Merge pull request #8 from akinwale/master

Price bot implementation pull request
@lyoshenka this will need the MARKET_TRADING_CHANNEL env variable and a npm install!

app.js

@@ -32,6 +32,9 @@ hashbot.init(slackbot, process.env.MINING_CHANNEL);
 var claimbot = require('./bots/claimbot');
 claimbot.init(slackbot, process.env.CLAIMS_CHANNEL, process.env.RPCUSER, process.env.RPCPASSWORD, process.env.MONGODB_URL);
 
+var pricebot = require('./bots/pricebot');
+pricebot.init(process.env.MARKET_TRADING_CHANNEL);
+
 slackbot.on('start', function() {
   slackbot.on('message', function(data) {
     if (data.type == 'team_join') {
@@ -63,6 +66,10 @@ slackbot.on('start', function() {
       if (command === tipbot.command) {
         tipbot.respond(slackbot, data);
       }
+
+      if (command === pricebot.command) {
+        pricebot.respond(slackbot, data);
+      }
     }
   });
 });

bots/pricebot.js

@@ -0,0 +1,172 @@
+var jp = require('jsonpath');
+var moment = require('moment');
+var numeral = require('numeral');
+var request = require('request');
+
+var options = {
+    defaultCurrency: 'USD',
+
+    // supported currencies and api steps to arrive at the final value
+    currencies: {
+        USD: { steps: ['LBCBTC', 'BTCUSD'], format: '$0,0.00' },
+        BTC: { steps: ['LBCBTC'], format: '0,0[.][00000000] BTC' }
+    },
+
+    // api steps
+    api: {
+        LBCBTC: { url: 'https://bittrex.com/api/v1.1/public/getticker?market=BTC-LBC', path: '$.result.Bid' },
+        BTCUSD: { url: 'https://blockchain.info/ticker', path: '$.USD.buy' }
+    },
+
+    // display date/time format
+    dtFormat: 'Do MMM YYYY h:mma [UTC]',
+
+    // refresh rate in milliseconds to retrieve a new price (default to 10 minutes)
+    refreshTime: 600000
+};
+
+// store the last retrieved rate
+var cachedRates = {};
+
+var mktChannel;
+
+// !price {currency}
+// !price {currency} {amount}
+var command = '!price';
+
+module.exports={
+  command: command,
+  init: init,
+  respond: respond
+};
+
+function init(channel_) {
+  mktChannel = channel_;
+  if (!channel_) {
+    console.log('No market and trading channel. Pricebot will only respond to #bot-sandbox and DMs.');
+  }
+
+  var currencies = Object.keys(options.currencies);
+  for (var i = 0; i < currencies.length; i++) {
+    cachedRates[currencies[i]] = { rate: 0, time: null };
+  }
+}
+
+var globalSlackParams = {};
+
+function respond(bot, data) {
+  var channel = data.channel,
+      words = data.text.trim().split(' ').filter( function(n){return n !== "";} );
+
+  if (words[0] !== command || (channel != mktChannel && channel !== 'C1TEEBS2Z' && !channel.startsWith('D'))) {
+    // if the received message isn't starting with the trigger,
+    // or the channel is not the market-and-trading channel, nor sandbox, nor a DM -> ignore
+    return;
+  }
+
+  var currency = (words.length > 1) ? words[1].toUpperCase() : options.defaultCurrency;
+  var amount = (words.length > 2) ? parseFloat(words[2], 10) : 1;
+  var showHelp = (isNaN(amount)) || (Object.keys(options.currencies).indexOf(currency) === -1);
+
+  var moveToBotSandbox = showHelp && channel !== 'C1TEEBS2Z' && !channel.startsWith("D");
+  if (moveToBotSandbox) {
+    bot.postMessage(channel, 'Please use <#C1TEEBS2Z|bot-sandbox> to talk to bots.', globalSlackParams);
+    return;
+  }
+
+  if (showHelp) {
+    doHelp(bot, channel);
+  } else {
+    doSteps(bot, channel, currency, amount);
+  }
+}
+
+function doHelp(bot, channel) {
+  var message =
+    '`' + command + '`: show the price of 1 LBC in ' + options.defaultCurrency + '\n' +
+    '`' + command + ' help`: this message\n' +
