activity/pub/federating_wrapped_callbacks.go

898 行
27 KiB
Go

package pub
import (
"context"
"encoding/json"
"fmt"
"github.com/go-fed/activity/streams"
"github.com/go-fed/activity/streams/vocab"
"net/url"
)
// OnFollowBehavior enumerates the different default actions that the go-fed
// library can provide when receiving a Follow Activity from a peer.
type OnFollowBehavior int
const (
// OnFollowDoNothing does not take any action when a Follow Activity
// is received.
OnFollowDoNothing OnFollowBehavior = iota
// OnFollowAutomaticallyAccept triggers the side effect of sending an
// Accept of this Follow request in response.
OnFollowAutomaticallyAccept
// OnFollowAutomaticallyAccept triggers the side effect of sending a
// Reject of this Follow request in response.
OnFollowAutomaticallyReject
)
// FederatingWrappedCallbacks lists the callback functions that already have
// some side effect behavior provided by the pub library.
//
// These functions are wrapped for the Federating Protocol.
type FederatingWrappedCallbacks struct {
// Create handles additional side effects for the Create ActivityStreams
// type, specific to the application using go-fed.
//
// The wrapping callback for the Federating Protocol ensures the
// 'object' property is created in the database.
//
// Create calls Create for each object in the federated Activity.
Create func(context.Context, vocab.ActivityStreamsCreate) error
// Update handles additional side effects for the Update ActivityStreams
// type, specific to the application using go-fed.
//
// The wrapping callback for the Federating Protocol ensures the
// 'object' property is updated in the database.
//
// Update calls Update on the federated entry from the database, with a
// new value.
Update func(context.Context, vocab.ActivityStreamsUpdate) error
// Delete handles additional side effects for the Delete ActivityStreams
// type, specific to the application using go-fed.
//
// Delete removes the federated entry from the database.
Delete func(context.Context, vocab.ActivityStreamsDelete) error
// Follow handles additional side effects for the Follow ActivityStreams
// type, specific to the application using go-fed.
//
// The wrapping function can have one of several default behaviors,
// depending on the value of the OnFollow setting.
Follow func(context.Context, vocab.ActivityStreamsFollow) error
// OnFollow determines what action to take for this particular callback
// if a Follow Activity is handled.
OnFollow OnFollowBehavior
// Accept handles additional side effects for the Accept ActivityStreams
// type, specific to the application using go-fed.
//
// The wrapping function determines if this 'Accept' is in response to a
// 'Follow'. If so, then the 'actor' is added to the original 'actor's
// 'following' collection.
//
// Otherwise, no side effects are done by go-fed.
Accept func(context.Context, vocab.ActivityStreamsAccept) error
// Reject handles additional side effects for the Reject ActivityStreams
// type, specific to the application using go-fed.
//
// The wrapping function has no default side effects. However, if this
// 'Reject' is in response to a 'Follow' then the client MUST NOT go
// forward with adding the 'actor' to the original 'actor's 'following'
// collection by the client application.
Reject func(context.Context, vocab.ActivityStreamsReject) error
// Add handles additional side effects for the Add ActivityStreams
// type, specific to the application using go-fed.
//
// The wrapping function will add the 'object' IRIs to a specific
// 'target' collection if the 'target' collection(s) live on this
// server.
Add func(context.Context, vocab.ActivityStreamsAdd) error
// Remove handles additional side effects for the Remove ActivityStreams
// type, specific to the application using go-fed.
//
// The wrapping function will remove all 'object' IRIs from a specific
// 'target' collection if the 'target' collection(s) live on this
// server.
Remove func(context.Context, vocab.ActivityStreamsRemove) error
// Like handles additional side effects for the Like ActivityStreams
// type, specific to the application using go-fed.
//
// The wrapping function will add the activity to the "likes" collection
// on all 'object' targets owned by this server.
Like func(context.Context, vocab.ActivityStreamsLike) error
// Announce handles additional side effects for the Announce
// ActivityStreams type, specific to the application using go-fed.
