Automaticcaly roll between multiple signing keys.

- Handle a list of signing keys.
- Detect current key used, and switch to the next one if needed/requested.
- Avoid to input a new key after a key switch;
- Update documentation and commands accordingly.

README.md

@@ -24,7 +24,7 @@ Open config-sample.json in your favourite text editor and edit with your own set
     "missed_block_threshold": 3,
     "checking_interval": 10,
     "reset_period": 300,
-    "backup_key": "BTSXXXXXXXXXXXXXXXXXX",
+    "witness_signing_keys": [ "BTSXXXXXXXXXXXXXXXXXX", "BTSYYYYYYYYYYYYYYY"],
     "recap_time": 60,
     "debug_level": 3,
     "telegram_token": "<telegram_access_token>",
@@ -40,10 +40,12 @@ and then save as config.json
 
 | Key | Description |
 | --- | --- |
+| `witness_id` | The id of the witness to monitor. |
+| `api_node` | Bitshares Websocket url to use to retrieve blockchain information. |
 | `private_key`  | The active key of your normal witness-owning account used to sign the witness_update operation. |
 | `missed_block_threshold`  | How many blocks must be missed within a `reset_period` sec window before the script switches your signing key. Recommend to set at 2 or higher since 1 will possibly trigger updates on maintenance intervals (see [bitshares-core#504](https://github.com/bitshares/bitshares-core/issues/504)). |
 | `checking_interval` | How often should the script check for new missed blocks in seconds. |
-| `backup_key`  | The public signing key of your backup witness to be used when switching. |
+| `witness_signing_keys`  | All the public keys of your witness, to switch key if too many blocks are missed. |
 | `recap_time`  | The interval in minutes on which bot will auto-notify telegram user of latest stats (if authenticated). |
 | `reset_period`  | The time after which the missed blocks counter is reset for the session in seconds. |
 | `debug_level`  | Logging level. Can be: _0_ (Minimum - Explicit logging & Errors, _1_ (Info - 0 + Basic logging), _2_ (Verbose - 1 + Verbose logging),  _3_. Transient - 2 + Transient messages.  Not currently used. |
@@ -99,8 +101,8 @@ Open a chat to your bot and use the following:
 - `/start`: Introduction message.
 - `/help`: Get the list of available commands. 
 - `/stats`: Return the current configuration and statistics of the monitoring session.
-- `/switch`: IMMEDIATELY update your signing key to the currently configured backup key.
-- `/new_key <BTS_public_signing_key>`: Set a new backup key in place of the configured one.
+- `/switch`: IMMEDIATELY update your signing key to the new available signing key.
+- `/signing_keys <BTS_public_signing_key1> <BTS_public_signing_key2>`: Set a new list of public keys.
 - `/new_node wss://<api_node_url>`: Set a new API node to connect to.
 - `/threshold X`: Set the missed block threshold before updating signing key to X blocks.
 - `/interval Y`: Set the checking interval to every Y seconds.
@@ -122,7 +124,7 @@ start - Introduction
 help - List all commands
 stats - Gather statistics
 switch - Update signing key to backup
-new_key - Set a new backup key
+signing_keys - Set signing keys
 new_node - Set a new API node to connect to
 threshold - Set the missed block threshold
 interval - Set the checking interval

config-sample.json

@@ -5,7 +5,7 @@
     "missed_block_threshold": 3,
     "checking_interval": 10,
     "reset_period": 300,
-    "backup_key": "",
+    "witness_signing_keys": [],
     "recap_time": 60,
     "debug_level": 3,
     "telegram_token": "",

index.js

@@ -20,7 +20,8 @@ function send_stats(recipient_id) {
     const current_stats = witness_monitor.current_statistics();
     let stats = [
         `Total missed blocks: \`${current_stats.total_missed}\``,
-        `Missed blocks in current time window: \`${current_stats.current_missed}\``,
+        `Missed blocks in current time window: \`${current_stats.window_missed}\``,
+        `Current signing key: \`${current_stats.signing_key}\``,
         `Feed publications: `
     ]
     current_stats.feed_publications.forEach(feed_stat => {
@@ -37,7 +38,7 @@ function send_settings(recipient_id) {
         `Node failed connection attempt notification threshold: \`${config.retries_threshold}\``,
         `Missed block threshold: \`${config.missed_block_threshold}\``,
         `Missed block reset time window: \`${config.reset_period} sec\``,
-        `Backup signing key: \`${config.backup_key}\``,
+        `Public signing keys: ${config.witness_signing_keys.map(k => '`' + k + '`').join(', ')}`,
         `Recap time period: \`${config.recap_time} min\``,
         `Feeds to check: \`${config.feeds_to_check}\``,
         `Feed publication treshold: \`${config.feed_publication_threshold} min\``,
@@ -65,8 +66,8 @@ bot.onText(/\/start/, (msg) => {
 bot.onText(/\/help/, (msg) => {
     const help = [
         `\`/stats\`: Return the current configuration and statistics of the monitoring session.`,
-        `\`/switch\`: IMMEDIATELY update your signing key to the currently configured backup key.`,
-        `\`/new_key <BTS_public_signing_key>\`: Set a new backup key in place of the configured one.`,
+        `\`/switch\`: IMMEDIATELY update your signing key to the next available signing key.`,
+        `\`/signing_keys <BTS_public_signing_key1> <BTS_public_signing_key2>\`: Set a new list of public keys.`,
         `\`/new_node wss://<api_node_url>\`: Set a new API node to connect to.`,
         `\`/threshold X\`: Set the missed block threshold before updating signing key to X blocks.`,
         `\`/interval Y\`: Set the checking interval to every Y seconds.`,
@@ -95,14 +96,15 @@ bot.onText(/\/reset/, (msg, match) => {
 
