Add basic encryption support for simple bots

.gitignore

@@ -1,5 +1,6 @@
 .idea/
 lib/
+examples/storage/
 
 # Logs
 logs

examples/encryption_bot.ts

@@ -0,0 +1,104 @@
+import {
+    EncryptionAlgorithm,
+    FileMessageEventContent,
+    LogLevel,
+    LogService,
+    MatrixClient, MessageEvent,
+    RichConsoleLogger,
+    SimpleFsStorageProvider,
+} from "../src";
+import { SqliteCryptoStorageProvider } from "../src/storage/SqliteCryptoStorageProvider";
+import * as fs from "fs";
+
+LogService.setLogger(new RichConsoleLogger());
+LogService.setLevel(LogLevel.TRACE);
+LogService.muteModule("Metrics");
+LogService.trace = LogService.debug;
+
+let creds = null;
+try {
+    creds = require("../../examples/storage/encryption_bot.creds.json");
+} catch (e) {
+    // ignore
+}
+
+const dmTarget = creds?.['dmTarget'] ?? "@admin:localhost";
+const homeserverUrl = creds?.['homeserverUrl'] ?? "http://localhost:8008";
+const accessToken = creds?.['accessToken'] ?? 'YOUR_TOKEN';
+const storage = new SimpleFsStorageProvider("./examples/storage/encryption_bot.json");
+const crypto = new SqliteCryptoStorageProvider("./examples/storage/encryption_bot.db");
+const worksImage = fs.readFileSync("./examples/static/it-works.png");
+
+const client = new MatrixClient(homeserverUrl, accessToken, storage, crypto);
+
+(async function() {
+    let encryptedRoomId: string;
+    const joinedRooms = await client.getJoinedRooms();
+    await client.crypto.prepare(joinedRooms); // init crypto because we're doing things before the client is started
+    for (const roomId of joinedRooms) {
+        if (await client.crypto.isRoomEncrypted(roomId)) {
+            encryptedRoomId = roomId;
+            break;
+        }
+    }
+    if (!encryptedRoomId) {
+        encryptedRoomId = await client.createRoom({
+            invite: [dmTarget],
+            is_direct: true,
+            visibility: "private",
+            preset: "trusted_private_chat",
+            initial_state: [
+                {type: "m.room.encryption", state_key: "", content: {algorithm: EncryptionAlgorithm.MegolmV1AesSha2}},
+                {type: "m.room.guest_access", state_key: "", content: {guest_access: "can_join"}},
+            ],
+        });
+    }
+
+    client.on("room.failed_decryption", async (roomId: string, event: any, e: Error) => {
+        LogService.error("index", `Failed to decrypt ${roomId} ${event['event_id']} because `, e);
+    });
+
+    client.on("room.message", async (roomId: string, event: any) => {
+        if (roomId !== encryptedRoomId) return;
+
+        const message = new MessageEvent(event);
+
+        if (message.sender === (await client.getUserId()) && message.messageType === "m.notice") {
+            // yay, we decrypted our own message. Communicate that back for testing purposes.
+            const encrypted = await client.crypto.encryptMedia(Buffer.from(worksImage));
+            const mxc = await client.uploadContent(encrypted.buffer);
+            await client.sendMessage(roomId, {
+                msgtype: "m.image",
+                body: "it-works.png",
+                info: {
+                    // XXX: We know these details, so have hardcoded them.
+                    w: 256,
+                    h: 256,
+                    mimetype: "image/png",
+                    size: worksImage.length,
+                },
+                file: {
+                    url: mxc,
+                    ...encrypted.file,
+                },
+            });
+            return;
+        }
+
+        if (message.messageType === "m.image") {
+            const fileEvent = new MessageEvent<FileMessageEventContent>(message.raw);
+            const decrypted = await client.crypto.decryptMedia(fileEvent.content.file);
+            fs.writeFileSync('./examples/storage/decrypted.png', decrypted);
+            await client.unstableApis.addReactionToEvent(roomId, fileEvent.eventId, 'Decrypted');
+            return;
+        }
+
+        if (message.messageType !== "m.text") return;
+        if (message.textBody.startsWith("!ping")) {
+            await client.replyNotice(roomId, event, "Pong");
+        }
+    });
+
+    LogService.info("index", "Starting bot...");
+    await client.start();
+})();

package.json

@@ -20,7 +20,8 @@
     "test": "ts-mocha --project ./tsconfig.json test/*Test.ts test/**/*.ts",
     "build:examples": "tsc -p tsconfig-examples.json",
     "example:appservice": "yarn build:examples && node lib/examples/appservice.js",
-    "example:login_register": "yarn build:examples && node lib/examples/login_register.js"
+    "example:login_register": "yarn build:examples && node lib/examples/login_register.js",
+    "example:encryption_bot": "yarn build:examples && node lib/examples/encryption_bot.js"
   },
   "main": "./lib/index.js",
   "typings": "./lib/index.d.ts",
@@ -47,8 +48,13 @@
     "scripts/*",
     "tsconfig.json"
   ],
+  "optionalDependencies": {
+    "better-sqlite3": "^7.4.3"
+  },
   "dependencies": {
+    "@matrix-org/olm": "https://gitlab.matrix.org/api/v4/projects/27/packages/npm/@matrix-org/olm/-/@matrix-org/olm-3.2.4.tgz",
     "@types/express": "^4.17.7",
+    "another-json": "^0.2.0",
     "chalk": "^4.1.0",
     "express": "^4.17.1",
     "glob-to-regexp": "^0.4.1",
@@ -64,9 +70,11 @@
     "sanitize-html": "^2.3.2"
   },
   "devDependencies": {
+    "@types/better-sqlite3": "^5.4.3",
     "@types/expect": "^24.3.0",
     "@types/mocha": "^8.0.1",
     "@types/node": "10",
+    "@types/simple-mock": "^0.8.2",
     "@typescript-eslint/eslint-plugin": "^3.8.0",
     "@typescript-eslint/eslint-plugin-tslint": "^3.8.0",
     "@typescript-eslint/parser": "^3.8.0",
@@ -81,6 +89,6 @@
     "tmp": "^0.2.1",
     "ts-mocha": "^7.0.0",
     "tslint": "^6.1.3",
-    "typescript": "^3.9.7"
+    "typescript": "^4.3.5"
   }
 }