//
// The wrapping function will add the activity to the "shares"
// collection on all 'object' targets owned by this server.
Announce func(context.Context, vocab.ActivityStreamsAnnounce) error
// Undo handles additional side effects for the Undo ActivityStreams
// type, specific to the application using go-fed.
//
// The wrapping function ensures the 'actor' on the 'Undo'
// is be the same as the 'actor' on all Activities being undone.
// It enforces that the actors on the Undo must correspond to all of the
// 'object' actors in some manner.
//
// It is expected that the application will implement the proper
// reversal of activities that are being undone.
Undo func(context.Context, vocab.ActivityStreamsUndo) error
// Block handles additional side effects for the Block ActivityStreams
// type, specific to the application using go-fed.
//
// The wrapping function provides no default side effects. It simply
// calls the wrapped function. However, note that Blocks should not be
// received from a federated peer, as delivering Blocks explicitly
// deviates from the original ActivityPub specification.
Block func(context.Context, vocab.ActivityStreamsBlock) error
// Sidechannel data -- this is set at request handling time. These must
// be set before the callbacks are used.
// db is the Database the FederatingWrappedCallbacks should use.
db Database
// inboxIRI is the inboxIRI that is handling this callback.
inboxIRI *url.URL
// addNewIds creates new 'id' entries on an activity and its objects if
// it is a Create activity.
addNewIds func(c context.Context, activity Activity) error
// deliver delivers an outgoing message.
deliver func(c context.Context, outboxIRI *url.URL, activity Activity) error
// newTransport creates a new Transport.
newTransport func(c context.Context, actorBoxIRI *url.URL, gofedAgent string) (t Transport, err error)
}
// callbacks returns the WrappedCallbacks members into a single interface slice
// for use in streams.Resolver callbacks.
//
// If the given functions have a type that collides with the default behavior,
// then disable our default behavior
func (w FederatingWrappedCallbacks) callbacks(fns []interface{}) []interface{} {
enableCreate := true
enableUpdate := true
enableDelete := true
enableFollow := true
enableAccept := true
enableReject := true
enableAdd := true
enableRemove := true
enableLike := true
enableAnnounce := true
enableUndo := true
enableBlock := true
for _, fn := range fns {
switch fn.(type) {
default:
continue
case func(context.Context, vocab.ActivityStreamsCreate) error:
enableCreate = false
case func(context.Context, vocab.ActivityStreamsUpdate) error:
enableUpdate = false
case func(context.Context, vocab.ActivityStreamsDelete) error:
enableDelete = false
case func(context.Context, vocab.ActivityStreamsFollow) error:
enableFollow = false
case func(context.Context, vocab.ActivityStreamsAccept) error:
enableAccept = false
case func(context.Context, vocab.ActivityStreamsReject) error:
enableReject = false
case func(context.Context, vocab.ActivityStreamsAdd) error:
enableAdd = false
case func(context.Context, vocab.ActivityStreamsRemove) error:
enableRemove = false
case func(context.Context, vocab.ActivityStreamsLike) error:
enableLike = false
case func(context.Context, vocab.ActivityStreamsAnnounce) error:
enableAnnounce = false
case func(context.Context, vocab.ActivityStreamsUndo) error:
enableUndo = false
case func(context.Context, vocab.ActivityStreamsBlock) error:
enableBlock = false
}
}
if enableCreate {
fns = append(fns, w.create)
}
if enableUpdate {
fns = append(fns, w.update)
}
if enableDelete {
fns = append(fns, w.deleteFn)
}
if enableFollow {
fns = append(fns, w.follow)
}
if enableAccept {
fns = append(fns, w.accept)
}
if enableReject {
fns = append(fns, w.reject)
}
if enableAdd {
fns = append(fns, w.add)
}
if enableRemove {
fns = append(fns, w.remove)
}
if enableLike {
fns = append(fns, w.like)
}
if enableAnnounce {
fns = append(fns, w.announce)
}
if enableUndo {
fns = append(fns, w.undo)
}
if enableBlock {
fns = append(fns, w.block)
}
return fns
}
// create implements the federating Create activity side effects.
