proback.js

proback.js - dependency-free very minimal helper for APIs with Promise/callback dual design



========

proback.js is an extremely tiny helper library to help the creation of APIs where functions are aimed to enable Promise-based and callback-based design as well.

Usage
Rules

Usage

Command line:

npm install proback.js --save

In JS code:

``javascript
var Proback = require('proback.js');
...
// your service. If callback is present, works as expected, If not, promise will be provided.
function yourService( data, callback ){
new Promise( function (resolve, reject) {
//some callback is needed?
object.fnCallWithCallback( data, Proback.handler( null, resolve, reject ) )
}).then( function (res) {
expect(res).to.equal('Done.')
done()
})
}
`

`javascript
var Proback = require('proback.js');
...
// your service. If callback is present, works as expected, If not, promise will be provided.
function yourService( data, callback ){
return new Promise( function (resolve, reject) {
//some callback is needed?
object.fnCallWithCallback( data, function (err, res) {
if (err) return Proback.rejecter(err, null, reject)
// some operation
return Proback.resolver(res, null, resolve)
} )
}).then( function (res) {
expect(res).to.equal('Done.')
done()
})
}
``

Rules

- quicker ( res, callback )
Defines a simple promise to send a result through the optional callback as well

- thrower ( err, callback )
Defines a simple promise to throw an error through the optional callback as well

- syncAll (promises)
Performes all promises in order

- forAll ( promises, callback, defaultRes )
Performes all promises and channel the result to the given callback

- handler ( callback, resolve, reject )
Defines a callback function, which will use the passed opional callback and promise functions to channel the results

- returner ( err, res, callback, resolve, reject )
Error mades it mark the error through the optional callback and the optional reject function or send the result back to the optional callback or the optional resolve function

- resolver (res, callback, resolve)
Sends a result through the optional callback and the optional reject function

- rejecter (err, callback, reject)
Marks an error through the optional callback and the optional reject function