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    0.2.4 • Public • Published

    grunt-connect-delay Build Status

    A delay proxy middleware for grunt-contrib-connect

    This plugin provides a delay middleware for Grunt Connect / Express. It can be used for introducing artificial delays before proxying certain URLs based on RegExp rules.

    By default, it includes the rule that any URL which matches the pattern ^/delay/([0-9]+)/(.*)$ will be delayed by $1 milliseconds and be redirected to /$2.

    Hence, to check your app's behavior when a particular request is slow, just prefix /delay/5000/ to the URL.

    Getting started

    This plugin requires Grunt ~0.4.1

    If you haven't used Grunt before, be sure to check out the Getting Started guide, as it explains how to create a Gruntfile as well as install and use Grunt plugins.

    npm install grunt-connect-delay --save-dev



    Type: Boolean

    Default Value: true

    This adds the following default rule to the configuration:

    { rule    : '/delay/([0-9])+/(.*)$'
    , delay   : '$1'
    , rewrite : '/$2'

    This means that to delay a link, you only need to prefix it with /delay/:milliseconds/<original URL>. grunt-connect-delay will wait for the said number of milliseconds before proceeding to the <original URL>


    Type: String

    Default value: connect.delay

    This is the section in the Gruntfile from where the delay rules will be read.

    Simple rule format

    {url: 'FROM', delay: MILLISECONDS }


    • FROM: RegExp string to match
    • MILLISECONDS: The delay in milliseconds to introduce before proceeding with proxying
    Extended rule format

    {url: 'FROM_REGEXP', delay: 'NUMBER_OR_REPLACEMENT', rewrite: 'REPLACEMENT' }


    • FROM_REGEXP: RegExp string to match the URL and create groups to be used for deducing delay and the true proxied URL. e.g. ^/delay/([0-9]*)/(.*)$.
    • NUMBER_OR_REPLACEMENT: The number of milliseconds (e.g. 1000) to wait or a string which can be parsed to an integer after a URL (which matches url) is replaced by it (e.g. $1).
    • REPLACEMENT: A string which maps to the destination URL after a URL is replaced by it (e.g. /$2).


    In your project's Gruntfile:

    • Include the delayRequest snippet: var delayRequest = require('grunt-connect-delay/lib/utils').delayRequest.
    • Load the plugin: grunt.loadNpmTasks('grunt-connect-delay')
    • Add configureDelayRules before the web server task.

    Optional (advanced usage):

    • Configure options in configureDelayRules.options in initConfig, or,
    • Add a section named delay to your existing Connect definition

    To see some logs about the proxying, use the --verbose flag while running grunt.

    var delayRequestSnippet = require('grunt-connect-delay/lib/utils').delayRequest;
        connect: {
            delay: [
                { url: '^/api/.*$', delay: 10000 } // Delay calls to API by 10sec
            dev: {
                options: {
                    middleware: function (connect, options, middlewares) {
                        return middlewares;
                        // Old style:
                        // See:
                        // return [
                        //        delayRequestSnippet
                        //      , rewriteRequestSnippet
                        //      , proxyRequestSnippet
                        //      , connect.static(path.resolve(dir))
                        // ];
        /* Optional */
        configureDelay: {
            options: {
                rulesProvider  : 'connect.delay'
              , useDefaultRule : true
    // "configureDelayRules" should be before the "connect"/"express" task
    grunt.registerTask('server', function (target) {[

    Though I haven't tested it, it should work in a similar fashion with grunt-express task as well.

    You can see how to use this plugin at musically-ut/grunt-connect-delay-example.


    The structure and documentation of this plugin is inspired by grunt-connect-rewrite plugin.

    Release Notes

    • 0.2.3: Update usage instuctions
    • 0.2.2: Bump version to resolve npm bug
    • 0.2.1: Improve documentation
    • 0.2.0: Add extended rules and a default rule
    • 0.1.1: Improve logging
    • 0.1.0: Initial release


    npm i grunt-connect-delay

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