func (w FederatingWrappedCallbacks) create(c context.Context, a vocab.ActivityStreamsCreate) error {
op := a.GetActivityStreamsObject()
if op == nil || op.Len() == 0 {
return ErrObjectRequired
}
// Create anonymous loop function to be able to properly scope the defer
// for the database lock at each iteration.
loopFn := func(iter vocab.ActivityStreamsObjectPropertyIterator) error {
t := iter.GetType()
if t == nil && iter.IsIRI() {
// Attempt to dereference the IRI instead
tport, err := w.newTransport(c, w.inboxIRI, goFedUserAgent())
if err != nil {
return err
}
b, err := tport.Dereference(c, iter.GetIRI())
if err != nil {
return err
}
var m map[string]interface{}
if err = json.Unmarshal(b, &m); err != nil {
return err
}
t, err = streams.ToType(c, m)
if err != nil {
return err
}
} else if t == nil {
return fmt.Errorf("cannot handle federated create: object is neither a value nor IRI")
}
id, err := GetId(t)
if err != nil {
return err
}
err = w.db.Lock(c, id)
if err != nil {
return err
}
defer w.db.Unlock(c, id)
if err := w.db.Create(c, t); err != nil {
return err
}
return nil
}
for iter := op.Begin(); iter != op.End(); iter = iter.Next() {
if err := loopFn(iter); err != nil {
return err
}
}
if w.Create != nil {
return w.Create(c, a)
}
return nil
}
// update implements the federating Update activity side effects.
func (w FederatingWrappedCallbacks) update(c context.Context, a vocab.ActivityStreamsUpdate) error {
op := a.GetActivityStreamsObject()
if op == nil || op.Len() == 0 {
return ErrObjectRequired
}
if err := mustHaveActivityOriginMatchObjects(a); err != nil {
return err
}
// Create anonymous loop function to be able to properly scope the defer
// for the database lock at each iteration.
loopFn := func(iter vocab.ActivityStreamsObjectPropertyIterator) error {
t := iter.GetType()
if t == nil {
return fmt.Errorf("update requires an object to be wholly provided")
}
id, err := GetId(t)
if err != nil {
return err
}
err = w.db.Lock(c, id)
if err != nil {
return err
}
defer w.db.Unlock(c, id)
if err := w.db.Update(c, t); err != nil {
return err
}
return nil
}
for iter := op.Begin(); iter != op.End(); iter = iter.Next() {
if err := loopFn(iter); err != nil {
return err
}
}
if w.Update != nil {
return w.Update(c, a)
}
return nil
}
// deleteFn implements the federating Delete activity side effects.
func (w FederatingWrappedCallbacks) deleteFn(c context.Context, a vocab.ActivityStreamsDelete) error {
op := a.GetActivityStreamsObject()
if op == nil || op.Len() == 0 {
return ErrObjectRequired
}
if err := mustHaveActivityOriginMatchObjects(a); err != nil {
return err
}
// Create anonymous loop function to be able to properly scope the defer
// for the database lock at each iteration.
loopFn := func(iter vocab.ActivityStreamsObjectPropertyIterator) error {
id, err := ToId(iter)
if err != nil {
return err
}
err = w.db.Lock(c, id)
if err != nil {
return err
}
defer w.db.Unlock(c, id)
if err := w.db.Delete(c, id); err != nil {
return err
}
return nil
}
for iter := op.Begin(); iter != op.End(); iter = iter.Next() {
if err := loopFn(iter); err != nil {
return err
}
}
if w.Delete != nil {
return w.Delete(c, a)
}
return nil
}
// follow implements the federating Follow activity side effects.
func (w FederatingWrappedCallbacks) follow(c context.Context, a vocab.ActivityStreamsFollow) error {
op := a.GetActivityStreamsObject()
if op == nil || op.Len() == 0 {
return ErrObjectRequired
}
// Check that we own at least one of the 'object' properties, and ensure
// it is to the actor that owns this inbox.
