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behavior.md

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title: ForgeFed Behavior

Abstract

This document provides instructions for using ActivityPub activities and properties to represent forge events, and describes the side-effects these activities should have.

Introduction

The ForgeFed behavior specification is a set of instructions for representing version control system and project management related transactions using ActivityPub activity objects, and it describes the side effects and expected results of sending and receiving these activities. The vocabulary for these activities includes standard ActivityPub terms, new terms defined by ForgeFed, and terms borrowed from other external vocabularies.

The ForgeFed vocabulary specification defines a dedicated vocabulary of forge-related terms, and the behavior specification uses these terms, along with terms that already exist in ActivityPub or elsewhere and can be reused for forge federation.

The ForgeFed modeling specification defines rules for representing forge related objects as ActivityPub JSON-LD objects, and these objects are used in the behavior specification, included in activities or mentioned in activities or modified due to activity side-effects.

Conformance

The key words MAY, MUST, MUST NOT, SHOULD, and SHOULD NOT are to be interpreted as described in RFC2119.

Objects

Kinds of Objects

Objects are the core concept around which both ActivityPub and ForgeFed are built. Examples of Objects are Note, Ticket, Image, Create, Push. Some objects are resources, which are objects that contain or represent information and user made or program made content, and some objects are helpers that exist as implementation detail aren't necessarily exposed to humans or are useful to humans. But everything is an Object, represented as compacted JSON-LD.

ForgeFed is an ActivityPub extension, and communication between ForgeFed implementations occurs using activity objects sent to actor inboxes and outboxes.

There are 4 kinds of objects in ForgeFed:

  1. Activities: These are objects that describe actions (actions that happened, or actions that are happening, or a request to perform an action), and their primary use is for S2S interaction between actors, by being sent to an actor's inbox, and C2S interaction between a person or a program and actor they control, by being sent to the actor's outbox. Activities can also appear or be linked inside other objects and activities and be listed in Collections.
  2. Actors: These are static persistent objects that have an inbox and can be directly interacted with by POSTing activities to it. Their primary use is to contain or represent information and output of user actions or program actions, and to manage access this information and to modification of it.
  3. Child objects: These are persistent objects which, like actors, contain or represent information and output of user actions or program actions, but they don't have their own inbox and aren't directly interacted with. A managed static object always has a parent object, which is an actor, and that actor's inbox is the way to interact with the child object. The parent actor manages access and modification of the child object.
  4. Global helper objects: These are objects that don't belong to any actor and don't need any interaction through activities. As such, they don't exactly fit into the actor model, but may be involved in implementation details and practical considerations.

Actors, children and globals are referred in ForgeFed as the static objects, while activities are the dynamic objects (the terms constant and variable are used for stating whether an object changes during its lifetime or not).

Static objects, in addition to being an actor or child or global, also have a resource/helper distinction:

  • Resource: Contains or represents information and user made or program made content, usually belongs to the domain model of version control systems and project management.
  • Helper: Used for running things behind the scenes, not exposed directly as user content, may be transient or auto generated, usually related to implementation detail and not to concepts of version control and project management.

Object Publishing and Hosting {#publishing}

In ForgeFed, actors host their child objects locally, i.e. the actor and the child object are hosted on the same instance. Actors may create remote objects by offering them to the relevant actor, which then may create the object on their side and assign it a URI.

The process begins with an Offer activity, in which:

  • object MUST be the object being offered for publishing, and that object MUST NOT have an id
  • target MUST indicate under which list/collection/context the sender would like the object to be published (it may also be the URI of the target actor itself)

Among the recipients listed in the Offer's recipient fields, exactly one recipient is the actor who's responsible for inspecting and possibly publishing the newly object, and possibly sending back an Accept or a Reject. We'll refer to this actor as the target actor. Specific object types described throughout this specification have a specific meaning for the target actor, which processing and inspection it is expected to do, and where it is expected to list the URI of the object once it publishes it.

The sender is essentially asking that the target actor hosts the object as a child object and assigns is a URI, allowing to observe and interact with the object. The target actor will be responsible for hosting and controlling the object, and the sender will just be mentioned as the author.

When an actor A receives the Offer activity, they can determine whether they're the target actor as follows: If the target is A or a child object of A, then A is the target actor. Otherwise, A isn't the target actor.

