matrix-org.dendrite/roomserver/internal/input/input_membership.go

268 lines
8.6 KiB
Go

// Copyright 2017 Vector Creations Ltd
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package input
import (
"context"
"fmt"
"github.com/matrix-org/gomatrixserverlib/spec"
"github.com/matrix-org/dendrite/internal"
"github.com/matrix-org/dendrite/roomserver/api"
"github.com/matrix-org/dendrite/roomserver/internal/helpers"
"github.com/matrix-org/dendrite/roomserver/storage/shared"
"github.com/matrix-org/dendrite/roomserver/storage/tables"
"github.com/matrix-org/dendrite/roomserver/types"
)
// updateMembership updates the current membership and the invites for each
// user affected by a change in the current state of the room.
// Returns a list of output events to write to the kafka log to inform the
// consumers about the invites added or retired by the change in current state.
func (r *Inputer) updateMemberships(
ctx context.Context,
updater *shared.RoomUpdater,
removed, added []types.StateEntry,
) ([]api.OutputEvent, error) {
trace, ctx := internal.StartRegion(ctx, "updateMemberships")
defer trace.EndRegion()
changes := membershipChanges(removed, added)
var eventNIDs []types.EventNID
for _, change := range changes {
if change.addedEventNID != 0 {
eventNIDs = append(eventNIDs, change.addedEventNID)
}
if change.removedEventNID != 0 {
eventNIDs = append(eventNIDs, change.removedEventNID)
}
}
// Load the event JSON so we can look up the "membership" key.
// TODO: Maybe add a membership key to the events table so we can load that
// key without having to load the entire event JSON?
events, err := updater.Events(ctx, "", eventNIDs)
if err != nil {
return nil, err
}
var updates []api.OutputEvent
for _, change := range changes {
var ae *types.Event
var re *types.Event
targetUserNID := change.EventStateKeyNID
if change.removedEventNID != 0 {
re, _ = helpers.EventMap(events).Lookup(change.removedEventNID)
}
if change.addedEventNID != 0 {
ae, _ = helpers.EventMap(events).Lookup(change.addedEventNID)
}
if updates, err = r.updateMembership(ctx, updater, targetUserNID, re, ae, updates); err != nil {
return nil, err
}
}
return updates, nil
}
func (r *Inputer) updateMembership(
ctx context.Context,
updater *shared.RoomUpdater,
targetUserNID types.EventStateKeyNID,
remove, add *types.Event,
updates []api.OutputEvent,
) ([]api.OutputEvent, error) {
var err error
// Default the membership to Leave if no event was added or removed.
newMembership := spec.Leave
if add != nil {
newMembership, err = add.Membership()
if err != nil {
return nil, err
}
}
var targetLocal bool
if add != nil {
targetLocal = r.isLocalTarget(ctx, add)
}
mu, err := updater.MembershipUpdater(targetUserNID, targetLocal)
if err != nil {
return nil, err
}
// In an ideal world, we shouldn't ever have "add" be nil and "remove" be
// set, as this implies that we're deleting a state event without replacing
// it (a thing that ordinarily shouldn't happen in Matrix). However, state
// resets are sadly a thing occasionally and we have to account for that.
// Beforehand there used to be a check here which stopped dead if we hit
// this scenario, but that meant that the membership table got out of sync
// after a state reset, often thinking that the user was still joined to
// the room even though the room state said otherwise, and this would prevent
// the user from being able to attempt to rejoin the room without modifying
// the database. So instead we're going to remove the membership from the
// database altogether, so that it doesn't create future problems.