//
// If not then don't send a response. It was federated to us as an FYI,
// by mistake, or some other reason.
if err := w.db.Lock(c, w.inboxIRI); err != nil {
return err
}
// WARNING: Unlock not deferred.
actorIRI, err := w.db.ActorForInbox(c, w.inboxIRI)
if err != nil {
w.db.Unlock(c, w.inboxIRI)
return err
}
w.db.Unlock(c, w.inboxIRI)
// Unlock must be called by now and every branch above.
isMe := false
if w.OnFollow != OnFollowDoNothing {
for iter := op.Begin(); iter != op.End(); iter = iter.Next() {
id, err := ToId(iter)
if err != nil {
return err
}
if id.String() == actorIRI.String() {
isMe = true
break
}
}
}
if isMe {
// Prepare the response.
var response Activity
if w.OnFollow == OnFollowAutomaticallyAccept {
response = streams.NewActivityStreamsAccept()
} else if w.OnFollow == OnFollowAutomaticallyReject {
response = streams.NewActivityStreamsReject()
} else {
return fmt.Errorf("unknown OnFollowBehavior: %d", w.OnFollow)
}
// Set us as the 'actor'.
me := streams.NewActivityStreamsActorProperty()
response.SetActivityStreamsActor(me)
me.AppendIRI(actorIRI)
// Set the Follow as the 'object' property.
op := streams.NewActivityStreamsObjectProperty()
response.SetActivityStreamsObject(op)
op.AppendActivityStreamsFollow(a)
// Add all actors on the original Follow to the 'to' property.
recipients := make([]*url.URL, 0)
to := streams.NewActivityStreamsToProperty()
response.SetActivityStreamsTo(to)
followActors := a.GetActivityStreamsActor()
for iter := followActors.Begin(); iter != followActors.End(); iter = iter.Next() {
id, err := ToId(iter)
if err != nil {
return err
}
to.AppendIRI(id)
recipients = append(recipients, id)
}
if w.OnFollow == OnFollowAutomaticallyAccept {
// If automatically accepting, then also update our
// followers collection with the new actors.
//
// If automatically rejecting, do not update the
// followers collection.
if err := w.db.Lock(c, actorIRI); err != nil {
return err
}
// WARNING: Unlock not deferred.
followers, err := w.db.Followers(c, actorIRI)
if err != nil {
w.db.Unlock(c, actorIRI)
return err
}
items := followers.GetActivityStreamsItems()
for _, elem := range recipients {
items.PrependIRI(elem)
}
if err = w.db.Update(c, followers); err != nil {
w.db.Unlock(c, actorIRI)
return err
}
w.db.Unlock(c, actorIRI)
// Unlock must be called by now and every branch above.
}
// Lock without defer!
w.db.Lock(c, w.inboxIRI)
outboxIRI, err := w.db.OutboxForInbox(c, w.inboxIRI)
if err != nil {
w.db.Unlock(c, w.inboxIRI)
return err
}
w.db.Unlock(c, w.inboxIRI)
// Everything must be unlocked by now.
if err := w.addNewIds(c, response); err != nil {
return err
} else if err := w.deliver(c, outboxIRI, response); err != nil {
return err
}
}
if w.Follow != nil {
return w.Follow(c, a)
}
return nil
}
// accept implements the federating Accept activity side effects.
func (w FederatingWrappedCallbacks) accept(c context.Context, a vocab.ActivityStreamsAccept) error {
op := a.GetActivityStreamsObject()
if op != nil && op.Len() > 0 {
// Get this actor's id.
if err := w.db.Lock(c, w.inboxIRI); err != nil {
return err
}
// WARNING: Unlock not deferred.
actorIRI, err := w.db.ActorForInbox(c, w.inboxIRI)
if err != nil {
w.db.Unlock(c, w.inboxIRI)
return err
}
w.db.Unlock(c, w.inboxIRI)
// Unlock must be called by now and every branch above.