In the following example, Luke wants to open a ticket under Aviva's Game Of Life simulation app:

{
    "@context": [
        "https://www.w3.org/ns/activitystreams",
        "https://forgefed.org/ns"
    ],
    "id": "https://forge.example/luke/outbox/02Ljp",
    "type": "Offer",
    "actor": "https://forge.example/luke",
    "to": [
        "https://dev.example/aviva/game-of-life",
        "https://dev.example/aviva/game-of-life/team",
        "https://dev.example/aviva/game-of-life/followers"
    ],
    "object": {
        "type": "Ticket",
        "attributedTo": "https://forge.example/luke",
        "summary": "Test test test",
        "content": "<p>Just testing</p>",
        "mediaType": "text/html",
        "source": {
            "mediaType": "text/markdown; variant=Commonmark",
            "content": "Just testing"
        }
    },
    "target": "https://dev.example/aviva/game-of-life"
}

The target actor SHOULD send an Accept or a Reject activity to the Offer's author in response. If the target actor sends an Accept, it MUST host its own copy, assigning an id to the newly published object and adding it to the expected list specified by the Offer's target.

If the target actor sends a Reject, it MUST NOT add the object's id to that list. However if the target actor doesn't make any use of the object, it MAY choose not to send a Reject, e.g. to protect user privacy. The Accept or Reject may also be delayed, e.g. until review by a human user; that is implementation dependent, and implementations should not rely on an instant response.

In the Accept activity:

  • object MUST be the Offer activity or its id
  • result MUST be specified and be the id of the new child object now hosted by the target actor, which is extracted from the Offer's object

In the following example, Luke's ticket is opened automatically and Aviva's Game Of Life repository, which is an actor, automatically sends Luke an Accept activity:

{
    "@context": [
        "https://www.w3.org/ns/activitystreams",
        "https://forgefed.org/ns"
    ],
    "id": "https://dev.example/aviva/game-of-life/outbox/096al",
    "type": "Accept",
    "actor": "https://dev.example/aviva/game-of-life",
    "to": [
        "https://forge.example/luke",
        "https://dev.example/aviva/game-of-life/team",
        "https://dev.example/aviva/game-of-life/followers"
    ],
    "object": "https://forge.example/luke/outbox/02Ljp",
    "result": "https://dev.example/aviva/game-of-life/issues/113"
}

Client to Server Interactions

ForgeFed uses Activities for client to server interactions, as described by ActivityPub. A client will send objects (eg. a Ticket) wrapped in a Activity (eg. Create) to an actor's outbox, and in turn the server will take care of delivery.

Follow Activity

The Follow activity is used to subscribe to the activities of a Repository. The client MUST send a Follow activity to the Person's outbox. The server in turn delivers the message to the destination inbox.

Push Activity

The Push activity is used to notify followers when somebody has pushed changes to a Repository. The client MUST send a Push activity to the Repository's outbox. The server in turn delivers the message to the Repository followers.

Server to Server Interactions

Reporting Pushed Commits

The ForgeFed Push activity can be used for representing an action of pushing commits into a Repository. Two actors are involved in the process, the pusher (usually a person) and the repository, and they may be hosted on different instances. We therefore refer to 2 kinds of pushes:

  1. Local Push: The pusher and the repository are hosted on the same instance (that's the only case in centralized non-federated forges)
  2. Federated Push: The pusher and the repository are hosted on different instances (that's unique to federated forges)

At this time, the representation of Federated Push isn't provided yet. Below we discuss Local Push.

Upon a successful push, a ForgeFed implementation that publishes a Push activity MUST provide the type, actor, context and target properties as described in the modeling specification. If the Push activity's recipient fields list collections that belong to the repository, such as its followers and team, the repository MUST verify the authenticity and correctness of the Push activity's fields before it performs inbox forwarding (i.e. delivery to the members of those collections), and MUST NOT perform inbox delivery if the correctness check doesn't pass.

In a Local Push, if the Push activity is generated on the server, that obviates the need to perform correctness checking. Implementations MAY forbid clients from publishing Push activities (via the ActivityPub C2S API or any other mechanism), in order to guarantee the authenticity of Push activities.

