Activity Streams extensions
This page documents AS2 extensions: terms, contexts and namespaces that are often used in Activity Streams 2.0 documents that are not documented in Activity Streams 2.0 Core or Activity Vocabulary.
See also:
- https://www.w3.org/TR/activitystreams-core/#extensibility
- Activity Streams/Primer/Extensions
- Policy for including extensions in Activity Streams context
Extensions
Table fields:
- Name
- a common name for the extension and link to documentation
- Namespace
- the namespace prefix
- Context
- the context document URL
- Prefix
- the defined or commonly-used CURIE prefix
- Notes
- info about the extension
| Name | Namespace | Context | Prefix | Notes |
|---|---|---|---|---|
| ActivityPub | https://www.w3.org/ns/activitystreams# | N/A | as: | A widely-used social networking API and federation protocol, ActivityPub was standardized by the same working group as AS2, and its terms like inbox, likes and shares are included in the AS2 context document.
|
| alsoKnownAs | https://www.w3.org/ns/activitystreams# | N/A | as: | Decentralized Identifiers (DIDs) (DID Core v1.0 Terms) defines a alsoKnownAs term, for use as a property of DID documents. SocialCG allowed this term to be defined in the ActivityStreams 2.0 namespace, with the idea that the SocialCG and the DID community may further iterate on the definition[1]. The DIDs specification describes an example of using the alsoKnownAs property for assigning DIDs to web resources. |
| Security Vocabulary | https://w3id.org/security# | https://w3id.org/security/v1 | sec: | This vocabulary is widely used for implementing HTTP Signatures in ActivityPub. See https://swicg.github.io/activitypub-http-signature/ for details of terms and usage. |
| vCard | http://www.w3.org/2006/vcard/ns# | N/A | vcard: | Used for people, groups, organizations, contact information. Included as part of the AS2 context. |
| XMLSchema | http://www.w3.org/2001/XMLSchema# | N/A | xsd: | XML Schema vocabulary, used for basic types like numbers, strings, dates, and so forth. Included in the AS2 context document. |
| schema.org | http://schema.org/ | https://schema.org/docs/jsonldcontext.json | schema: | Extensive vocabulary covering many real-world types like people, locations, projects. |
| Linked Data Platform | http://www.w3.org/ns/ldp# | N/A | ldp: | Vocabulary for the a RESTful framework using Linked Data. Used for the inbox property for ActivityPub.
|
| ActivityPub Miscellaneous Terms | https://www.w3.org/ns/activitystreams# | https://purl.archive.org/socialweb/miscellany | as: | A group of widely-used miscellaneous terms added to the Activity Streams 2.0 namespace using the default vocabulary, including Hashtag, manuallyApprovesFollowers, movedTo, and sensitive.
|
| Mastodon extensions | http://joinmastodon.org/ns# | N/A | toot: | Extension terms defined by the Mastodon project for interoperability between Mastodon servers. No context document; Mastodon extension terms are defined in each @context property of Activity Streams documents served by the software.
|
| Relationship | http://purl.org/vocab/relationship | N/A | N/A | An extended vocabulary for social relationships, especially useful for the relationship property of the Relationship type. Representing Relationships Between Entities, an appendix of the Activity Vocabulary, uses the Relationships vocabulary for defining relationships.
|
| Misskey extensions | https://misskey-hub-net/ns# | N/A | misskey: | Extension terms defined by the Misskey project for interoperability between Misskey servers and derivatives. No context document; Misskey extension terms are defined in each @context property of Activity Streams documents served by the software. misskey:_quote_ is a property for quote-sharing.
|
| Object Integrity Proofs (FEP-8fcf) | https://w3id.org/security# | https://w3id.org/security/data-integrity/v1 | N/A | "Integrity proofs are sets of attributes that represent digital signatures and parameters required to verify them. These proofs can be added to any activity or object, allowing recipients to verify the identity of the actor and integrity of the data. That decouples authentication from the transport, and enables various protocol improvements such as activity relaying, embedded objects and client-side signing." |