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tlab-trading-toolkit

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A trading toolkit for building advanced trading bots on the GDAX platform

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"use strict"; /*************************************************************************************************************************** * @license * * Copyright 2017 Coinbase, Inc. * * * * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance * * with the License. You may obtain a copy of the License at * * * * http://www.apache.org/licenses/LICENSE-2.0 * * * * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on * * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the * * License for the specific language governing permissions and limitations under the License. * ***************************************************************************************************************************/ Object.defineProperty(exports, "__esModule", { value: true }); const request = require("superagent"); const FXProvider_1 = require("../FXProvider"); const Big = require("bignumber.js"); const API_URL = 'https://openexchangerates.org/api'; let supportedCurrencies = null; class OpenExchangeProvider extends FXProvider_1.FXProvider { constructor(config) { super(config); this.apiKey = config.apiKey || process.env.OPENEXCHANGE_API_KEY; } get name() { return 'Open Exchange Rates'; } downloadCurrentRate(pair) { const query = { base: pair.from, symbols: pair.to, app_id: this.apiKey }; return request.get(API_URL + '/latest.json') .accept('application/json') .query(query) .then((res) => { const result = JSON.parse(res.body); const rate = result && result.rates && result.rates[pair.to]; if (!rate || !isFinite(rate)) { const error = new FXProvider_1.EFXRateUnavailable('We got a response, but the FX rates weren\'t present', this.name); return Promise.reject(error); } return Promise.resolve({ from: pair.from, to: pair.to, rate: new Big(rate), time: new Date() }); }); } supportsPair(pair) { if (supportedCurrencies) { return Promise.resolve(isSupported(pair)); } return request.get(API_URL + '/currencies.json') .accept('application/json') .then((res) => { const curs = res.body; supportedCurrencies = Object.keys(curs); return Promise.resolve(isSupported(pair)); }); } } exports.default = OpenExchangeProvider; function isSupported(pair) { return supportedCurrencies && supportedCurrencies.indexOf(pair.from) >= 0 && supportedCurrencies.indexOf(pair.to) >= 0; }