See example in the modeling specification.

Opening a Ticket

The first step for opening a ticket is to determine to which actor to send the ticket. We'll refer to this actor as the ticket tracker. Given an object obj against which you'd like to open a ticket (e.g. some application's source code repository), look at the ticketsTrackedBy property of obj.

  • If ticketsTrackedBy isn't specified, then obj does't declare a way to open tickets via ForgeFed.
  • If ticketsTrackedBy is specified and is set to the id of obj itself, that means obj manages its own tickets, i.e. it is the ticket tracker to which you'll send the ticket.
  • If ticketsTrackedBy is specified and is set to some other object, look at the tracksTicketsFor property of that other object. If the id of obj is listed there under tracksTicketsFor, then that other object is the ticket tracker to which you'll send the ticket. Implementations SHOULD verify this bidirectional reference between the object and the tracker, and SHOULD NOT send a ticket if the bidirectional reference isn't found.

Now that we've determined the ticket tracker, i.e. the actor to whom we'll send the Ticket, the ticket may be opened using an Offer activity in which:

  • object is the ticket to be opened, it's a Ticket object with fields as described in the modeling specification. It MUST specify at least attributedTo, summary and content, and MUST NOT specify id. If it specifies a context, then it MUST be identical the Offer's target described below.
  • target is the ticket tracker to which the actor is offering the Ticket (e.g. a repository or project etc. under which the ticket will be opened if accepted). It MUST be either an actor or a child object. If it's a child object, the actor to whom the child object belongs MUST be listed as a recipient in the Offer's to field. If it's an actor, then that actor MUST be listed in the to field.

The target actor MAY then send back an Accept or Reject. The action that has been taken by the target actor is indicated to the ticket author as follows:

  • If a Reject was sent, it means the ticket hasn't been assigned an id URI by the tracker and isn't being tracked by the tracker
  • If an Accept was sent, it means the ticket is now tracked and hosted on the target's side

In the following example, Luke wants to open a ticket under Aviva's Game Of Life simulation app:

{
    "@context": [
        "https://www.w3.org/ns/activitystreams",
        "https://forgefed.org/ns"
    ],
    "id": "https://forge.example/luke/outbox/02Ljp",
    "type": "Offer",
    "actor": "https://forge.example/luke",
    "to": [
        "https://dev.example/aviva/game-of-life",
        "https://dev.example/aviva/game-of-life/team",
        "https://dev.example/aviva/game-of-life/followers"
    ],
    "object": {
        "type": "Ticket",
        "attributedTo": "https://forge.example/luke",
        "summary": "Test test test",
        "content": "<p>Just testing</p>",
        "mediaType": "text/html",
        "source": {
            "mediaType": "text/markdown; variant=Commonmark",
            "content": "Just testing"
        }
    },
    "target": "https://dev.example/aviva/game-of-life"
}

Luke's ticket is opened automatically and Aviva's Game Of Life repository, which is an actor, automatically sends Luke an Accept activity:

{
    "@context": [
        "https://www.w3.org/ns/activitystreams",
        "https://forgefed.org/ns"
    ],
    "id": "https://dev.example/aviva/game-of-life/outbox/096al",
    "type": "Accept",
    "actor": "https://dev.example/aviva/game-of-life",
    "to": [
        "https://forge.example/luke",
        "https://dev.example/aviva/game-of-life/team",
        "https://dev.example/aviva/game-of-life/followers"
    ],
    "object": "https://forge.example/luke/outbox/02Ljp",
    "result": "https://dev.example/aviva/game-of-life/issues/113"
}

Commenting

A comment on a ForgeFed resource object (such as tickets, merge requests) MUST be published as a Create activity, in which object is a Note with fields as described in the modeling specification.

