README
uvrun2
Copyright
(C) 2015 Jeff Walter jeff@404ster.com, http://jwalter.sh/
License
This module is licensed under the MIT License (MIT). Please see the accompanying LICENSE file for more information.
Contributions
None yet
Requirements
- NodeJS >= 0.11.0
Installation
The easiest way is to use NPM:
npm install uvrun2
You can also clone this repo and build the module yourself:
git clone https://github.com/jeffwalter/node-uvrun2.git
cd node-uvrun2
node-gyp configure build
Testing
Dirt simple:
npm test
Usage
Running the loop once and handling a single event:
var uvRunOnce = require ('uvrun2').runOnce;
setTimeout (function () { console.info ("Hello!"); }, 5000);
while (1) {
uvRun ();
}
Pause code to wait for an asynchronous call to complete:
var uvWaitFor = require ('uvrun2').waitFor;
var wait = new uvWaitFor ();
setTimeout (function () {wait.provide (1);}, 5000);
var returnValue = wait.accept ();
Methods
uvrun2.runOnce (nonBlocking = false)
Process a single event from the libuv loop. By default this call will block
until it has processed an event, but you can pass true
as the sole argument
causing the call to either process a waiting event or return immediately.
Classes
uvrun2.waitFor
A class added for convenience. It's designed to allow synchronizing of
asynchronous functions. Why would you want to do that? Maybe you're getting a
little deep into callback hell. Maybe you'd like to serialize a section of code
but don't feel async
is the way to go. Whatever the reason, this will handle
the task.
Basically the class pauses execution at the variable assignment spinning over a
uvrun2.runOnce (true)
(see above) while checking for a provided value. Once
it sees a value it is returned. Meanwhile, asynchronous events and code
continue to run.
Please note that waitFor
will only allow a single value to be provided in
each instance. They cannot be re-used.
new uvrun2.waitFor ()
Constructs a new waitFor
instance. It has no arguments.
uvrun2.waitFor.accept (block = true)
Use this to assign the result of the asynchronous code to a variable. You can
use the block
argument to control the call to uvrun2.runOnce()
. Setting
block
to true will set nonBlocking
to false and visa versa. The
functionality is identical, but setting block
to true
has the effect of
lowering CPU use by removing the spin on uvrun2.runOnce()
. It is recommended
to use the default value by either not passing a value for block
or by
setting it to true
.
uvrun2.waitFor.provide (value)
Goes in the asynchronous call to provide the value back to the accept()
call.