1.2.0

.gitignore

@@ -1,2 +1,2 @@
-config.js
+/config.js
 node_modules/

LICENSE

@@ -0,0 +1,19 @@
+Copyright (c) 2023 Râu Cao
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

@@ -0,0 +1,56 @@
+# XMPP Lightning Anti-Spam
+
+In order to combat spam in public chat rooms, they can be configured so that
+new, unknown participants have to request voice before being able to write
+messages (known as a "moderated channel").
+
+This bot listens to those voice requests, and when it sees one, it sends a
+direct message to the user, which offers to give them voice immediately, in
+exchange for a small amount of sats[^1], payable via the Lightning Network[^2].
+
+## Requirements
+
+* [Node.js](https://nodejs.org) and [NPM](https://www.npmjs.com)
+* An XMPP account, which has admin permissions for the channels you want it to
+  manage voice requests in
+* A hosted Lightning Network account compatible with LndHub clients (e.g. a
+  [Kosmos](https://kosmos.org) or [Alby](https://getalby.com/)
+  account, or self-hosted with
+  [lndhub.go](https://github.com/getAlby/lndhub.go)).
+
+## Setup
+
+Clone this repository:
+
+    git clone https://gitea.kosmos.org/raucao/xmpp-lightning-antispam.git
+
+Install required dependencies:
+
+    npm install
+
+Create a config file from the included sample:
+
+    cp samples/config.js config.js
+
+Edit the config file using your favorite editor:
+
+    vim config.js
+
+Start the program:
+
+    npm start
+
+## Deployment
+
+Set up as described above, or use a cloud platform instead.
+
+An example for a systemd service can be found in
+`samples/xmpp-lightning-antispam.service`.
+
+## Contact
+
+E-Mail, Chat, Social, Lightning: raucao@kosmos.org
+
+[^1]: Sats are the smallest unit of bitcoin (1 sat = 0.00000001 BTC)
+[^2]: The Lightning Network is a peer-to-peer network for instantly and very
+      cheaply sending and receiving bitcoin directly between nodes

index.js

@@ -42,16 +42,24 @@ function startPingInterval () {
 }
 
 function waitForInvoicePaid (room, nick, invoice, retries=0) {
+  let timeout = 3000;
+
   if (retries >= 300) {
     console.log(`Invoice not paid after 15 minutes: ${invoice.payment_hash}`);
-    return false;
+    let timeout = 5000;
+    if (retries >= 500) {
+      // TODO ask user to request voice again to create a new invoice
+      return false;
+    }
   }
+
   lndhub.getInvoice(invoice.payment_hash).then(async data => {
-    if (data.is_paid) {
+    if (data && data.is_paid) {
       console.log(`Invoice paid: ${invoice.payment_hash}`);
       await grantVoice(room, nick);
     } else {
-      setTimeout(waitForInvoicePaid, 3000, room, nick, invoice, retries++);
+      if (!data) console.warn('Fetching invoice status failed');
+      setTimeout(waitForInvoicePaid, timeout, room, nick, invoice, retries++);
     }
   });
 }
@@ -85,10 +93,14 @@ async function handleVoiceRequest (stanza) {
     console.log(`${nick} requested voice in ${room}`);
 
     const invoice = await lndhub.createInvoice(config.amounts.voice, `Donation for ${room}`);
-    console.log(`Created lightning invoice for ${nick}: ${invoice.payment_hash}`)
-
-    await respondToVoiceRequest(room, nick, invoice);
-    waitForInvoicePaid(room, nick, invoice);
+    if (invoice) {
+      console.log(`Created lightning invoice for ${nick}: ${invoice.payment_hash}`)
+      await respondToVoiceRequest(room, nick, invoice);
+      waitForInvoicePaid(room, nick, invoice);
+    } else {
+      console.warn(`Invoice creation failed!`);
+      // TODO notify ops contact
+    }
   } catch(err) {
     console.error(err);
   }
@@ -105,10 +117,16 @@ async function connectXmpp () {
 }
 
 function connectLndhub () {
-  return lndhub.auth(config.lndhub.username, config.lndhub.password).then(() => {
-    console.log("Connected to Lndhub");
+  return lndhub.auth(config.lndhub.username, config.lndhub.password).then(connected => {
+    if (connected) {
+      console.log("Connected to Lndhub");
+      // automatically refresh auth token once a day
+      setInterval(() => lndhub.reauth(), 86400000);
+    } else {
+      process.exit(1);
+    }
   }).catch(err => {
-    console.warn(`Lndhub auth failed: ${err}`);
+    console.error(`Lndhub connection failed: ${err}`);
   });
 }
 

lib/lndhub.js

@@ -5,61 +5,82 @@ export default class Lndhub {
     this.baseUrl = baseUrl;
   }
 
