A tiny error in a node.js code. Need a fix!

    ygreq
    Oct 06 2018 | 8:44 pm
    Hi folks,
    I am trying to figure out how to make a small app that for now should track Binance exchange prices. I want to change from Max which tickers to track. But I have a problem with the node.js code.
    Any idea how I should go about doing this in order to have the same output? I have 2 of Max.post and now I get an error on the second one. Do you know what I am doing wrong? node.script: [ "Price of BTCUSDT: ", "6591.57000000" ] node.script: [ "Price of BTCUSDT: ", null ] It's missing the nmp package which can be found here https://www.npmjs.com/package/node-binance-api. But the code is basic for someone with more knowledge than me :)
    And the node.js code is this: const path = require('path'); const Max = require('max-api'); var nodeBinanceApi = require("node-binance-api"); var tickerName; // Holds the ticker pair name (eg BTCUSDT) const binance = require('node-binance-api')().options({ APIKEY: '<key>', APISECRET: '<secret>', useServerTime: true, // If you get timestamp errors, synchronize to server time at startup test: true // If you want to use sandbox mode where orders are simulated }); // This will be printed directly to the Max console Max.post(`loaded the ${path.basename(__filename)} script`); // Use the 'addHandler' function to register a function for a particular message Max.addHandler("tickerNameSelector", (tickerName) => { binance.prices(tickerName, (error, ticker) => { Max.post("Price of BTCUSDT: ", ticker.BTCUSDT); Max.post("Price of BTCUSDT: ", ticker.tickerName); }); }); Thank you so much!! ygreq
    • ygreq
      Oct 07 2018 | 9:05 am
      It works!!! Thank you so much!! :D And I appreciate the info regarding how your solution works.
    • Florian Demmer
      Oct 07 2018 | 4:07 pm
      Raja covered most here I guess but I'd advise to avoid eval unless very very necessary. So yeah, just for reference you could use the following "bracket notation property accessor":
      ticker[tickerName]
      in order to access a property of the ticker object using a variable. For more context you can also head over to MDN for a more reference style explanation with examples: https://developer.mozilla.org/en-US/docs/Learn/JavaScript/Objects/Basics And yeah, for completeness the full code again:
      const path = require("path");
const Max = require("max-api");
const nodeBinanceApi = require("node-binance-api");

let tickerName; // Holds the ticker pair name (eg BTCUSDT)

const binance = require("node-binance-api")().options({
  APIKEY: "<key>",
  APISECRET: "<secret>",
  // If you get timestamp errors, synchronize to server time at startup
  useServerTime: true,
  // If you want to use sandbox mode where orders are simulated
  test: true 
});

// This will be printed directly to the Max console
Max.post(`loaded the ${path.basename(__filename)} script`);

// Use the 'addHandler' function to register a function for a particular message
Max.addHandler("tickerNameSelector", (tickerName) => {
  binance.prices(tickerName, (error, ticker) => {
    Max.post("Price of BTCUSDT: ", ticker.BTCUSDT);
    Max.post("Price of BTCUSDT: ", ticker[tickerName]);
  });
});
    • ygreq
      Oct 07 2018 | 10:51 pm
      Thank you, Florian. May I ask why not use eval?
    • ygreq
      Oct 08 2018 | 6:22 pm
      Thank you for info, MC WRAPPIN R∆J∆!