Refactor how we listen for matrix events. (#446)

* Refactor Matrix event listener in Mjolnir and ManagedMjolnir.

closes #411.

Issue #411 says that we have to be careful about room.join,
but this was before we figured how to make matrix-appservice-bridge
echo events sent by its own intents.

* Remove MatrixClientListener since it isn't actually needed.

* Protect which config values can be used for ManagedMjolnirs.

* Introduce MatrixSendClient

so listeners aren't accidentally added to a MatrixClient instead
of MatrixEmitter.

* doc

* Move provisioned mjolnir config to src/config.

This just aids maintance so whenever someone goes to change the config
of the bot they will see this and update it.

* doc for matrix intent listener.

Author: Gnuxie

src/ManagementRoomOutput.ts

@@ -15,8 +15,9 @@ limitations under the License.
 */
 
 import * as Sentry from "@sentry/node";
-import { extractRequestError, LogLevel, LogService, MatrixClient, MessageType, Permalinks, TextualMessageEventContent, UserID } from "matrix-bot-sdk";
+import { extractRequestError, LogLevel, LogService, MessageType, Permalinks, TextualMessageEventContent, UserID } from "matrix-bot-sdk";
 import { IConfig } from "./config";
+import { MatrixSendClient } from "./MatrixEmitter";
 import { htmlEscape } from "./utils";
 
 const levelToFn = {
@@ -33,7 +34,7 @@ export default class ManagementRoomOutput {
 
     constructor(
         private readonly managementRoomId: string,
-        private readonly client: MatrixClient,
+        private readonly client: MatrixSendClient,
         private readonly config: IConfig,
     ) {
 

src/MatrixEmitter.ts

@@ -0,0 +1,55 @@
+/*
+Copyright 2019-2022 The Matrix.org Foundation C.I.C.
+
+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.
+*/
+
+import EventEmitter from "events";
+import { MatrixClient } from "matrix-bot-sdk";
+
+/**
+ * This is an interface created in order to keep the event listener
+ * Mjolnir uses for new events generic.
+ * Used to provide a unified API for messages received from matrix-bot-sdk (using GET /sync)
+ * when we're in single bot mode and messages received from matrix-appservice-bridge (using pushed /transaction)
+ * when we're in appservice mode.
+ */
+export declare interface MatrixEmitter extends EventEmitter {
+    on(event: 'room.event', listener: (roomId: string, mxEvent: any) => void ): this
+    emit(event: 'room.event', roomId: string, mxEvent: any): boolean
+
+    on(event: 'room.message', listener: (roomId: string, mxEvent: any) => void ): this
+    emit(event: 'room.message', roomId: string, mxEvent: any): boolean
+
+    on(event: 'room.invite', listener: (roomId: string, mxEvent: any) => void ): this
+    emit(event: 'room.invite', roomId: string, mxEvent: any): boolean
+
+    on(event: 'room.join', listener: (roomId: string, mxEvent: any) => void ): this
+    emit(event: 'room.join', roomId: string, mxEvent: any): boolean
+
+    on(event: 'room.leave', listener: (roomId: string, mxEvent: any) => void ): this
+    emit(event: 'room.leave', roomId: string, mxEvent: any): boolean
+
+    on(event: 'room.archived', listener: (roomId: string, mxEvent: any) => void ): this
+    emit(event: 'room.archived', roomId: string, mxEvent: any): boolean
+
+    start(): Promise<void>;
+    stop(): void;
+}
+
+/**
+ * A `MatrixClient` without the properties of `MatrixEmitter`.
+ * This is in order to enforce listeners are added to `MatrixEmitter`s
+ * rather than on the matrix-bot-sdk version of the matrix client.
+ */
+export type MatrixSendClient = Omit<MatrixClient, keyof MatrixEmitter>;

src/Mjolnir.ts

@@ -18,7 +18,6 @@ import {
     extractRequestError,
     LogLevel,
     LogService,
-    MatrixClient,
     MembershipEvent,
     Permalinks,
 } from "matrix-bot-sdk";
@@ -39,6 +38,7 @@ import ManagementRoomOutput from "./ManagementRoomOutput";
 import { ProtectionManager } from "./protections/ProtectionManager";
 import { RoomMemberManager } from "./RoomMembers";
 import ProtectedRoomsConfig from "./ProtectedRoomsConfig";
+import { MatrixEmitter, MatrixSendClient } from "./MatrixEmitter";
 
 export const STATE_NOT_STARTED = "not_started";
 export const STATE_CHECKING_PERMISSIONS = "checking_permissions";
@@ -88,15 +88,15 @@ export class Mjolnir {
 