//
// Determine if we are in a follow on the 'object' property.
//
// TODO: Handle Accept multiple Follow.
var maybeMyFollowIRI *url.URL
for iter := op.Begin(); iter != op.End(); iter = iter.Next() {
t := iter.GetType()
if t == nil && iter.IsIRI() {
// Attempt to dereference the IRI instead
tport, err := w.newTransport(c, w.inboxIRI, goFedUserAgent())
if err != nil {
return err
}
b, err := tport.Dereference(c, iter.GetIRI())
if err != nil {
return err
}
var m map[string]interface{}
if err = json.Unmarshal(b, &m); err != nil {
return err
}
t, err = streams.ToType(c, m)
if err != nil {
return err
}
} else if t == nil {
return fmt.Errorf("cannot handle federated create: object is neither a value nor IRI")
}
// Ensure it is a Follow.
if !streams.IsOrExtendsActivityStreamsFollow(t) {
continue
}
follow, ok := t.(Activity)
if !ok {
return fmt.Errorf("a Follow in an Accept does not satisfy the Activity interface")
}
followId, err := GetId(follow)
if err != nil {
return err
}
// Ensure that we are one of the actors on the Follow.
actors := follow.GetActivityStreamsActor()
for iter := actors.Begin(); iter != actors.End(); iter = iter.Next() {
id, err := ToId(iter)
if err != nil {
return err
}
if id.String() == actorIRI.String() {
maybeMyFollowIRI = followId
break
}
}
// Continue breaking if we found ourselves
if maybeMyFollowIRI != nil {
break
}
}
// If we received an Accept whose 'object' is a Follow with an
// Accept that we sent, add to the following collection.
if maybeMyFollowIRI != nil {
// Verify our Follow request exists and the peer didn't
// fabricate it.
actors := a.GetActivityStreamsActor()
if actors == nil || actors.Len() == 0 {
return fmt.Errorf("an Accept with a Follow has no actors")
}
// This may be a duplicate check if we dereferenced the
// Follow above. TODO: Separate this logic to avoid
// redundancy.
//
// Use an anonymous function to properly scope the
// database lock, immediately call it.
err = func() error {
if err := w.db.Lock(c, maybeMyFollowIRI); err != nil {
return err
}
defer w.db.Unlock(c, maybeMyFollowIRI)
t, err := w.db.Get(c, maybeMyFollowIRI)
if err != nil {
return err
}
if !streams.IsOrExtendsActivityStreamsFollow(t) {
return fmt.Errorf("peer gave an Accept wrapping a Follow but provided a non-Follow id")
}
follow, ok := t.(Activity)
if !ok {
return fmt.Errorf("a Follow in an Accept does not satisfy the Activity interface")
}
// Ensure that we are one of the actors on the Follow.
ok = false
actors := follow.GetActivityStreamsActor()
for iter := actors.Begin(); iter != actors.End(); iter = iter.Next() {
id, err := ToId(iter)
if err != nil {
return err
}
if id.String() == actorIRI.String() {
ok = true
break
}
}
if !ok {
return fmt.Errorf("peer gave an Accept wrapping a Follow but we are not the actor on that Follow")
}
// Build map of original Accept actors
acceptActors := make(map[string]bool)
for iter := actors.Begin(); iter != actors.End(); iter = iter.Next() {
id, err := ToId(iter)
if err != nil {
return err
}
acceptActors[id.String()] = false
}
// Verify all actor(s) were on the original Follow.
followObj := follow.GetActivityStreamsObject()
for iter := followObj.Begin(); iter != followObj.End(); iter = iter.Next() {
id, err := ToId(iter)
if err != nil {
return err
}
if _, ok := acceptActors[id.String()]; ok {
acceptActors[id.String()] = true
}
}
for _, found := range acceptActors {
if !found {
return fmt.Errorf("peer gave an Accept wrapping a Follow but was not an object in the original Follow")
}
}
return nil
}()
if err != nil {
return err
}
// Add the peer to our following collection.
