dendrite/roomserver/internal/alias.go

277 lines
8.1 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 internal
import (
"context"
"encoding/json"
"errors"
"fmt"
"time"
"github.com/matrix-org/dendrite/roomserver/api"
"github.com/matrix-org/gomatrixserverlib"
)
// RoomserverInternalAPIDatabase has the storage APIs needed to implement the alias API.
type RoomserverInternalAPIDatabase interface {
// Save a given room alias with the room ID it refers to.
// Returns an error if there was a problem talking to the database.
SetRoomAlias(ctx context.Context, alias string, roomID string, creatorUserID string) error
// Look up the room ID a given alias refers to.
// Returns an error if there was a problem talking to the database.
GetRoomIDForAlias(ctx context.Context, alias string) (string, error)
// Look up all aliases referring to a given room ID.
// Returns an error if there was a problem talking to the database.
GetAliasesForRoomID(ctx context.Context, roomID string) ([]string, error)
// Get the user ID of the creator of an alias.
// Returns an error if there was a problem talking to the database.
GetCreatorIDForAlias(ctx context.Context, alias string) (string, error)
// Remove a given room alias.
// Returns an error if there was a problem talking to the database.
RemoveRoomAlias(ctx context.Context, alias string) error
// Look up the room version for a given room.
GetRoomVersionForRoom(
ctx context.Context, roomID string,
) (gomatrixserverlib.RoomVersion, error)
}
// SetRoomAlias implements alias.RoomserverInternalAPI
func (r *RoomserverInternalAPI) SetRoomAlias(
ctx context.Context,
request *api.SetRoomAliasRequest,
response *api.SetRoomAliasResponse,
) error {
// Check if the alias isn't already referring to a room
roomID, err := r.DB.GetRoomIDForAlias(ctx, request.Alias)
if err != nil {
return err
}
if len(roomID) > 0 {
// If the alias already exists, stop the process
response.AliasExists = true
return nil
}
response.AliasExists = false
// Save the new alias
if err := r.DB.SetRoomAlias(ctx, request.Alias, request.RoomID, request.UserID); err != nil {
return err
}
// Send a m.room.aliases event with the updated list of aliases for this room
// At this point we've already committed the alias to the database so we
// shouldn't cancel this request.
// TODO: Ensure that we send unsent events when if server restarts.
return r.sendUpdatedAliasesEvent(context.TODO(), request.UserID, request.RoomID)
}
// GetRoomIDForAlias implements alias.RoomserverInternalAPI
func (r *RoomserverInternalAPI) GetRoomIDForAlias(
ctx context.Context,
request *api.GetRoomIDForAliasRequest,
response *api.GetRoomIDForAliasResponse,
) error {
// Look up the room ID in the database
roomID, err := r.DB.GetRoomIDForAlias(ctx, request.Alias)
if err != nil {
return err
}
/*
TODO: Why is this here? It creates an unnecessary dependency
from the roomserver to the appservice component, which should be
altogether optional.
if roomID == "" {
// No room found locally, try our application services by making a call to
// the appservice component
aliasReq := appserviceAPI.RoomAliasExistsRequest{Alias: request.Alias}
var aliasResp appserviceAPI.RoomAliasExistsResponse
if err = r.AppserviceAPI.RoomAliasExists(ctx, &aliasReq, &aliasResp); err != nil {
return err
}
if aliasResp.AliasExists {
roomID, err = r.DB.GetRoomIDForAlias(ctx, request.Alias)
if err != nil {
return err
}
}
}
*/
response.RoomID = roomID
return nil
}
// GetAliasesForRoomID implements alias.RoomserverInternalAPI
func (r *RoomserverInternalAPI) GetAliasesForRoomID(
ctx context.Context,
request *api.GetAliasesForRoomIDRequest,
response *api.GetAliasesForRoomIDResponse,
) error {
// Look up the aliases in the database for the given RoomID
aliases, err := r.DB.GetAliasesForRoomID(ctx, request.RoomID)
if err != nil {
return err
}
response.Aliases = aliases
return nil
}
// GetCreatorIDForAlias implements alias.RoomserverInternalAPI
func (r *RoomserverInternalAPI) GetCreatorIDForAlias(
ctx context.Context,
request *api.GetCreatorIDForAliasRequest,
response *api.GetCreatorIDForAliasResponse,
) error {
// Look up the aliases in the database for the given RoomID
creatorID, err := r.DB.GetCreatorIDForAlias(ctx, request.Alias)
if err != nil {
return err
}
response.UserID = creatorID
return nil
}
// RemoveRoomAlias implements alias.RoomserverInternalAPI
func (r *RoomserverInternalAPI) RemoveRoomAlias(
ctx context.Context,
request *api.RemoveRoomAliasRequest,
response *api.RemoveRoomAliasResponse,
) error {
// Look up the room ID in the database
roomID, err := r.DB.GetRoomIDForAlias(ctx, request.Alias)
if err != nil {
return err
}
// Remove the dalias from the database
if err := r.DB.RemoveRoomAlias(ctx, request.Alias); err != nil {
return err
}
// Send an updated m.room.aliases event
// At this point we've already committed the alias to the database so we
// shouldn't cancel this request.