In the following example, Luke replies to Aviva's comment under a merge request he submitted earlier against her Game Of Life simulation app repository:

{
    "@context": "https://www.w3.org/ns/activitystreams",
    "id": "https://forge.example/luke/outbox/rLaYo",
    "type": "Create",
    "actor": "https://forge.example/luke",
    "to": [
        "https://forge.example/luke/followers",
        "https://dev.example/aviva/game-of-life",
        "https://dev.example/aviva/game-of-life/followers",
        "https://dev.example/aviva/game-of-life/team",
        "https://dev.example/aviva/game-of-life/merge-requests/19/followers",
        "https://dev.example/aviva/game-of-life/merge-requests/19/team"
    ],
    "object": {
        "id": "https://forge.example/luke/comments/rD05r",
        "type": "Note",
        "attributedTo": "https://forge.example/luke",
        "to": [
            "https://forge.example/luke/followers",
            "https://dev.example/aviva/game-of-life",
            "https://dev.example/aviva/game-of-life/followers",
            "https://dev.example/aviva/game-of-life/team",
            "https://dev.example/aviva/game-of-life/merge-requests/19/followers",
            "https://dev.example/aviva/game-of-life/merge-requests/19/team"
        ],
        "context": "https://dev.example/aviva/game-of-life/merge-requests/19",
        "inReplyTo": "https://dev.example/aviva/comments/E9AGE",
        "mediaType": "text/html",
        "content": "<p>Thank you for the review! I'll submit a correction ASAP</p>",
        "source": {
            "mediaType": "text/markdown; variant=Commonmark",
            "content": "Thank you for the review! I'll submit a correction ASAP"
        },
        "published": "2019-11-06T20:49:05.604488Z"
    }
}

Granting access to shared resources

An actor that wishes to give other specific actors access to view or modify it (or a child object of it), SHOULD do so according to the following instructions.

Object capabilities using Grant activities {#s2s-grant-flow}

An Object Capability (or in short OCap or OCAP) is a token providing access to certain operations on a certain resource. An actor wishing to act on a resource provides the token to the resource, alongside the Activity they wish to perform. The resource verifies the token, and if and only if it finds the token valid, and access to the requested Activity is allowed by the token, then the resource allows the Activity to be performed.

The token provided by the actor to the resource, i.e. the OCAP, is the ID URI of a previously published Grant activity.

The fundamental steps for accessing shared resources using OCAPs are:

  1. The actor managing the resource (which may be the resource itself) sends a Grant activity to the actor to whom it wishes to grant access
  2. When the actor who received the access wishes to operate on the resource, it sends the activity to the actor managing the resource, along with the ID URI of the Grant sent in step 1
  3. The actor managing the resource verifies the access provided by the Grant whose ID URI is provided, and allows the activity to be performed only if the verification passes

Requirements for the Grant activity, i.e. step 1:

  • The Grant's context, i.e. the resource for which access is being given, MUST be the Grant's sender (i.e. its actor) or a child object of it
  • The Grant's object MUST be provided and specify a role determining which operations the recipient actor may perform on the resource; however this specification doesn't (yet) specify how to define or find such roles
  • The Grant's target MUST be provided, and specify exactly one actor to whom access is being given

Requirements for the activity (referred below as activity A) sent in step 3:

  • The OCAP, i.e. a URI of a Grant, is provided in activity A's capability property
  • If the actor managing the resource (from now on the resource actor) requires an OCAP for the action being requested by activity A, it MUST deny the activity unless all of the following holds:
    • The activity referred by the OCAP is a Grant activity
    • The Grant activity's actor is indeed the resource actor, and the resource actor can verify that it indeed published a Grant with the given URI
    • The Grant's context is the resource that activity A is requesting to access (to view and/or to modify)
    • The Grant's target is the sender (and actor) of activity A
    • The action being requested by activity A to perform on the resource is within what the resource actor permits for the role specified by the Grant's object

Identifying resources and their managing actors

Some shared resources are themselves actors, and some shared resources aren't actors, but they are child objects of actors. When some actor A wishes to access a resource R and perform a certain operation, it needs to determine which actor to contact in order to request that operation. Actor A then looks at resource R, and the following MUST hold:

  • Either the resource R isn't an actor (i.e. doesn't have an inbox) but does specify which actor manages it via the managedBy property ;
  • Or the resource R is an actor, i.e. it has an inbox (it doesn't have to specify managedBy, but if it does, then it MUST refer to itself)

Therefore any object that wishes to be specified as the context of a Grant MUST either be an actor or be managedBy an actor.

Initial Grant upon resource creation

When an actor A requests to create a new shared resource R, and the resource actor approves and creates it, then the resource actor SHOULD send a Grant to actor A, which provides actor A with access to resource R.