if err := w.db.Lock(c, actorIRI); err != nil {
return err
}
// WARNING: Unlock not deferred.
following, err := w.db.Following(c, actorIRI)
if err != nil {
w.db.Unlock(c, actorIRI)
return err
}
items := following.GetActivityStreamsItems()
for iter := actors.Begin(); iter != actors.End(); iter = iter.Next() {
id, err := ToId(iter)
if err != nil {
w.db.Unlock(c, actorIRI)
return err
}
items.PrependIRI(id)
}
if err = w.db.Update(c, following); err != nil {
w.db.Unlock(c, actorIRI)
return err
}
w.db.Unlock(c, actorIRI)
// Unlock must be called by now and every branch above.
}
}
if w.Accept != nil {
return w.Accept(c, a)
}
return nil
}
// reject implements the federating Reject activity side effects.
func (w FederatingWrappedCallbacks) reject(c context.Context, a vocab.ActivityStreamsReject) error {
if w.Reject != nil {
return w.Reject(c, a)
}
return nil
}
// add implements the federating Add activity side effects.
func (w FederatingWrappedCallbacks) add(c context.Context, a vocab.ActivityStreamsAdd) error {
op := a.GetActivityStreamsObject()
if op == nil || op.Len() == 0 {
return ErrObjectRequired
}
target := a.GetActivityStreamsTarget()
if target == nil || target.Len() == 0 {
return ErrTargetRequired
}
if err := add(c, op, target, w.db); err != nil {
return err
}
if w.Add != nil {
return w.Add(c, a)
}
return nil
}
// remove implements the federating Remove activity side effects.
func (w FederatingWrappedCallbacks) remove(c context.Context, a vocab.ActivityStreamsRemove) error {
op := a.GetActivityStreamsObject()
if op == nil || op.Len() == 0 {
return ErrObjectRequired
}
target := a.GetActivityStreamsTarget()
if target == nil || target.Len() == 0 {
return ErrTargetRequired
}
if err := remove(c, op, target, w.db); err != nil {
return err
}
if w.Remove != nil {
return w.Remove(c, a)
}
return nil
}
// like implements the federating Like activity side effects.
func (w FederatingWrappedCallbacks) like(c context.Context, a vocab.ActivityStreamsLike) error {
op := a.GetActivityStreamsObject()
if op == nil || op.Len() == 0 {
return ErrObjectRequired
}
id, err := GetId(a)
if err != nil {
return err
}
// Create anonymous loop function to be able to properly scope the defer
// for the database lock at each iteration.
loopFn := func(iter vocab.ActivityStreamsObjectPropertyIterator) error {
objId, err := ToId(iter)
if err != nil {
return err
}
if err := w.db.Lock(c, objId); err != nil {
return err
}
defer w.db.Unlock(c, objId)
if owns, err := w.db.Owns(c, objId); err != nil {
return err
} else if !owns {
return nil
}
t, err := w.db.Get(c, objId)
if err != nil {
return err
}
l, ok := t.(likeser)
if !ok {
return fmt.Errorf("cannot add Like to likes collection for type %T", t)
}
// Get 'likes' property on the object, creating default if
// necessary.
likes := l.GetActivityStreamsLikes()
if likes == nil {
likes = streams.NewActivityStreamsLikesProperty()
l.SetActivityStreamsLikes(likes)
}
// Get 'likes' value, defaulting to a collection.
likesT := likes.GetType()
if likesT == nil {
col := streams.NewActivityStreamsCollection()
likesT = col
likes.SetActivityStreamsCollection(col)
}
// Prepend the activity's 'id' on the 'likes' Collection or
// OrderedCollection.
