check-markets-crypto v1.0.1

check-markets-crypto

Check conditions against exchanges available in ccxt module.

Installation

NPM

$ npm install check-markets-crypto

Example

const controller = require('check-markets-crypto')

let obj = {
  "exchanges": [
    {
      "name": 'bittrex',
      "period": 1000,
      "checkers": [
        {
          'name': 'test-1-bittrex',
          'condition': (lastTicker, currentTicker) => currentTicker.symbol === 'BTC/USDT',
          'update': (lastTicker, currentTicker) => currentTicker,
          'do': data => console.log(data)
        },
        {
          'name': 'test-2-bittrex',
          'condition': (lastTicker, currentTicker) => currentTicker.symbol === 'BCH/USDT',
          'update': (lastTicker, currentTicker) => currentTicker,
          'do': data => console.log(data)
        }
      ],
      "error": function (error) {
        console.log(error)
        this.getTickers()
      }
    },
    {
      "name": 'poloniex',
      "period": 1000,
      "checkers": [
        {
          'name': 'test-1-poloniex',
          'condition': (lastTicker, currentTicker) => currentTicker.symbol === 'BTC/USDT',
          'update': (lastTicker, currentTicker) => currentTicker,
          'do': data => console.log(data)
        },
        {
          'name': 'test-2-poloniex',
          'condition': (lastTicker, currentTicker) => currentTicker.symbol === 'BCH/USDT',
          'update': (lastTicker, currentTicker) => currentTicker,
          'do': data => console.log(data)
        }
      ],
      "error": function (error) {
        console.log(error)
        this.getTickers()
      }
    }
  ]
}

controller(obj)

Use

The module is a fuction which you pass a array of objects, each object must have the following properties:

• "name": Exchange ID defined in ccxt module, click to see the exchanges avaible and their ID´s.
• "period": Time to wait before make another REST request to the exchange (milliseconds).
• "checkers": Array of objects which you use to define conditions to check, below you will find an explanation to this.
• "error": Error handler, when the request could not work you receive an error here. So you can decide what to do, and if you want to still making request you execute "this.getTickers()".

The properties of a checker object is the following:

• "name": This name is to identify the condition used to check in the data received in "do" method, because you can have an array of them.
• "condition": Condition to check against the tickers - You receive two tickers (last and current) to check.
• "update": Function to decide which ticker must be the last - You receive two tickers (last and current) to decide.
• "do": You receive here the tickers who accomplish the condition.

To check if the market accomplish a condition you need two tickers. Usually lastTicker is taken in a previous time than currentTicker, but you can decide which must be the lastTicker in a update method. In every ticker you receive the information of all markets in the exchange. In the ccxt documentation you can see how it is strutured the tickers and how it works on the exchange, the method used is "fetchTickers".