Introduce Trade Class (#1968)

* subtract candle length from start time to calculate isPremature

* Move startTimeMinusCandleSize inside realtime if check

* return the indicator after adding it

* develop trade class

* make fixes after live market test

* line spacing

* rollback package-lock.json to develop branch

* link to discussion:

* move methods from portfolio manager into trade class and new portfolio class

* cleanup logging, comments

plugins/trader/portfolio.js

@@ -0,0 +1,111 @@
+/*
+  The Portfolio class holds the most recent data about the portfolio and ticker
+*/
+
+var _ = require('lodash')
+var util = require('../../core/util')
+var dirs = util.dirs()
+var events = require('events')
+var log = require(dirs.core + 'log')
+var async = require('async')
+
+class Portfolio{
+  constructor(conf,exchange){
+    _.bindAll(this)
+    this.conf = conf
+    this.exchange = exchange
+    this.portfolio = {}
+    this.fee = null
+    this.ticker = null
+  }
+
+  getBalance(fund) {
+    return this.getFund(fund).amount;
+  }
+
+  // return the [fund] based on the data we have in memory
+  getFund(fund) {
+    return _.find(this.portfolio, function(f) { return f.name === fund});
+  }
+
+  // convert into the portfolio expected by the performanceAnalyzer
+  convertPortfolio(asset,currency) { // rename?
+    var asset = _.find(this.portfolio, a => a.name === this.conf.asset).amount;
+    var currency = _.find(this.portfolio, a => a.name === this.conf.currency).amount;
+
+    return {
+      currency,
+      asset,
+      balance: currency + (asset * this.ticker.bid)
+    }
+  }
+
+  logPortfolio() {
+    log.info(this.exchange.name, 'portfolio:');
+    _.each(this.portfolio, function(fund) {
+      log.info('\t', fund.name + ':', parseFloat(fund.amount).toFixed(12));
+    });
+  };
+
+  setPortfolio(callback) {
+    let set = (err, fullPortfolio) => {
+      if(err)
+        util.die(err);
+
+      // only include the currency/asset of this market
+      const portfolio = [ this.conf.currency, this.conf.asset ]
+        .map(name => {
+          let item = _.find(fullPortfolio, {name});
+
+          if(!item) {
+            log.debug(`unable to find "${name}" in portfolio provided by exchange, assuming 0.`);
+            item = {name, amount: 0};
+          }
+
+          return item;
+        });
+
+      this.portfolio = portfolio;
+
+      if(_.isEmpty(this.portfolio))
+        this.emit('portfolioUpdate', this.convertPortfolio(this.conf.asset,this.conf.currency,this.ticker.bid));
+
+      if(_.isFunction(callback))
+        callback();
+
+    }
+
+    this.exchange.getPortfolio(set);
+  }
+
+  setFee(callback) {
+    let set = (err, fee) => {
+      this.fee = fee;
+
+      if(err)
+        util.die(err);
+
+      if(_.isFunction(callback))
+        callback();
+    }
+    this.exchange.getFee(set);
+  }
+
+  setTicker(callback) {
+    let set = (err, ticker) => {
+      this.ticker = ticker;
+
+      if(err)
+        util.die(err);
+
+      if(_.isFunction(callback))
+        callback();
+    }
+    this.exchange.getTicker(set);
+  }
+
+}
+
+util.makeEventEmitter(Portfolio)
+
+module.exports = Portfolio