if add == nil && remove != nil {
return nil, mu.Delete()
}
switch newMembership {
case spec.Invite:
return helpers.UpdateToInviteMembership(mu, add, updates, updater.RoomVersion())
case spec.Join:
return updateToJoinMembership(mu, add, updates)
case spec.Leave, spec.Ban:
return updateToLeaveMembership(mu, add, newMembership, updates)
case spec.Knock:
return updateToKnockMembership(mu, add, updates)
default:
panic(fmt.Errorf(
"input: membership %q is not one of the allowed values", newMembership,
))
}
}
func (r *Inputer) isLocalTarget(ctx context.Context, event *types.Event) bool {
isTargetLocalUser := false
if statekey := event.StateKey(); statekey != nil {
userID, err := r.Queryer.QueryUserIDForSender(ctx, event.RoomID(), spec.SenderID(*statekey))
if err != nil || userID == nil {
return isTargetLocalUser
}
isTargetLocalUser = userID.Domain() == r.ServerName
}
return isTargetLocalUser
}
func updateToJoinMembership(
mu *shared.MembershipUpdater, add *types.Event, updates []api.OutputEvent,
) ([]api.OutputEvent, error) {
// When we mark a user as being joined we will invalidate any invites that
// are active for that user. We notify the consumers that the invites have
// been retired using a special event, even though they could infer this
// by studying the state changes in the room event stream.
_, retired, err := mu.Update(tables.MembershipStateJoin, add)
if err != nil {
return nil, err
}
for _, eventID := range retired {
updates = append(updates, api.OutputEvent{
Type: api.OutputTypeRetireInviteEvent,
RetireInviteEvent: &api.OutputRetireInviteEvent{
EventID: eventID,
RoomID: add.RoomID().String(),
Membership: spec.Join,
RetiredByEventID: add.EventID(),
TargetSenderID: spec.SenderID(*add.StateKey()),
},
})
}
return updates, nil
}
func updateToLeaveMembership(
mu *shared.MembershipUpdater, add *types.Event,
newMembership string, updates []api.OutputEvent,
) ([]api.OutputEvent, error) {
// When we mark a user as having left we will invalidate any invites that
// are active for that user. We notify the consumers that the invites have
// been retired using a special event, even though they could infer this
// by studying the state changes in the room event stream.
_, retired, err := mu.Update(tables.MembershipStateLeaveOrBan, add)
if err != nil {
return nil, err
}
for _, eventID := range retired {
updates = append(updates, api.OutputEvent{
Type: api.OutputTypeRetireInviteEvent,
RetireInviteEvent: &api.OutputRetireInviteEvent{
EventID: eventID,
RoomID: add.RoomID().String(),
Membership: newMembership,
RetiredByEventID: add.EventID(),
TargetSenderID: spec.SenderID(*add.StateKey()),
},
})
}
return updates, nil
}
func updateToKnockMembership(
mu *shared.MembershipUpdater, add *types.Event, updates []api.OutputEvent,
) ([]api.OutputEvent, error) {
if _, _, err := mu.Update(tables.MembershipStateKnock, add); err != nil {
return nil, err
}
return updates, nil
}
// membershipChanges pairs up the membership state changes.
func membershipChanges(removed, added []types.StateEntry) []stateChange {
changes := pairUpChanges(removed, added)
var result []stateChange
for _, c := range changes {
if c.EventTypeNID == types.MRoomMemberNID {
result = append(result, c)
}
}
return result
}
type stateChange struct {
types.StateKeyTuple
removedEventNID types.EventNID
addedEventNID types.EventNID
}
// pairUpChanges pairs up the state events added and removed for each type,
// state key tuple.
func pairUpChanges(removed, added []types.StateEntry) []stateChange {
tuples := make(map[types.StateKeyTuple]stateChange)
changes := []stateChange{}
// First, go through the newly added state entries.
for _, add := range added {
if change, ok := tuples[add.StateKeyTuple]; ok {
// If we already have an entry, update it.
change.addedEventNID = add.EventNID
tuples[add.StateKeyTuple] = change
} else {
// Otherwise, create a new entry.
tuples[add.StateKeyTuple] = stateChange{add.StateKeyTuple, 0, add.EventNID}
}
}
// Now go through the removed state entries.
for _, remove := range removed {
if change, ok := tuples[remove.StateKeyTuple]; ok {
// If we already have an entry, update it.
change.removedEventNID = remove.EventNID
tuples[remove.StateKeyTuple] = change
} else {
// Otherwise, create a new entry.
tuples[remove.StateKeyTuple] = stateChange{remove.StateKeyTuple, remove.EventNID, 0}
}
}
// Now return the changes as an array.
for _, change := range tuples {
changes = append(changes, change)
}
return changes
}