Typically, this Grant would provide actor A with what the resource actor considers full/admin access to resource R, which would typically include the ability to gives access to resource R to more actors (using an Invite activity, see below).

If such a Grant is sent by the resource actor upon the creation of resource R, then the Grant's fulfills property MUST be provided and specify the ID URI of the activity (published by actor A) that requested to create resource R (typically this would be an Offer activity, see Object Publishing and Hosting).

Offering access using Invite activities

When an actor A wishes to offer actor B access to resource R (where the resource actor who manages R is neither A nor B), then actor A SHOULD use an Invite activity, and the following steps:

  1. Actor A publishes and delivers an Invite, at least to actor B and to the resource actor of R, with a relevant capability (see Modeling specification for details on the properties to use)
  2. If actor B wishes to have the offered access, it publishes and delivers (at least to the resource actor of R) an Accept activity whose object specifies the Invite sent by actor A
  3. The resource actor of R receives the Invite and the Accept and: a. Verifies the Invite is authorized, as described above in Object capabilities using Grant activities b. Verifies that the Accept's object specifies the Invite and the Accept's actor is the Invite's object c. Publishes and delivers a Grant activity (see Modeling specification for more details on the properties) where: - object is the Invite's instrument - context is the Invite's target, which is resource R - target is the Invite's object, which is actor B - fulfills is the Invite

Actor B can now use the URI of that new Grant as the capability when it sends activities that access or manipulate resource R.

Requesting access using Join activities

When an actor A wishes to request access to resource R (where the resource actor who manages R isn't A), then actor A SHOULD use a Join activity, and the following steps. There are two options detailed below, depending on whether actor A has been previously given a Grant authorizing it to gain access to resource R without needing someone else to approve. For example, perhaps actor A already has some access to a resource collection to which R belongs, and that access allows A to freely Join R without needing to wait for human approval.

Option 1: Actor A already has a Grant allowing it to gain access to R without external approval:

  1. Actor A publishes and delivers a Join, at least to the resource actor of R, with the relevant capability it has (see Modeling specification for details on the properties to use)
  2. The resource actor of R receives the Join and: a. Verifies the Join is authorized, as described above in Object capabilities using Grant activities b. Publishes and delivers a Grant activity (see Modeling specification for more details on the properties) where: - object is the Join's instrument - context is the Join's object, which is resource R - target is the Join's actor, which is actor A - fulfills is the Join

Actor A can now use the URI of that new Grant as the capability when it sends activities that access or manipulate resource R.

Option 2: Actor A doesn't have (or chooses not to use) a Grant allowing it to gain access to R without external approval:

  1. Actor A publishes and delivers a Join, at least to the resource actor of R (see Modeling specification for details on the properties to use)
  2. If some actor B, that has previously received a Grant from the resource actor of R authorizing it to approve joins, sees the Join sent by actor A and decides to approve it, then actor B publishes and delivers (at least to the resource actor of R) an Accept activity where:
    • object specifies the Join sent by actor A
    • capability is the Grant mentioned above, authorizing to approve or deny Joins
  3. The resource actor of R receives the Join and the Accept and: a. Verifies the Accept is authorized, as described above in Object capabilities using Grant activities b. Verifies that the Accept's object specifies the Join c. Publishes and delivers a Grant activity (see Modeling specification for more details on the properties) where: - object is the Join's instrument - context is the Join's object, which is resource R - target is the Join's actor, which is actor A - fulfills is the Join

Actor A can now use the URI of that new Grant as the capability when it sends activities that access or manipulate resource R.

In step 2, actor B may choose to deny the request of actor A, by sending a Reject activity (at least to the resource actor of R) where:

  • object specifies the Join that actor A sent
  • capability is the Grant mentioned in step 2, authorizing actor B to approve or deny Joins

If the resource actor of R receives the Reject:

a. It MUST verify the Reject is authorized, as described above in Object capabilities using Grant activities b. it MUST verify that the Reject's object specifies the Join c. Consider this Join request canceled: If actor B, or some other actor C, tries again to Accept the Join, then:

  i. The *resource actor* MUST NOT send a `Grant` to actor *A*, even if the
     `Accept` is authorized
  ii. The *resource actor* MAY publish and deliver a `Reject` activity, at
      least to the actor that sent the `Accept`, where [object][] specifies
      the `Accept`

d. It SHOULD publish and deliver a Reject activity, at least to actor A, where object specifies the Join that actor A sent

So, once a Join is rejected (using an authorized Reject), it cannot be accepted. But actor A MAY send a new Join, which could then possibly get accepted.

