controlled-promise
Better control of JavaScript Promises
A Promise wrapping library for advanced control of promise lifecycle. Allows to split business logic from promise manipulation:
- promisify event-emitters: easy access to
resolve/rejectcallbacks - return existing promise while it is pending
- auto-reject after configured timeout
- tiny size and zero dependencies
Installation
npm install controlled-promise --saveUsage
const ControlledPromise = require('controlled-promise');
// Create controlled promise
const cp = new ControlledPromise();
// Call asynchronous function. Returns promise wich `resolve / reject` callbacks are stored in `cp`.
const promise = cp.call(() => someAsyncFn());
// Resolve promise later via cp.resolve()
cp.resolve();
// OR reject promise later via cp.reject()
cp.reject(error);API
ControlledPromise
Controlled Promise.Kind: global class
* [new ControlledPromise()](#new_ControlledPromise_new)
* [.promise](#ControlledPromise+promise) ⇒ <code>Promise</code>
* [.value](#ControlledPromise+value) ⇒ <code>\*</code>
* [.isPending](#ControlledPromise+isPending) ⇒ <code>Boolean</code>
* [.isFulfilled](#ControlledPromise+isFulfilled) ⇒ <code>Boolean</code>
* [.isRejected](#ControlledPromise+isRejected) ⇒ <code>Boolean</code>
* [.isSettled](#ControlledPromise+isSettled) ⇒ <code>Boolean</code>
* [.isCalled](#ControlledPromise+isCalled) ⇒ <code>Boolean</code>
* [.call(fn)](#ControlledPromise+call) ⇒ <code>Promise</code>
* [.resolve([value])](#ControlledPromise+resolve)
* [.reject([value])](#ControlledPromise+reject)
* [.reset()](#ControlledPromise+reset)
* [.timeout(ms, [reason])](#ControlledPromise+timeout)new ControlledPromise()
Creates controlled promise. In contrast to original Promise, it does not immediately call any function. Instead it has .call() method for that andresolve / reject methods for
resolving promise.controlledPromise.promise ⇒ Promise
Returns promise itself.Kind: instance property of
ControlledPromisecontrolledPromise.value ⇒ \*
Returns value with that promise was fulfilled (resolved or rejected).Kind: instance property of
ControlledPromisecontrolledPromise.isPending ⇒ Boolean
Returns true if promise is pending.Kind: instance property of
ControlledPromisecontrolledPromise.isFulfilled ⇒ Boolean
Returns true if promise is fulfilled.Kind: instance property of
ControlledPromisecontrolledPromise.isRejected ⇒ Boolean
Returns true if promise rejected.Kind: instance property of
ControlledPromisecontrolledPromise.isSettled ⇒ Boolean
Returns true if promise fulfilled or rejected.Kind: instance property of
ControlledPromisecontrolledPromise.isCalled ⇒ Boolean
Returns true if promise already called via .call() method.Kind: instance property of
ControlledPromisecontrolledPromise.call(fn) ⇒ Promise
This method executes fn and returns promise. While promise is pending all subsequent calls of .call(fn)
will return the same promise. To fulfill that promise you can use .resolve() / .reject() methods.Kind: instance method of
ControlledPromise| Param | Type | | --- | --- | | fn |
function | controlledPromise.resolve(value)
Resolves pending promise with specifiedvalue.Kind: instance method of
ControlledPromise| Param | Type | | --- | --- | | value |
\* | controlledPromise.reject(value)
Rejects pending promise with specifiedvalue.Kind: instance method of
ControlledPromise| Param | Type | | --- | --- | | value |
\* | controlledPromise.reset()
Resets to initial state.Kind: instance method of
ControlledPromisecontrolledPromise.timeout(ms, reason)
Sets timeout to reject promise automatically.Kind: instance method of
ControlledPromise| Param | Type | Description | | --- | --- | --- | | ms |
Number | delay in ms after that promise will be rejected automatically |
| reason | String \| Error \| function | rejection value. If it is string or error - promise will be rejected with that error. If it is function - this function will be called after delay where you can manually resolve or reject promise via .resolve() / .reject() methods. |