     /**
      * Adds a listener to the client that will automatically accept invitations.
-     * @param {MatrixClient} client
+     * @param {MatrixSendClient} client
      * @param options By default accepts invites from anyone.
      * @param {string} options.managementRoom The room to report ignored invitations to if `recordIgnoredInvites` is true.
      * @param {boolean} options.recordIgnoredInvites Whether to report invites that will be ignored to the `managementRoom`.
      * @param {boolean} options.autojoinOnlyIfManager Whether to only accept an invitation by a user present in the `managementRoom`.
      * @param {string} options.acceptInvitesFromSpace A space of users to accept invites from, ignores invites form users not in this space.
      */
-    private static addJoinOnInviteListener(mjolnir: Mjolnir, client: MatrixClient, options: { [key: string]: any }) {
-        client.on("room.invite", async (roomId: string, inviteEvent: any) => {
+    private static addJoinOnInviteListener(mjolnir: Mjolnir, client: MatrixSendClient, options: { [key: string]: any }) {
+        mjolnir.matrixEmitter.on("room.invite", async (roomId: string, inviteEvent: any) => {
             const membershipEvent = new MembershipEvent(inviteEvent);
 
             const reportInvite = async () => {
@@ -130,17 +130,16 @@ export class Mjolnir {
                     });
                 if (!spaceUserIds.includes(membershipEvent.sender)) return reportInvite(); // ignore invite
             }
-
             return client.joinRoom(roomId);
         });
     }
 
     /**
      * Create a new Mjolnir instance from a client and the options in the configuration file, ready to be started.
-     * @param {MatrixClient} client The client for Mjolnir to use.
+     * @param {MatrixSendClient} client The client for Mjolnir to use.
      * @returns A new Mjolnir instance that can be started without further setup.
      */
-    static async setupMjolnirFromConfig(client: MatrixClient, config: IConfig): Promise<Mjolnir> {
+    static async setupMjolnirFromConfig(client: MatrixSendClient, matrixEmitter: MatrixEmitter, config: IConfig): Promise<Mjolnir> {
         const policyLists: PolicyList[] = [];
         const joinedRooms = await client.getJoinedRooms();
 
@@ -152,15 +151,16 @@ export class Mjolnir {
         }
 
         const ruleServer = config.web.ruleServer ? new RuleServer() : null;
-        const mjolnir = new Mjolnir(client, await client.getUserId(), managementRoomId, config, policyLists, ruleServer);
+        const mjolnir = new Mjolnir(client, await client.getUserId(), matrixEmitter, managementRoomId, config, policyLists, ruleServer);
         await mjolnir.managementRoomOutput.logMessage(LogLevel.INFO, "index", "Mjolnir is starting up. Use !mjolnir to query status.");
         Mjolnir.addJoinOnInviteListener(mjolnir, client, config);
         return mjolnir;
     }
 
     constructor(
-        public readonly client: MatrixClient,
+        public readonly client: MatrixSendClient,
         private readonly clientUserId: string,
+        public readonly matrixEmitter: MatrixEmitter,
         public readonly managementRoomId: string,
         public readonly config: IConfig,
         private policyLists: PolicyList[],
@@ -171,9 +171,9 @@ export class Mjolnir {
 
         // Setup bot.
 
