+json" ]
},
{
"href": "http://dcdn.example.com/triggers/1",
"type": "application/cdni.ci.TriggerStatus+json"
}
],
"self": {
"href": "http://dcdn.example.com/triggers/complete"
}
},
"staleresourcetime": 86400
} }
7.2.5. Cancelling or Removing a Trigger 7.2.5. Cancelling or Removing a Trigger
To request dCDN to cancel a Trigger, uCDN may delete the Trigger To request the dCDN to cancel a Trigger, the uCDN may delete the
Resource. It may also delete completed and failed triggers to reduce Trigger Resource. It may also delete completed and failed triggers
the size of the collections. For example, to remove the to reduce the size of the collections. For example, to remove the
"preposition" request from earlier examples: "preposition" request from earlier examples:
REQUEST: REQUEST:
DELETE /triggers/0 HTTP/1.1 DELETE /triggers/0 HTTP/1.1
User-Agent: example-user-agent/0.1 User-Agent: example-user-agent/0.1
Host: dcdn.example.com Host: dcdn.example.com
Accept: */* Accept: */*
RESPONSE: RESPONSE:
HTTP/1.1 204 No Content HTTP/1.1 204 No Content
Date: Mon, 11 Nov 2013 03:28:39 GMT Date: Wed, 02 Jul 2014 18:57:31 GMT
Content-Length: 0 Content-Length: 0
Content-Type: text/html; charset=UTF-8 Content-Type: text/html; charset=UTF-8
Server: example-server/0.1 Server: example-server/0.1
This would, for example, cause the collection of completed triggers This would, for example, cause the collection of completed triggers
shown in the example above to be updated to: shown in the example above to be updated to:
REQUEST: REQUEST:
GET /triggers/complete HTTP/1.1 GET /triggers/complete HTTP/1.1
User-Agent: example-user-agent/0.1 User-Agent: example-user-agent/0.1
Host: dcdn.example.com Host: dcdn.example.com
Accept: */* Accept: */*
RESPONSE: RESPONSE:
HTTP/1.1 200 OK HTTP/1.1 200 OK
Content-Length: 304 Content-Length: 106
Expires: Mon, 11 Nov 2013 03:29:39 GMT Expires: Wed, 02 Jul 2014 18:58:31 GMT
Server: example-server/0.1 Server: example-server/0.1
ETag: "535044172999094664" Etag: "-1842390246836476263"
Cache-Control: max-age=60 Cache-Control: max-age=60
Date: Mon, 11 Nov 2013 03:28:39 GMT Date: Wed, 02 Jul 2014 18:57:31 GMT
Content-Type: application/cdni.ci.TriggerCollection+json Content-Type: application/cdni.ci.TriggerCollection+json
{ {
"_links": { "staleresourcetime": 86400,
"Trigger": { "triggers": [
"href": "http://dcdn.example.com/triggers/1", "http://dcdn.example.com/triggers/1"
"type": "application/cdni.ci.TriggerStatus+json" ]
},
"self": {
"href": "http://dcdn.example.com/triggers/complete"
}
},
"staleresourcetime": 86400
} }
7.2.6. Error Reporting 7.2.6. Error Reporting
In this example uCDN has requested prepositioning of In this example the uCDN has requested prepositioning of
"http://newsite.example.com/index.html", but dCDN was unable to "http://newsite.example.com/index.html", but the dCDN was unable to
locate metadata for that site: locate metadata for that site:
REQUEST: REQUEST:
GET /triggers/2 HTTP/1.1 GET /triggers/2 HTTP/1.1
User-Agent: example-user-agent/0.1 User-Agent: example-user-agent/0.1
Host: dcdn.example.com Host: dcdn.example.com
Accept: */* Accept: */*
RESPONSE: RESPONSE:
HTTP/1.1 200 OK HTTP/1.1 200 OK
Content-Length: 505 Content-Length: 505
Expires: Mon, 11 Nov 2013 03:29:43 GMT Expires: Wed, 02 Jul 2014 19:16:48 GMT
Server: example-server/0.1 Server: example-server/0.1
ETag: "3841389629056746224" Etag: "-6310233270471598826"
Cache-Control: max-age=60 Cache-Control: max-age=60
Date: Mon, 11 Nov 2013 03:28:43 GMT Date: Wed, 02 Jul 2014 19:15:48 GMT
Content-Type: application/cdni.ci.TriggerStatus+json Content-Type: application/cdni.ci.TriggerStatus+json
{ {
"ctime": 1384140519, "ctime": 1404328544,
"errors": [ "errors": [
{ {
"content.urls": [ "content.urls": [
"http://newsite.example.com/index.html" "http://newsite.example.com/index.html"
], ],
"description": "description":