 });
 
-bot.onText(/\/new_key (.+)/, (msg, match) => {
+bot.onText(/\/signing_keys (.+)/, (msg, match) => {
 
     const chatId = msg.chat.id;
-    const key = match[1];
+    const keys = match[1].split(' ');
 
     if (checkAuthorization(chatId)) {
-        config.backup_key = key;
-        bot.sendMessage(chatId, `Backup signing key set to: ${config.backup_key}`);
+        config.witness_signing_keys = keys;
+        bot.sendMessage(chatId, `Signing keys set to: ${config.witness_signing_keys.map(k => '`' + k + '`').join(', ')}`,
+            { parse_mode: 'Markdown' });
     }
 
 });

lib/WitnessMonitor.js

@@ -5,7 +5,6 @@ const moment = require('moment');
 const FeedStat = require('./FeedStat.js');
 
 class WitnessMonitor extends EventEmitter {
-
 
     constructor(config, logger) {
         super();
@@ -19,16 +18,17 @@ class WitnessMonitor extends EventEmitter {
         this._checking = false;
         this._witness_account = null;
         this._witness_url = null;
+        this._witness_current_signing_key = null;
         this._feed_stats = null;
         this._last_feed_check = null;
         this._node_retries = 0;
     }
-
 
     current_statistics() {
         return {
             total_missed : this._total_missed,
-            current_missed : this._total_missed - this._start_missed,
+            window_missed : this._total_missed - this._start_missed,
+            signing_key : this._witness_current_signing_key,
             feed_publications : this._feed_stats
         }
     }
@@ -53,11 +53,18 @@ class WitnessMonitor extends EventEmitter {
                 return Apis.close();
             }
         });
+    }
 
+    find_next_signing_key() {
+        const i = this._config.witness_signing_keys.findIndex(k => k == this._witness_current_signing_key);
+        if (i == -1) {
+            return this._config.witness_signing_keys[0]; 
+        }
+        return this._config.witness_signing_keys[(i + 1) % this._config.witness_signing_keys.length];
     }
 
     update_signing_key() {
-        const private_key = PrivateKey.fromWif(this._config.private_key);
+        const backup_signing_key = this.find_next_signing_key();
         const tr = new TransactionBuilder();
         tr.add_type_operation('witness_update', {
             fee: {
@@ -67,21 +74,23 @@ class WitnessMonitor extends EventEmitter {
             witness: this._config.witness_id,
             witness_account: this._witness_account,
             new_url: this._witness_url,
-            new_signing_key: this._config.backup_key
+            new_signing_key: backup_signing_key
         });
 
         return tr.set_required_fees().then(() => {
+                const private_key = PrivateKey.fromWif(this._config.private_key);
                 tr.add_signer(private_key, private_key.toPublicKey().toPublicKeyString());
                 return tr.broadcast();
             })
             .then(() => {
                 this.reset_missed_block_window();
-                this.notify('Signing key updated');
+                this.notify(`Signing key updated to: ${backup_signing_key}`);
             }).catch(() => {
                 this.notify('Could not broadcast update_witness tx.');
             });
 
     }
+
     notify(msg) {
         this._logger.log(msg);
         this.emit('notify', msg)
@@ -176,7 +185,8 @@ class WitnessMonitor extends EventEmitter {
                 this._logger.log('Connected to API node: ' + this._config.api_node);
                 return Apis.instance().db_api().exec('get_objects', [[this._config.witness_id]]).then((witness) => {
                     this._witness_account = witness[0].witness_account;
-                    this._witness_url = witness[0].url
+                    this._witness_url = witness[0].url;
+                    this._witness_current_signing_key = witness[0].signing_key;
                     this._total_missed = witness[0].total_missed;
 
                     const should_reset_window = moment().diff(this._window_start, 'seconds') >= this._config.reset_period