Example

Aviva creates a new Repository for her 3D Tree Growth Simulation software:

{
    "@context": [
        "https://www.w3.org/ns/activitystreams",
        "https://forgefed.org/ns"
    ],
    "id": "https://forge.community/users/aviva/outbox/oU6QGAqr-create-treesim",
    "type": "Create",
    "actor": "https://forge.community/users/aviva",
    "to": [
        "https://forge.community/users/aviva/followers"
    ],
    "object": {
        "id": "https://forge.community/repos/treesim",
        "type": "Repository",
        "name": "Tree Growth 3D Simulation",
        "summary": "A graphical simulation of trees growing"
    }
}

The newly created treesim Repository automatically sends back a Grant to Aviva, allowing her full access to the repo:

{
    "@context": [
        "https://www.w3.org/ns/activitystreams",
        "https://forgefed.org/ns"
    ],
    "id": "https://forge.community/repos/treesim/outbox/2NwyPWMX-grant-admin-to-aviva",
    "type": "Grant",
    "actor": "https://forge.community/repos/treesim",
    "to": [
        "https://forge.community/aviva",
        "https://forge.community/aviva/followers"
    ],
    "object": "https://roles.example/admin",
    "context": "https://forge.community/repos/treesim",
    "target": "https://forge.community/aviva",
    "fulfills": "https://forge.community/users/aviva/outbox/oU6QGAqr-create-treesim"
}

Aviva can now use this Grant, e.g. to update the repo's description text:

{
    "@context": [
        "https://www.w3.org/ns/activitystreams",
        "https://forgefed.org/ns"
    ],
    "id": "https://forge.community/users/aviva/outbox/RmTygyuj",
    "type": "Update",
    "actor": "https://forge.community/users/aviva",
    "to": [
        "https://forge.community/users/aviva/followers",
        "https://forge.community/repos/treesim",
        "https://forge.community/repos/treesim/followers"
    ],
    "object": {
        "id": "https://forge.community/repos/treesim",
        "type": "Repository",
        "name": "Tree Growth 3D Simulation",
        "summary": "Tree growth 3D simulator for my nature exploration game"
    },
    "capability": "https://forge.community/repos/treesim/outbox/2NwyPWMX-grant-admin-to-aviva"
}

Aviva wants to keep track of events related to the treesim repo:

{
    "@context": "https://www.w3.org/ns/activitystreams",
    "id": "https://forge.community/users/aviva/outbox/gqtpAhm2",
    "type": "Follow",
    "actor": "https://forge.community/users/aviva",
    "to": "https://forge.community/repos/treesim",
    "object": "https://forge.community/repos/treesim",
}

Aviva can invite Luke to have access to the treesim repo:

{
    "@context": [
        "https://www.w3.org/ns/activitystreams",
        "https://forgefed.org/ns"
    ],
    "id": "https://forge.community/users/aviva/outbox/qfrEGqnC-invite-luke",
    "type": "Invite",
    "actor": "https://forge.community/users/aviva",
    "to": [
        "https://forge.community/aviva/followers",
        "https://forge.community/repos/treesim",
        "https://forge.community/repos/treesim/followers",
        "https://software.site/people/luke",
        "https://software.site/people/luke/followers"
    ],
    "instrument": "https://roles.example/maintainer",
    "target": "https://forge.community/repos/treesim",
    "object": "https://software.site/people/luke",
    "capability": "https://forge.community/repos/treesim/outbox/2NwyPWMX-grant-admin-to-aviva"
}

And it appears that Luke accepts the invitation:

{
    "@context": [
        "https://www.w3.org/ns/activitystreams",
        "https://forgefed.org/ns"
    ],
    "id": "https://software.site/people/luke/activities/mEYYmt8u",
    "type": "Accept",
    "actor": "https://software.site/people/luke",
    "to": [
        "https://forge.community/aviva",
        "https://forge.community/aviva/followers",
        "https://forge.community/repos/treesim",
        "https://forge.community/repos/treesim/followers",
        "https://software.site/people/luke/followers"
    ],
    "object": "https://forge.community/users/aviva/outbox/qfrEGqnC-invite-luke"
}

