glom

Tranformation chain utilizing an accumulating mixin (called a glom) input parameter.

Install

npm install glom

Example

If one was to describe the atomic actions required to create a new account using a chain of asynchronous functions, your Glom would look like this:

// A chain of business rules for account creation
new Glom([
  validateUserInput,
  isEmailUnique,
  createUser,
  [createDefaultPermissions, deleteUser, createError, returnJson]  // Sidechain in case of failure
  notifyAdmin,
  registerNewUserStats,
  returnJson
]).run({
  email: '[email protected]',
  password: 'woooo'
}, console.log, console.error);

Additional Usage

var Glom = require('glom');

function incrementData (value, next, error) {
    done({
        value: value + 1
    });

}

function setDataSnapshot (value, next, error) {
    this.snapshots.set('value', value);
    done();
}

function doubleData (value, next, error) {
    if (value > 5) {
        error('Data is too big.');
    } else {
        done({
            value: value * 2
        });
    }
}

function printData (value, next, error) {
    console.log(value);
    done();
}

function revertToSnapshot (messages, next, error) {
    done({
        value: this.snapshots.get('value')
    });
}

Glom([
    incrementData,
    getDataSnapshot,
    [doubleData, revertToSnapshot],
    printData
]).run({
    value: 3
}, function glomDone (glom) {
    console.log('Glom complete with final transformation:');
    console.dir(glom);
}, console.error);

Notice that each method in a Glom has its own parameters, allowing any simple, testable, and potentially isomorphic method to be used by Glom, provided the last two parameters are callbacks named next and error. Please see the tests for more use cases.