"No HostIndex entry found for newsite.example.com", "No HostIndex entry found for newsite.example.com",
"error": "EMETA" "error": "EMETA"
} }
], ],
"etime": 1384140527, "etime": 1404328552,
"mtime": 1384140523, "mtime": 1404328548,
"status": "active", "status": "active",
"trigger": { "trigger": {
"content.urls": [ "content.urls": [
"http://newsite.example.com/index.html" "http://newsite.example.com/index.html"
], ],
"type": "preposition" "type": "preposition"
} }
} }
8. IANA Considerations 8. IANA Considerations
skipping to change at page 35, line 4 skipping to change at page 36, line 6
"status": "active", "status": "active",
"trigger": { "trigger": {
"content.urls": [ "content.urls": [
"http://newsite.example.com/index.html" "http://newsite.example.com/index.html"
], ],
"type": "preposition" "type": "preposition"
} }
} }
8. IANA Considerations 8. IANA Considerations
8.1. CI/T MIME Media Types 8.1. CI/T MIME Media Types
The IANA is requested to allocate the following MIME Media Types in The IANA is requested to allocate the following MIME Media Types in
the MIME Media Types registry: the MIME Media Types registry:
o application/cdni.ci.TriggerRequest o application/cdni.ci.TriggerRequest
o application/cdni.ci.TriggerStatus o application/cdni.ci.TriggerStatus
o application/cdni.ci.TriggerCollection o application/cdni.ci.TriggerCollection
Use of these types is specified in Section 6.2 of the present Use of these types is specified in Section 6.2 of the present
document. document.
9. Security Considerations 9. Security Considerations
The dCDN must ensure that each uCDN only has access to its own 9.1. Authentication, Confidentiality, Integrity Protection
Trigger Status Resources.
It is anticipated that a common authentication mechanism will be used A CI/T dCDN server implementation MUST support TLS transport for HTTP
by this and other CDNI Interconnect interfaces, the mechanism must (https) as per [RFC2818]. The use of TLS for transport of the CI/T
exist but is not identified in this document. interface allows the dCDN and the uCDN to authenticate each other (to
ensure they are receiving trigger requests from, or reporting status
to, an authenticated CDN).
The dCDN must ensure that activity triggered by uCDN only affects HTTP requests that attempt to access or operate on CI/T data
metadata or content originating from that uCDN. belonging to another CDN MUST be rejected using either HTTP "403
Forbidden" or "404 Not Found". (Note that in a "diamond"
configuration, where one uCDN's content can be acquired via more than
one directly-connected uCDN, it may not be possible for the dCDN to
determine from which uCDN it acquired content. In this case, it MUST
allow each upstream that may have been responsible for acquisition of
that content to act upon it using trigger requests.)
Trigger creation requests that attempt to operate on metadata or
content not acquired from the uCDN making the request MUST be
rejected. The rejection can either be signalled to dCDN using HTTP
"403 Forbidden" or "404 Not Found", or a Trigger Status Resource can
be created with an ErrorDesc value of EPERM for any affected URLs.
In an environment where any such protection is required, TLS SHOULD
be used for transport of the CI/T requests and responses, unless
alternate methods are used for ensuring that only authorised clients
are able to access their own data (such as setting up an IPsec tunnel
between the two CDNs, or using a physically secured internal network
between two CDNs that are owned by the same corporate entity). Both
parties of the transaction (the uCDN and the dCDN) SHOULD use mutual
authentication.
A CI/T implementation MUST support the
TLS_DHE_RSA_WITH_AES_128_GCM_SHA256 cipher suite ([RFC5288]). An
implementation of the CI/T Interface SHOULD prefer cipher suites
which support perfect forward secrecy over cipher suites that don't.
