successfully forwarding blockchain events to matrix

backend/.env.example

@@ -1,6 +1,11 @@
-PORT=3000
-DATA_DIR="./data"
+API_LISTEN_PORT=3000
+LEVEL_DATA_DIR="./data"
 SEMANTIC_SCHOLAR_API_KEY=
 ETH_NETWORK="localhost"
 ETH_PRIVATE_KEY=
-INFURA_API_KEY=
+INFURA_API_KEY=
+MATRIX_HOMESERVER_URL="https://matrix.dgov.io"
+MATRIX_USER="forum-api"
+MATRIX_PASSWORD=
+BOT_STORAGE_PATH="./data/bot-storage.json"
+BOT_CRYPTO_STORAGE_PATH="./data/bot-crypto"

backend/.gitignore

@@ -1,3 +1,4 @@
 node_modules/
 .env
-data/
+data/
+registration.yaml

backend/README.md

@@ -0,0 +1,17 @@
+# Setup
+
+1.
+
+    cp .env.example .env
+
+1.
+
+    npm install
+
+1.
+
+    npm run registration
+
+1.
+
+    docker compose up -d --build

backend/docker-compose.yaml

@@ -7,4 +7,6 @@ services:
     volumes:
       - ./data:/data
     environment:
-      - DATA_DIR=/data
+      - LEVEL_DATA_DIR=/data
+      - BOT_STORAGE_PATH="./data/bot-storage.json"
+      - BOT_CRYPTO_STORAGE_PATH="./data/bot-crypto"

backend/package.json

@@ -16,7 +16,9 @@
     "ethers": "^6.12.0",
     "express": "^4.18.2",
     "express-async-errors": "^3.1.1",
+    "fastq": "^1.17.1",
     "level": "^8.0.1",
+    "matrix-bot-sdk": "^0.7.1",
     "object-hash": "^3.0.0"
   },
   "devDependencies": {

backend/src/api.js

@@ -0,0 +1,46 @@
+const express = require('express');
+
+require('express-async-errors');
+
+const read = require('./read');
+const write = require('./write');
+const importFromSS = require('./import-from-ss');
+
+const app = express();
+const port = process.env.API_LISTEN_PORT || 3000;
+
+app.use(express.json());
+
+app.post('/write', write);
+
+app.get('/read/:hash', async (req, res) => {
+  const { hash } = req.params;
+  console.log('read', hash);
+  const data = await read(hash);
+  res.json(data);
+});
+
+app.post('/importFromSemanticScholar', importFromSS);
+
+app.get('*', (req, res) => {
+  console.log(`404 req.path: ${req.path}`);
+  res.status(404).json({ errorCode: 404 });
+});
+
+app.use((err, req, res, next) => {
+  const status = err.response?.status ?? err.status ?? 500;
+  const message = err.response?.data?.error ?? err.message;
+  console.error(`error: ${message}`, err);
+  res.status(status).send(message);
+  next();
+});
+
+const start = () => {
+  app.listen(port, () => {
+    console.log(`Listening on port ${port}`);
+  });
+};
+
+module.exports = {
+  start,
+};

backend/src/contracts.js

@@ -2,6 +2,7 @@ const ethers = require('ethers');
 
 const { getContractAddressByNetworkName } = require('./contract-config');
 const DAOArtifact = require('../contractArtifacts/DAO.json');
+const ProposalsArtifact = require('../contractArtifacts/Proposals.json');
 
 const network = process.env.ETH_NETWORK;
 
@@ -23,12 +24,15 @@ const getProvider = () => {
 
 const wallet = new ethers.Wallet(process.env.ETH_PRIVATE_KEY, getProvider());
 
-const getContract = (name) => new ethers.Contract(
-  getContractAddressByNetworkName(process.env.ETH_NETWORK, name),
-  DAOArtifact.abi,
-  wallet,
-);
-
 module.exports = {
-  dao: getContract('DAO'),
+  dao: new ethers.Contract(
+    getContractAddressByNetworkName(process.env.ETH_NETWORK, 'DAO'),
+    DAOArtifact.abi,
+    wallet,
+  ),
+  proposals: new ethers.Contract(
+    getContractAddressByNetworkName(process.env.ETH_NETWORK, 'Proposals'),
+    ProposalsArtifact.abi,
+    wallet,
+  ),
 };

backend/src/db.js

@@ -1,6 +1,6 @@
 const { Level } = require('level');
 
-const dataDir = process.env.DATA_DIR || 'data';
+const dataDir = process.env.LEVEL_DATA_DIR || 'data';
 
 module.exports = {
   forum: new Level(`${dataDir}/forum`, { valueEncoding: 'json' }),

backend/src/import-from-ss.js

@@ -212,4 +212,6 @@ module.exports = async (req, res) => {
   } else {
     res.status(400).end();
   }
+
+  // TODO: Send matrix room event on SS import
 };

backend/src/index.js

@@ -1,40 +1,5 @@
-const express = require('express');
-
-const read = require('./read');
-const write = require('./write');
-const importFromSS = require('./import-from-ss');
-
 require('dotenv').config();
-require('express-async-errors');
 