// TODO: Ensure that we send unsent events when if server restarts.
return r.sendUpdatedAliasesEvent(context.TODO(), request.UserID, roomID)
}
type roomAliasesContent struct {
Aliases []string `json:"aliases"`
}
// Build the updated m.room.aliases event to send to the room after addition or
// removal of an alias
func (r *RoomserverInternalAPI) sendUpdatedAliasesEvent(
ctx context.Context, userID string, roomID string,
) error {
serverName := string(r.Cfg.Matrix.ServerName)
builder := gomatrixserverlib.EventBuilder{
Sender: userID,
RoomID: roomID,
Type: "m.room.aliases",
StateKey: &serverName,
}
// Retrieve the updated list of aliases, marhal it and set it as the
// event's content
aliases, err := r.DB.GetAliasesForRoomID(ctx, roomID)
if err != nil {
return err
}
content := roomAliasesContent{Aliases: aliases}
rawContent, err := json.Marshal(content)
if err != nil {
return err
}
err = builder.SetContent(json.RawMessage(rawContent))
if err != nil {
return err
}
// Get needed state events and depth
eventsNeeded, err := gomatrixserverlib.StateNeededForEventBuilder(&builder)
if err != nil {
return err
}
if len(eventsNeeded.Tuples()) == 0 {
return errors.New("expecting state tuples for event builder, got none")
}
req := api.QueryLatestEventsAndStateRequest{
RoomID: roomID,
StateToFetch: eventsNeeded.Tuples(),
}
var res api.QueryLatestEventsAndStateResponse
if err = r.QueryLatestEventsAndState(ctx, &req, &res); err != nil {
return err
}
builder.Depth = res.Depth
builder.PrevEvents = res.LatestEvents
// Add auth events
authEvents := gomatrixserverlib.NewAuthEvents(nil)
for i := range res.StateEvents {
err = authEvents.AddEvent(&res.StateEvents[i].Event)
if err != nil {
return err
}
}
refs, err := eventsNeeded.AuthEventReferences(&authEvents)
if err != nil {
return err
}
builder.AuthEvents = refs
roomInfo, err := r.DB.RoomInfo(ctx, roomID)
if err != nil {
return err
}
if roomInfo == nil {
return fmt.Errorf("room %s does not exist", roomID)
}
// Build the event
now := time.Now()
event, err := builder.Build(
now, r.Cfg.Matrix.ServerName, r.Cfg.Matrix.KeyID,
r.Cfg.Matrix.PrivateKey, roomInfo.RoomVersion,
)
if err != nil {
return err
}
// Create the request
ire := api.InputRoomEvent{
Kind: api.KindNew,
Event: event.Headered(roomInfo.RoomVersion),
AuthEventIDs: event.AuthEventIDs(),
SendAsServer: serverName,
}
inputReq := api.InputRoomEventsRequest{
InputRoomEvents: []api.InputRoomEvent{ire},
}
var inputRes api.InputRoomEventsResponse
// Send the request
r.InputRoomEvents(ctx, &inputReq, &inputRes)
return inputRes.Err()
}