9.2. Denial of Service
This document does not define a specific mechanism to protect against
Denial of Service (DoS) attacks on the CI/T. However, CI/T endpoints
can be protected against DoS attacks through the use of TLS transport
and/or via mechanisms outside the scope of the CI/T interface, such
as firewalling or use of Virtual Private Networks (VPNs).
10. Acknowledgements 10. Acknowledgements
The structure of the Relationship and Link Objects specified in The authors thank Kevin Ma for his ongoing input.
Section 6 is based on Mike Kelly's work on JSON Hypertext Application
Language.
11. References 11. References
11.1. Normative References 11.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H.,
Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext
Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999.
[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform [RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
Resource Identifier (URI): Generic Syntax", STD 66, Resource Identifier (URI): Generic Syntax", STD 66, RFC
RFC 3986, January 2005. 3986, January 2005.
[RFC7159] Bray, T., "The JavaScript Object Notation (JSON) Data
Interchange Format", RFC 7159, March 2014.
[RFC7231] Fielding, R. and J. Reschke, "Hypertext Transfer Protocol
(HTTP/1.1): Semantics and Content", RFC 7231, June 2014.
[RFC7232] Fielding, R. and J. Reschke, "Hypertext Transfer Protocol
(HTTP/1.1): Conditional Requests", RFC 7232, June 2014.
11.2. Informative References 11.2. Informative References
[I-D.ietf-cdni-framework] [I-D.ietf-cdni-framework]
Peterson, L. and B. Davie, "Framework for CDN Peterson, L., Davie, B., and R. Brandenburg, "Framework
Interconnection", draft-ietf-cdni-framework-07 (work in for CDN Interconnection", draft-ietf-cdni-framework-14
progress), November 2013. (work in progress), June 2014.
[I-D.ietf-cdni-metadata] [I-D.ietf-cdni-metadata]
Niven-Jenkins, B., Murray, R., Watson, G., Caulfield, M., Niven-Jenkins, B., Murray, R., Watson, G., Caulfield, M.,
Leung, K., and K. Ma, "CDN Interconnect Metadata", Leung, K., and K. Ma, "CDN Interconnect Metadata", draft-
draft-ietf-cdni-metadata-03 (work in progress), ietf-cdni-metadata-06 (work in progress), February 2014.
October 2013.
[I-D.ietf-cdni-requirements] [I-D.ietf-cdni-requirements]
Leung, K. and Y. Lee, "Content Distribution Network Leung, K. and Y. Lee, "Content Distribution Network
Interconnection (CDNI) Requirements", Interconnection (CDNI) Requirements", draft-ietf-cdni-
draft-ietf-cdni-requirements-13 (work in progress), requirements-17 (work in progress), January 2014.
November 2013.
[RFC2818] Rescorla, E., "HTTP Over TLS", RFC 2818, May 2000.
[RFC4287] Nottingham, M., Ed. and R. Sayre, Ed., "The Atom [RFC4287] Nottingham, M., Ed. and R. Sayre, Ed., "The Atom
Syndication Format", RFC 4287, December 2005. Syndication Format", RFC 4287, December 2005.
[RFC5288] Salowey, J., Choudhury, A., and D. McGrew, "AES Galois
Counter Mode (GCM) Cipher Suites for TLS", RFC 5288,
August 2008.
[RFC6707] Niven-Jenkins, B., Le Faucheur, F., and N. Bitar, "Content [RFC6707] Niven-Jenkins, B., Le Faucheur, F., and N. Bitar, "Content
Distribution Network Interconnection (CDNI) Problem Distribution Network Interconnection (CDNI) Problem
Statement", RFC 6707, September 2012. Statement", RFC 6707, September 2012.
[XML-BASE] [XML-BASE]
Marsh, J., Ed. and R. Tobin, Ed., "XML Base (Second Marsh, J., Ed. and R. Tobin, Ed., "XML Base (Second
Edition) - http://www.w3.org/TR/xmlbase/", January 2009. Edition) - http://www.w3.org/TR/xmlbase/", January 2009.
Authors' Addresses Authors' Addresses
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