+  async callEndpoint (method, path, payload) {
+    const options = { method, headers: { 'Content-Type': 'application/json' } };
+
+    if (path !== '/auth') {
+      options.headers['Authorization'] = `Bearer ${this.accessToken}`;
+    }
+    if (typeof payload !== 'undefined') {
+      options.body = JSON.stringify(payload);
+    }
+
+    const res = await fetch(`${this.baseUrl}${path}`, options);
+    return res.json();
+  }
+
+  async handleErroredRequest (result, retryFunction, args=[]) {
+    console.warn('API request failed:', result.message);
+    if (result.code === 1) {
+      return this.reauth().then(connected => {
+        if (connected) {
+          console.warn('Lndhub reconnected, trying again...');
+          return this[retryFunction](...args);
+        }
+      });
+    } else {
+      return false;
+    }
+  }
+
   async auth (username, password) {
     const payload = { "login": username, "password": password };
+    const data = await this.callEndpoint('post', '/auth', payload);
 
-    const res = await fetch(`${this.baseUrl}/auth`, {
-      method: 'post',
-      body: JSON.stringify(payload),
-      headers: { 'Content-Type': 'application/json' }
-    });
-    const data = await res.json();
-
-    this.refreshToken = data.refresh_token;
-    this.accessToken = data.access_token;
+    if (data.error) {
+      console.warn('Lndhub connection failed:', data.message);
+      return false;
+    } else {
+      this.refreshToken = data.refresh_token;
+      this.accessToken = data.access_token;
+      return true;
+    }
   }
 
   async reauth (refreshToken) {
     const payload = { "refresh_token": this.refreshToken };
+    const data = await this.callEndpoint('post', '/auth', payload);
 
-    const res = await fetch(`${this.baseUrl}/auth`, {
-      method: 'post',
-      body: JSON.stringify(payload),
-      headers: { 'Content-Type': 'application/json' }
-    });
-    const data = await res.json();
-
-    this.accessToken = data.access_token;
+    if (data.error) {
+      console.warn('Lndhub re-auth failed:', data.message);
+      return false;
+    } else {
+      if (this.accessToken !== data.access_token) {
+        console.log('Lndhub access token refreshed');
+      }
+      this.accessToken = data.access_token;
+      return true;
+    }
   }
 
   async createInvoice (amount, description) {
     const payload = { amount, description };
+    let data = await this.callEndpoint('post', '/v2/invoices', payload);
 
-    const res = await fetch(`${this.baseUrl}/v2/invoices`, {
-      method: 'post',
-      body: JSON.stringify(payload),
-      headers: {
-        'Content-Type': 'application/json',
-        'Authorization': `Bearer ${this.accessToken}`
-      }
-    });
-    const data = await res.json();
-    // TODO re-auth if token has expired
-
-    return data;
+    if (data.error) {
+      return this.handleErroredRequest(data, 'createInvoice', Array.from(arguments));
+    } else {
+      return data;
+    }
   }
 
   async getInvoice (paymentHash) {
-    const res = await fetch(`${this.baseUrl}/v2/invoices/${paymentHash}`, {
-      method: 'get',
-      headers: {
-        'Content-Type': 'application/json',
-        'Authorization': `Bearer ${this.accessToken}`
-      }
-    });
-    const data = await res.json();
-    // TODO re-auth if token has expired
+    const data = await this.callEndpoint('get', `/v2/invoices/${paymentHash}`);
 
-    return data;
+    if (data.error) {
+      return this.handleErroredRequest(data, 'getInvoice', Array.from(arguments));
+    } else {
+      return data;
+    }
   }
 }