+    '`' + command + ' CURRENCY`: show the price of 1 LBC in CURRENCY. Supported values for CURRENCY are *btc* and *usd* (case-insensitive)\n' +
+    '`' + command + ' CURRENCY AMOUNT`: show the price of AMOUNT LBC in CURRENCY\n';
+
+    if (!channel.startsWith("D")) {
+      message =
+        '*USE <#C1TEEBS2Z|bot-sandbox> FOR HELP*\n' +
+        message +
+        '\n' +
+        '*Everyone will see what I say. Send me a Direct Message if you want to interact privately.*\n' +
+        'If I\'m not responding in some channel, you can invite me by @mentioning me.\n';
+    }
+
+  bot.postMessage(channel, message, globalSlackParams);
+}
+
+function formatMessage(amount, rate, option) {
+    var value = numeral(rate.rate * amount).format(option.format);
+    return '*' + numeral(amount).format('0,0[.][00000000]') + ' LBC = ' + value + '*\n_last updated ' + rate.time.utc().format(options.dtFormat) + '_';
+}
+
+function doSteps(bot, channel, currency, amount) {
+    var option = options.currencies[currency];
+    var shouldReload = true;
+    if (cachedRates[currency]) {
+        var cache = cachedRates[currency];
+        shouldReload = cache.time === null || moment().diff(cache.time) >= options.refreshTime;
+        if (!shouldReload) {
+            var message = formatMessage(amount, cache, option);
+            bot.postMessage(channel, message);
+        }
+    }
+
+    if (shouldReload) {
+        // copy the steps array
+        var steps = [];
+        for (var i = 0; i < option.steps.length; i++) {
+            steps.push(option.steps[i]);
+        }
+
+        processSteps(bot, channel, currency, 0, amount, steps, option);
+    }
+}
+
+function processSteps(bot, channel, currency, rate, amount, steps, option) {
+    if (steps.length > 0) {
+        var pairName = steps[0];
+        if (!options.api[pairName]) {
+            bot.postMessage(channel, 'There was a configuration error. ' + pairName + ' pair was not found.');
+            return;
+        }
+
+        var pair = options.api[pairName];
+        request.get(pair.url, function(error, response, body) {
+            if (error) {
+                bot.postMessage(channel, err.message ? err.message : 'The request could not be completed at this time. Please try again later.');
+                return;
+            }
+            var pairRate = 0;
+            try {
+                pairRate = jp.query(JSON.parse(body), pair.path);
+                if (Array.isArray(pairRate) && pairRate.length > 0) {
+                    pairRate = pairRate[0];
+                }
+            } catch (ignored) {
+                // invalid response or pair rate
+            }
+
+            if (pairRate > 0) {
+                rate = (rate === 0) ? pairRate : rate * pairRate;
+                steps.shift();
+                if (steps.length > 0) {
+                    processSteps(bot, channel, currency, rate, amount, steps, option);
+                    return;
+                }
+
+                // final step, cache and then response
+                var result = { rate: rate, time: moment() };
+                cachedRates[currency] = result;
+                bot.postMessage(channel, formatMessage(amount, result, option));
+            } else {
+                bot.postMessage(channel, 'The rate returned for the ' + pairName + ' pair was invalid.');
+            }
+        });
+    }
+}

package.json

@@ -6,9 +6,11 @@
   "dependencies": {
     "bitcoin": "^3.0.1",
     "imgur": "0.1.7",
+    "jsonpath": "0.2.11",
     "moment": "^2.17.1",
     "mongodb": "^2.2.22",
     "needle": "^1.0.0",
+    "numeral": "2.0.6",
     "request": "^2.81.0",
     "slackbots": "^0.5.1",
     "sleep": "^5.1.1",