-const app = express();
-const port = process.env.PORT || 3000;
-
-app.use(express.json());
-
-app.post('/write', write);
-app.get('/read/:hash', read);
-app.post('/importFromSemanticScholar', importFromSS);
-
-app.get('*', (req, res) => {
-  console.log(`404 req.path: ${req.path}`);
-  res.status(404).json({ errorCode: 404 });
-});
-
-app.use((err, req, res, next) => {
-  const status = err.response?.status ?? 500;
-  const message = err.response?.data?.error ?? err.message;
-  console.error(`error: ${message}`, err);
-  res.status(status).send(message);
-  next();
-});
-
-app.listen(port, () => {
-  console.log(`Listening on port ${port}`);
-});
-
-// TODO: Subscribe to contract events
-
-// TODO: Send matrix room events for proposal events
-
-// TODO: Send matrix room event on SS import
+require('./api').start();
+require('./matrix').start();
+require('./proposals').start();

backend/src/matrix.js

@@ -0,0 +1,76 @@
+const {
+  AutojoinRoomsMixin,
+  MatrixAuth,
+  MatrixClient,
+  RustSdkCryptoStorageProvider,
+  SimpleFsStorageProvider,
+} = require('matrix-bot-sdk');
+const fastq = require('fastq');
+
+const {
+  MATRIX_HOMESERVER_URL,
+  MATRIX_USER,
+  MATRIX_PASSWORD,
+  BOT_STORAGE_PATH,
+  BOT_CRYPTO_STORAGE_PATH,
+} = process.env;
+
+const storageProvider = new SimpleFsStorageProvider(BOT_STORAGE_PATH);
+const cryptoProvider = new RustSdkCryptoStorageProvider(BOT_CRYPTO_STORAGE_PATH);
+let client;
+let joinedRooms;
+const processOutboundQueue = async ({ text }) => {
+  joinedRooms.forEach(async (roomId) => {
+    await client.sendText(roomId, text);
+  });
+};
+const outboundQueue = fastq(processOutboundQueue, 1);
+outboundQueue.pause();
+
+const start = async () => {
+  console.log('MATRIX_HOMESERVER_URL:', MATRIX_HOMESERVER_URL);
+  const auth = new MatrixAuth(MATRIX_HOMESERVER_URL);
+  const authClient = await auth.passwordLogin(MATRIX_USER, MATRIX_PASSWORD);
+  client = new MatrixClient(
+    MATRIX_HOMESERVER_URL,
+    authClient.accessToken,
+    storageProvider,
+    cryptoProvider,
+  );
+
+  // Automatically join a room to which we are invited
+  AutojoinRoomsMixin.setupOnClient(client);
+
+  joinedRooms = await client.getJoinedRooms();
+  console.log('joined rooms:', joinedRooms);
+
+  async function handleCommand(roomId, event) {
+    // Don't handle unhelpful events (ones that aren't text messages, are redacted, or sent by us)
+    if (event.content?.msgtype !== 'm.text') return;
+    if (event.sender === await client.getUserId()) return;
+
+    // Check to ensure that the `!hello` command is being run
+    const { body } = event.content;
+    if (!body?.startsWith('!hello')) return;
+
+    // Now that we've passed all the checks, we can actually act upon the command
+    await client.replyNotice(roomId, event, 'Hello world!');
+  }
+
+  // Before we start the bot, register our command handler
+  client.on('room.message', handleCommand);
+
+  client.start().then(() => {
+    console.log('Bot started!');
+    outboundQueue.resume();
+  });
+};
+
+const broadcastMessage = (text) => {
+  outboundQueue.push({ text });
+};
+
+module.exports = {
+  start,
+  broadcastMessage,
+};

backend/src/proposals.js

@@ -0,0 +1,29 @@
+const { proposals } = require('./contracts');
+const read = require('./read');
+const { broadcastMessage } = require('./matrix');
+
+// Subscribe to proposal events
+const start = () => {
+  proposals.on('NewProposal', async (proposalIndex) => {
+    // TODO: Cache these in leveldb so we know when we've already seen one and sent to matrix
+    console.log('New Proposal, index', proposalIndex);
+
+    const proposal = await proposals.proposals(proposalIndex);
+    console.log('postId:', proposal.postId);
+
+    // Read post from database
+    const post = await read(proposal.postId);
+    console.log('post.content:', post.content);
+
+    // Send matrix room event
+    let message = `Proposal ${proposalIndex}\n\n${post.content}`;
+    if (post.embeddedData && Object.entries(post.embeddedData).length) {
+      message += `\n\n${JSON.stringify(post.embeddedData, null, 2)}`;
+    }
+    broadcastMessage(message);
+  });
+};
+
+module.exports = {
+  start,
+};

backend/src/read.js

@@ -3,24 +3,14 @@ const objectHash = require('object-hash');
 const verifySignature = require('./verify-signature');
 const { forum } = require('./db');
 
-module.exports = async (req, res) => {
-  const { hash } = req.params;
-  console.log('read', hash);
-
+const read = async (hash) => {
   // Fetch content
-  let data;
-  try {
-    data = await forum.get(req.params.hash);
-  } catch (e) {
-    console.log('read error:', e.message, hash);
-    res.status(e.status).end();
-    return;
-  }
+  const data = await forum.get(hash);
 
   data.embeddedData = data.embeddedData || undefined;
 
   const {
-    authors, content, signature, embeddedData,
+    authors, content, signature, embeddedData, citations,
   } = data;
 
   // Verify hash
@@ -28,18 +18,17 @@ module.exports = async (req, res) => {
     authors, content, signature, embeddedData,
   });
   if (derivedHash !== hash) {
-    console.log('error: hash mismatch');
-    res.status(500).end();
-    return;
+    throw new Error('hash mismatch');
   }
 
   // Verify signature
   if (!verifySignature(data)) {
-    console.log('error: signature verificaition failed');
-    res.status(500).end();
-    return;
+    throw new Error('signature verificaition failed');
   }
 
-  // Return content
-  res.json(data);
+  return {
+    authors, content, signature, embeddedData, citations,
+  };
 };
+
+module.exports = read;