package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "xmpp-lightning-antispam",
-  "version": "1.0.0",
+  "version": "1.2.0",
   "lockfileVersion": 2,
   "requires": true,
   "packages": {
     "": {
       "name": "xmpp-lightning-antispam",
-      "version": "1.0.0",
+      "version": "1.2.0",
       "license": "MIT",
       "dependencies": {
         "@xmpp/client": "^0.13.1",
@@ -941,12 +941,12 @@
       }
     },
     "node_modules/braces": {
-      "version": "3.0.2",
-      "resolved": "https://registry.npmjs.org/braces/-/braces-3.0.2.tgz",
-      "integrity": "sha512-b8um+L1RzM3WDSzvhm6gIz1yfTbBt6YTlcEKAvsmqCZZFw46z626lVj9j1yEPW33H5H+lBQpZMP1k8l+78Ha0A==",
+      "version": "3.0.3",
+      "resolved": "https://registry.npmjs.org/braces/-/braces-3.0.3.tgz",
+      "integrity": "sha512-yQbXgO/OSZVD2IsiLlro+7Hf6Q18EJrKSEsdoMzKePKXct3gvD8oLcOQdIzGupr5Fj+EDe8gO/lxc1BzfMpxvA==",
       "optional": true,
       "dependencies": {
-        "fill-range": "^7.0.1"
+        "fill-range": "^7.1.1"
       },
       "engines": {
         "node": ">=8"
@@ -1344,9 +1344,9 @@
       }
     },
     "node_modules/fill-range": {
-      "version": "7.0.1",
-      "resolved": "https://registry.npmjs.org/fill-range/-/fill-range-7.0.1.tgz",
-      "integrity": "sha512-qOo9F+dMUmC2Lcb4BbVvnKJxTPjCm+RRpe4gDuGrzkL7mEVl/djYSu2OdQ2Pa302N4oqkSg9ir6jaLWJ2USVpQ==",
+      "version": "7.1.1",
+      "resolved": "https://registry.npmjs.org/fill-range/-/fill-range-7.1.1.tgz",
+      "integrity": "sha512-YsGpe3WHLK8ZYi4tWDg2Jy3ebRz2rXowDxnld4bkQB00cc/1Zw9AWnC0i9ztDJitivtQvaI9KaLyKrc+hBW0yg==",
       "optional": true,
       "dependencies": {
         "to-regex-range": "^5.0.1"
@@ -3467,12 +3467,12 @@
       }
     },
     "braces": {
-      "version": "3.0.2",
-      "resolved": "https://registry.npmjs.org/braces/-/braces-3.0.2.tgz",
-      "integrity": "sha512-b8um+L1RzM3WDSzvhm6gIz1yfTbBt6YTlcEKAvsmqCZZFw46z626lVj9j1yEPW33H5H+lBQpZMP1k8l+78Ha0A==",
+      "version": "3.0.3",
+      "resolved": "https://registry.npmjs.org/braces/-/braces-3.0.3.tgz",
+      "integrity": "sha512-yQbXgO/OSZVD2IsiLlro+7Hf6Q18EJrKSEsdoMzKePKXct3gvD8oLcOQdIzGupr5Fj+EDe8gO/lxc1BzfMpxvA==",
       "optional": true,
       "requires": {
-        "fill-range": "^7.0.1"
+        "fill-range": "^7.1.1"
       }
     },
     "browserslist": {
@@ -3748,9 +3748,9 @@
       }
     },
     "fill-range": {
-      "version": "7.0.1",
-      "resolved": "https://registry.npmjs.org/fill-range/-/fill-range-7.0.1.tgz",
-      "integrity": "sha512-qOo9F+dMUmC2Lcb4BbVvnKJxTPjCm+RRpe4gDuGrzkL7mEVl/djYSu2OdQ2Pa302N4oqkSg9ir6jaLWJ2USVpQ==",
+      "version": "7.1.1",
+      "resolved": "https://registry.npmjs.org/fill-range/-/fill-range-7.1.1.tgz",
+      "integrity": "sha512-YsGpe3WHLK8ZYi4tWDg2Jy3ebRz2rXowDxnld4bkQB00cc/1Zw9AWnC0i9ztDJitivtQvaI9KaLyKrc+hBW0yg==",
       "optional": true,
       "requires": {
         "to-regex-range": "^5.0.1"

package.json

@@ -1,10 +1,11 @@
 {
   "name": "xmpp-lightning-antispam",
-  "version": "1.0.0",
-  "description": "",
+  "version": "1.2.0",
+  "description": "A bot for moderated XMPP channels, offering voice for Lightning donations",
   "main": "index.js",
   "type": "module",
   "scripts": {
+    "start": "node index.js",
     "test": "echo \"Error: no test specified\" && exit 1"
   },
   "author": "Râu Cao",

samples/xmpp-lightning-antispam.service

@@ -0,0 +1,13 @@
+[Unit]
+Description=XMPP Lightning Antispam bot
+After=network.target
+
+[Service]
+Type=simple
+User=deploy
+WorkingDirectory=/opt/xmpp-lightning-antispam
+ExecStart=/usr/bin/node index.js
+Restart=on-failure
+
+[Install]
+WantedBy=multi-user.target