-        client.on("room.event", this.handleEvent.bind(this));
+        matrixEmitter.on("room.event", this.handleEvent.bind(this));
 
-        client.on("room.message", async (roomId, event) => {
+        matrixEmitter.on("room.message", async (roomId, event) => {
             if (roomId !== this.managementRoomId) return;
             if (!event['content']) return;
 
@@ -208,11 +208,11 @@ export class Mjolnir {
             }
         });
 
-        client.on("room.join", (roomId: string, event: any) => {
+        matrixEmitter.on("room.join", (roomId: string, event: any) => {
             LogService.info("Mjolnir", `Joined ${roomId}`);
             return this.resyncJoinedRooms();
         });
-        client.on("room.leave", (roomId: string, event: any) => {
+        matrixEmitter.on("room.leave", (roomId: string, event: any) => {
             LogService.info("Mjolnir", `Left ${roomId}`);
             return this.resyncJoinedRooms();
         });
@@ -234,7 +234,7 @@ export class Mjolnir {
             this.reportPoller = new ReportPoller(this, this.reportManager);
         }
         // Setup join/leave listener
-        this.roomJoins = new RoomMemberManager(this.client);
+        this.roomJoins = new RoomMemberManager(this.matrixEmitter);
         this.taskQueue = new ThrottlingQueue(this, config.backgroundDelayMS);
 
         this.protectionManager = new ProtectionManager(this);
@@ -303,7 +303,7 @@ export class Mjolnir {
             }
 
             // Start the bot.
-            await this.client.start();
+            await this.matrixEmitter.start();
 
             this.currentState = STATE_SYNCING;
             if (this.config.syncOnStartup) {
@@ -331,7 +331,7 @@ export class Mjolnir {
      */
     public stop() {
         LogService.info("Mjolnir", "Stopping Mjolnir...");
-        this.client.stop();
+        this.matrixEmitter.stop();
         this.webapis.stop();
         this.reportPoller?.stop();
     }

src/ProtectedRoomsConfig.ts

@@ -15,8 +15,9 @@ limitations under the License.
 */
 
 import AwaitLock from 'await-lock';
-import { extractRequestError, LogService, MatrixClient, Permalinks } from "matrix-bot-sdk";
+import { extractRequestError, LogService, Permalinks } from "matrix-bot-sdk";
 import { IConfig } from "./config";
+import { MatrixSendClient } from './MatrixEmitter';
 const PROTECTED_ROOMS_EVENT_TYPE = "org.matrix.mjolnir.protected_rooms";
 
 /**
@@ -32,7 +33,7 @@ export default class ProtectedRoomsConfig {
     /** This is to prevent clobbering the account data for the protected rooms if several rooms are explicitly protected concurrently. */
     private accountDataLock = new AwaitLock();
 
-    constructor(private readonly client: MatrixClient) {
+    constructor(private readonly client: MatrixSendClient) {
 
     }
 

src/ProtectedRoomsSet.ts

@@ -14,10 +14,11 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-import { LogLevel, LogService, MatrixClient, MatrixGlob, Permalinks, UserID } from "matrix-bot-sdk";
+import { LogLevel, LogService, MatrixGlob, Permalinks, UserID } from "matrix-bot-sdk";
 import { IConfig } from "./config";
 import ErrorCache, { ERROR_KIND_FATAL, ERROR_KIND_PERMISSION } from "./ErrorCache";
 import ManagementRoomOutput from "./ManagementRoomOutput";
+import { MatrixSendClient } from "./MatrixEmitter";
 import AccessControlUnit, { Access } from "./models/AccessControlUnit";
 import { RULE_ROOM, RULE_SERVER, RULE_USER } from "./models/ListRule";
 import PolicyList, { ListRuleChange } from "./models/PolicyList";
@@ -88,7 +89,7 @@ export class ProtectedRoomsSet {
     private readonly accessControlUnit = new AccessControlUnit([]);
 
     constructor(
-        private readonly client: MatrixClient,
+        private readonly client: MatrixSendClient,
         private readonly clientUserId: string,
         private readonly managementRoomId: string,
         private readonly managementRoomOutput: ManagementRoomOutput,

src/RoomMembers.ts

@@ -1,4 +1,4 @@
-import { MatrixClient } from "matrix-bot-sdk";
+import { MatrixEmitter } from "./MatrixEmitter";
 
 enum Action {
     Join,
@@ -154,7 +154,7 @@ class RoomMembers {
 export class RoomMemberManager {
     private perRoom: Map<string /* room id */, RoomMembers> = new Map();
     private readonly cbHandleEvent;
-    constructor(private client: MatrixClient) {
+    constructor(private client: MatrixEmitter) {
         // Listen for join events.
         this.cbHandleEvent = this.handleEvent.bind(this);
         client.on("room.event", this.cbHandleEvent);