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    paddle

    1.0.0 • Public • Published

    Paddle

    You're up a creek; here's your Paddle. In Javascript, we rely on callback execution, often times without knowing for sure that it will happen. With Paddle, you can know. Paddle is a simple way of noting that your code should reach one of several code-execution points within a timelimit. If the time- limit is exceeded, an error callback is executed.

    Paddle is, simply, a way of creating an error_callback just in case your asynchronous code does not end up where you think it should in a time limit.

    Paddle was inspired by @mde's "You are fucked" section at his 2011 NodeConf talk.

    Install

    npm install paddle

    Usage

    Paddle Init

    var paddle = new Paddle(freq) // freq is the # of seconds to check on timeouts

    Methods

    paddle.insure(error_callback, timeout, args, id):
    Registers and returns and insurance object. args and id are optional.

    paddle.check_in(id):
    Confirm code execution and avoid the error_callback on insurance or id.

    paddle.start():
    Start checking for timed out insurances. (Started automatically).

    paddle.stop():
    Stop checking for timed out insurances.

    Insurance Objects

    Insurance objects are returned when you call insure. var insurance = paddle.insure(...)

    insurance.id: The id of that insure (unique within a paddle instance) insurance.paddle: The instance of Paddle insurance.error_callback: the function specified by insure insurance.args: the arguments for the error_callback insurance.timeout: The epoch time when this insurance is considered expired insurance.done: Boolean has this insurance been check_in'd

    insurance.check_in(): Delcare this insurance completed, avoiding the error_callback.

    Events

    The Paddle instance is an EventEmitter, so on(), once() etc can be used to register event callbacks.

    check_in:
    When an insurance is finished without timeout. The insurance obj is passed.

    timeout:
    When an insurance has timed-out. The insurance obj is passed.

    Examples

    Node.js famously had an http client but where occasionally no callback would occur for an HTTP request if the response was too fast. If I wanted to ensure that my http client callback occurred, I would call ensure in Paddle and check_in within the callback. As simple as that!

    var http = require('http'),
        paddle_mod = require('paddle');
    var options = {
        host: 'andyet.net',
        port: 80,
        path: '/team/nathan',
    }
    
    var paddle = new paddle_mod.Paddle(5);
    
    
    setTimeout(function() {
        paddle.stop();
    }, 12000);
    
    var req = http.get(options, function(res) {
        var http_insurance = paddle.insure(function(res) {
            console.log("The request never had body events!");
            console.log('STATUS: ' + res.statusCode);
            console.log('HEADERS: ' + JSON.stringify(res.headers));
        }, 9, [res]);
        res.setEncoding('utf8');
        res.on('data', function (chunk) {
            console.log('BODY: ' + chunk);
            http_insurance.check_in();
        });
    });
    req.end();
    

    Install

    npm i paddle

    DownloadsWeekly Downloads

    16

    Version

    1.0.0

    License

    none

    Last publish

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