if col, ok := likesT.(itemser); ok {
items := col.GetActivityStreamsItems()
if items == nil {
items = streams.NewActivityStreamsItemsProperty()
col.SetActivityStreamsItems(items)
}
items.PrependIRI(id)
} else if oCol, ok := likesT.(orderedItemser); ok {
oItems := oCol.GetActivityStreamsOrderedItems()
if oItems == nil {
oItems = streams.NewActivityStreamsOrderedItemsProperty()
oCol.SetActivityStreamsOrderedItems(oItems)
}
oItems.PrependIRI(id)
} else {
return fmt.Errorf("likes type is neither a Collection nor an OrderedCollection: %T", likesT)
}
err = w.db.Update(c, t)
if err != nil {
return err
}
return nil
}
for iter := op.Begin(); iter != op.End(); iter = iter.Next() {
if err := loopFn(iter); err != nil {
return err
}
}
if w.Like != nil {
return w.Like(c, a)
}
return nil
}
// announce implements the federating Announce activity side effects.
func (w FederatingWrappedCallbacks) announce(c context.Context, a vocab.ActivityStreamsAnnounce) error {
id, err := GetId(a)
if err != nil {
return err
}
op := a.GetActivityStreamsObject()
// Create anonymous loop function to be able to properly scope the defer
// for the database lock at each iteration.
loopFn := func(iter vocab.ActivityStreamsObjectPropertyIterator) error {
objId, err := ToId(iter)
if err != nil {
return err
}
if err := w.db.Lock(c, objId); err != nil {
return err
}
defer w.db.Unlock(c, objId)
if owns, err := w.db.Owns(c, objId); err != nil {
return err
} else if !owns {
return nil
}
t, err := w.db.Get(c, objId)
if err != nil {
return err
}
s, ok := t.(shareser)
if !ok {
return fmt.Errorf("cannot add Announce to Shares collection for type %T", t)
}
// Get 'shares' property on the object, creating default if
// necessary.
shares := s.GetActivityStreamsShares()
if shares == nil {
shares = streams.NewActivityStreamsSharesProperty()
s.SetActivityStreamsShares(shares)
}
// Get 'shares' value, defaulting to a collection.
sharesT := shares.GetType()
if sharesT == nil {
col := streams.NewActivityStreamsCollection()
sharesT = col
shares.SetActivityStreamsCollection(col)
}
// Prepend the activity's 'id' on the 'shares' Collection or
// OrderedCollection.
if col, ok := sharesT.(itemser); ok {
items := col.GetActivityStreamsItems()
if items == nil {
items = streams.NewActivityStreamsItemsProperty()
col.SetActivityStreamsItems(items)
}
items.PrependIRI(id)
} else if oCol, ok := sharesT.(orderedItemser); ok {
oItems := oCol.GetActivityStreamsOrderedItems()
if oItems == nil {
oItems = streams.NewActivityStreamsOrderedItemsProperty()
oCol.SetActivityStreamsOrderedItems(oItems)
}
oItems.PrependIRI(id)
} else {
return fmt.Errorf("shares type is neither a Collection nor an OrderedCollection: %T", sharesT)
}
err = w.db.Update(c, t)
if err != nil {
return err
}
return nil
}
for iter := op.Begin(); iter != op.End(); iter = iter.Next() {
if err := loopFn(iter); err != nil {
return err
}
}
if w.Announce != nil {
return w.Announce(c, a)
}
return nil
}
// undo implements the federating Undo activity side effects.
func (w FederatingWrappedCallbacks) undo(c context.Context, a vocab.ActivityStreamsUndo) error {
op := a.GetActivityStreamsObject()
if op == nil || op.Len() == 0 {
return ErrObjectRequired
}
actors := a.GetActivityStreamsActor()
if err := mustHaveActivityActorsMatchObjectActors(c, actors, op, w.newTransport, w.inboxIRI); err != nil {
return err
}
if w.Undo != nil {
return w.Undo(c, a)
}
return nil
}
// block implements the federating Block activity side effects.
func (w FederatingWrappedCallbacks) block(c context.Context, a vocab.ActivityStreamsBlock) error {
op := a.GetActivityStreamsObject()
if op == nil || op.Len() == 0 {
return ErrObjectRequired
}
if w.Block != nil {
return w.Block(c, a)
}
return nil
}