Package Exports

realm-utils

This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (realm-utils) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.

Readme

realm-utils

Realm-js has a set of functionality that helps solving many problems or impediments related to Promises. Utilities live in this repository, apart from realm-js library. Typings included

Install

npm install realm-utils --save

import {each, chain, Chainable, utils} from 'realm-utils'; // typescript
const rutils = require('realm-utils'); // es6

Each

Iterates a list of promises (objects) consecutively. Respects promises if provided

var a = [1, 2, 3];
realm.each(a, (num) => {
  return new Promise((resolve, reject) => {
    setTimeout(function(){
      return resolve(num++)
    }, num);
  })
}).then(result => {
   // [2,3,4]
});

And another example with optional Promise

realm.each(a, (num) => {
  if( num ===3) {
    return new Promise((resolve, reject) => {
      setTimeout(function(){
        return resolve("gotcha")
      }, 1);
    })
  }
  return num;
}).then(result => {
  // [1, 2, "gotcha"]
})

Chains

Chain are very helpful when you have a logic flow, and you need to split it up, and keep you code clean. All methods are executed in strict order. You can call it a waterfall.

class MyChain {
   
   setFoo() {
      // I am the first one. And i set this.foo = "foo1"
      return "foo1";
   }
   setBar() {
      // I am the second one, and i have "this.foo" at my disposal
      // And i set this.bar = "bar1"
      return "bar1";
   }
   justSomethingFunky()
   {
     // I am the third one, and everyone will wait for me
     let self = this;
     return new Promise(function(resolve, reject){
        // But i will not assign anything
        // Just have to resolve myself
        return resolve(self.bar)
     })
   }
   setHello()
   {
      // I am the last to be executed, and i will assign this.hello = "world"
      return "world";
   }
}
realm.chain(MyChain).then(function(result){
   // {foo : "foo1", bar : "bar1", hello: "world" }   
});

Executes methods in defined order. If a setter is defined, realm will assign the result into the instance of a class.

Formatting the output

You can format the output as well using "format" method.

class MyChain {
   setFoo() {
      return "foo1";
   }
   setBar() {
      // I am still executed
      return "bar1";
   }
   format()
   {
      return {
        hello : this.foo
      }
   }
}
realm.chain(MyChain).then(function(result){
     // {hello : "foo1" }   
});