convert-callback-to-promise v0.0.2

convert-callback-to-promise

The function that can convert any callback-function to return a promise.

install

npm install convert-callback-to-promise

usage

convert-callback-to-promise just put data argument of callback function to promise.then and put error argument of callback function to promise.catch.

const callback = function (error, data) {
  if (error) {
    // error handler
  } else {
    // success handler
  }
};

const successHandler = function (data) {
  // success handler
}

const errorHandler = function (error) {
  // error handler
}

const callbackFunction = function (arg1, arg2, ..., callback){
  // ...
}

//the usage of callback function like this
callbackFunction(arg1, arg2, ..., callback);

// convert callback function and the usage like this
const promiseFunction = convert(callbackFunction);
promiseFunction(arg1, arg2, ...)
  .then(successHandler)
  .catch(errorHandler);

example

const fs = require('fs');
const convert = require('convert-callback-to-promise');

// callback
fs.readFile('data.json', 'utf-8', (error, data) => {
  if(error){
    console.error(error);
  } else{
    console.log(data.toString());
  }
});

// promise
const readFilePromise = convert(fs.readFile);

readFilePromise('data.json', 'utf-8')
  .then(data => console.log(data.toString()))
  .catch(error => console.error(error));