gotosocial/vendor/github.com/superseriousbusiness/activity/pub/database.go
kim cc5f2e98b7
[bugfix] Fix possible race condition in federatingdb (#490)
Signed-off-by: kim <grufwub@gmail.com>
2022-04-28 11:18:27 +02:00

153 lines
7 KiB
Go

package pub
import (
"context"
"net/url"
"github.com/superseriousbusiness/activity/streams/vocab"
)
type Database interface {
// Lock takes a lock for the object at the specified id. If an error
// is returned, the lock must not have been taken.
//
// The lock must be able to succeed for an id that does not exist in
// the database. This means acquiring the lock does not guarantee the
// entry exists in the database.
//
// Locks are encouraged to be lightweight and in the Go layer, as some
// processes require tight loops acquiring and releasing locks.
//
// Used to ensure race conditions in multiple requests do not occur.
Lock(c context.Context, id *url.URL) (unlock func(), err error)
// InboxContains returns true if the OrderedCollection at 'inbox'
// contains the specified 'id'.
//
// The library makes this call only after acquiring a lock first.
InboxContains(c context.Context, inbox, id *url.URL) (contains bool, err error)
// GetInbox returns the first ordered collection page of the outbox at
// the specified IRI, for prepending new items.
//
// The library makes this call only after acquiring a lock first.
GetInbox(c context.Context, inboxIRI *url.URL) (inbox vocab.ActivityStreamsOrderedCollectionPage, err error)
// SetInbox saves the inbox value given from GetInbox, with new items
// prepended. Note that the new items must not be added as independent
// database entries. Separate calls to Create will do that.
//
// The library makes this call only after acquiring a lock first.
SetInbox(c context.Context, inbox vocab.ActivityStreamsOrderedCollectionPage) error
// Owns returns true if the database has an entry for the IRI and it
// exists in the database.
//
// The library makes this call only after acquiring a lock first.
Owns(c context.Context, id *url.URL) (owns bool, err error)
// ActorForOutbox fetches the actor's IRI for the given outbox IRI.
//
// The library makes this call only after acquiring a lock first.
ActorForOutbox(c context.Context, outboxIRI *url.URL) (actorIRI *url.URL, err error)
// ActorForInbox fetches the actor's IRI for the given outbox IRI.
//
// The library makes this call only after acquiring a lock first.
ActorForInbox(c context.Context, inboxIRI *url.URL) (actorIRI *url.URL, err error)
// OutboxForInbox fetches the corresponding actor's outbox IRI for the
// actor's inbox IRI.
//
// The library makes this call only after acquiring a lock first.
OutboxForInbox(c context.Context, inboxIRI *url.URL) (outboxIRI *url.URL, err error)
// InboxesForIRI fetches inboxes corresponding to the given iri.
// This allows your server to skip remote dereferencing of iris
// in order to speed up message delivery, if desired.
//
// It is acceptable to just return nil or an empty slice for the inboxIRIs,
// if you don't know the inbox iri, or you don't wish to use this feature.
// In this case, the library will attempt to resolve inboxes of the iri
// by remote dereferencing instead.
//
// If the input iri is the iri of an Actor, then the inbox for the actor
// should be returned as a single-entry slice.
//
// If the input iri is a Collection (such as a Collection of followers),
// then each follower inbox IRI should be returned in the inboxIRIs slice.
//
// The library makes this call only after acquiring a lock first.
InboxesForIRI(c context.Context, iri *url.URL) (inboxIRIs []*url.URL, err error)
// Exists returns true if the database has an entry for the specified
// id. It may not be owned by this application instance.
//
// The library makes this call only after acquiring a lock first.
Exists(c context.Context, id *url.URL) (exists bool, err error)
// Get returns the database entry for the specified id.
//
// The library makes this call only after acquiring a lock first.
Get(c context.Context, id *url.URL) (value vocab.Type, err error)
// Create adds a new entry to the database which must be able to be
// keyed by its id.
//
// Note that Activity values received from federated peers may also be
// created in the database this way if the Federating Protocol is
// enabled. The client may freely decide to store only the id instead of
// the entire value.
//
// The library makes this call only after acquiring a lock first.
//
// Under certain conditions and network activities, Create may be called
// multiple times for the same ActivityStreams object.
Create(c context.Context, asType vocab.Type) error
// Update sets an existing entry to the database based on the value's
// id.
//
// Note that Activity values received from federated peers may also be
// updated in the database this way if the Federating Protocol is
// enabled. The client may freely decide to store only the id instead of
// the entire value.
//
// The library makes this call only after acquiring a lock first.
Update(c context.Context, asType vocab.Type) error
// Delete removes the entry with the given id.
//
// Delete is only called for federated objects. Deletes from the Social
// Protocol instead call Update to create a Tombstone.
//
// The library makes this call only after acquiring a lock first.
Delete(c context.Context, id *url.URL) error
// GetOutbox returns the first ordered collection page of the outbox
// at the specified IRI, for prepending new items.
//
// The library makes this call only after acquiring a lock first.
GetOutbox(c context.Context, outboxIRI *url.URL) (outbox vocab.ActivityStreamsOrderedCollectionPage, err error)
// SetOutbox saves the outbox value given from GetOutbox, with new items
// prepended. Note that the new items must not be added as independent
// database entries. Separate calls to Create will do that.
//
// The library makes this call only after acquiring a lock first.
SetOutbox(c context.Context, outbox vocab.ActivityStreamsOrderedCollectionPage) error
// NewID creates a new IRI id for the provided activity or object. The
// implementation does not need to set the 'id' property and simply
// needs to determine the value.
//
// The go-fed library will handle setting the 'id' property on the
// activity or object provided with the value returned.
NewID(c context.Context, t vocab.Type) (id *url.URL, err error)
// Followers obtains the Followers Collection for an actor with the
// given id.
//
// If modified, the library will then call Update.
//
// The library makes this call only after acquiring a lock first.
Followers(c context.Context, actorIRI *url.URL) (followers vocab.ActivityStreamsCollection, err error)
// Following obtains the Following Collection for an actor with the
// given id.
//
// If modified, the library will then call Update.
//
// The library makes this call only after acquiring a lock first.
Following(c context.Context, actorIRI *url.URL) (following vocab.ActivityStreamsCollection, err error)
// Liked obtains the Liked Collection for an actor with the
// given id.
//
// If modified, the library will then call Update.
//
// The library makes this call only after acquiring a lock first.
Liked(c context.Context, actorIRI *url.URL) (liked vocab.ActivityStreamsCollection, err error)
}