Seeing the Invite and the Accept, the treesim repo sends Luke a Grant giving him the access that Aviva offered, and which he accepted:

{
    "@context": [
        "https://www.w3.org/ns/activitystreams",
        "https://forgefed.org/ns"
    ],
    "id": "https://forge.community/repos/treesim/outbox/D5uod3pz-grant-maintainer-to-luke",
    "type": "Grant",
    "actor": "https://forge.community/repos/treesim",
    "to": [
        "https://forge.community/aviva",
        "https://forge.community/aviva/followers",
        "https://forge.community/repos/treesim/followers",
        "https://software.site/people/luke",
        "https://software.site/people/luke/followers"
    ],
    "object": "https://roles.example/maintainer",
    "context": "https://forge.community/repos/treesim",
    "target": "https://software.site/people/luke",
    "fulfills": "https://forge.community/users/aviva/outbox/qfrEGqnC-invite-luke"
}

Luke can now use this Grant, e.g. to delete some old obsolete branch of the treesim repo:

{
    "@context": [
        "https://www.w3.org/ns/activitystreams",
        "https://forgefed.org/ns"
    ],
    "id": "https://software.site/people/luke/activities/vShj2aIe",
    "type": "Delete",
    "actor": "https://software.site/people/luke",
    "to": [
        "https://forge.community/repos/treesim",
        "https://forge.community/repos/treesim/followers",
        "https://software.site/people/luke/followers"
    ],
    "object": "https://forge.community/repos/treesim/branches/fixes-for-release-0.1.3",
    "origin": "https://forge.community/repos/treesim",
    "capability": "https://forge.community/repos/treesim/outbox/D5uod3pz-grant-maintainer-to-luke"
}

Celine requests to have developer access to the treesim repo:

{
    "@context": [
        "https://www.w3.org/ns/activitystreams",
        "https://forgefed.org/ns"
    ],
    "id": "https://dev.online/@celine/sent/v5Qvd6bB-celine-join",
    "type": "Join",
    "actor": ""https://dev.online/@celine",
    "to": [
        "https://forge.community/repos/treesim",
        "https://forge.community/repos/treesim/followers",
        "https://dev.online/@celine/followers"
    ],
    "object": ""https://forge.community/repos/treesim",
    "instrument": "https://roles.example/developer"
}

Aviva sees the Join request, talks with Celine and decides to approve her request:

{
    "@context": [
        "https://www.w3.org/ns/activitystreams",
        "https://forgefed.org/ns"
    ],
    "id": "https://forge.community/users/aviva/outbox/PzRtDydu",
    "type": "Accept",
    "actor": "https://forge.community/users/aviva",
    "to": [
        "https://forge.community/repos/treesim",
        "https://forge.community/repos/treesim/followers",
        "https://dev.online/@celine",
        "https://dev.online/@celine/followers"
    ],
    "object": "https://dev.online/@celine/sent/v5Qvd6bB-celine-join",
    "capability": "https://forge.community/repos/treesim/outbox/2NwyPWMX-grant-admin-to-aviva"
}

Seeing the Join and the Accept, the treesim repo sends Celine a Grant giving her the access that she requested, and which Aviva approved:

{
    "@context": [
        "https://www.w3.org/ns/activitystreams",
        "https://forgefed.org/ns"
    ],
    "id": "https://forge.community/repos/treesim/outbox/D5uod3pz-grant-developer-to-celine",
    "type": "Grant",
    "actor": "https://forge.community/repos/treesim",
    "to": [
        "https://forge.community/aviva",
        "https://forge.community/repos/treesim/followers",
        "https://dev.online/@celine",
        "https://dev.online/@celine/followers"
    ],
    "object": "https://roles.example/developer",
    "context": "https://forge.community/repos/treesim",
    "target": "https://dev.online/@celine",
    "fulfills": "https://dev.online/@celine/sent/v5Qvd6bB-celine-join"
}

Celine can now use this Grant to access the treesim repo.

Acknowledgements