0.2.5 • Public • Published


Build Status Dependency Status Coverage Status


Create a dynamic web server that generates static or dynamic responses based on json configuration.

Routes can be added dynamically through:

  • initialization config when fakr starts,
  • fakr.addRoute function if you are in the same scope
  • fakr.addCrudApi function to generate CRUD REST-ish api routes automatically
  • a restful-ish api.


var config = require('config.json'),
    fakr = require('fakr')(config);

fakr.listen(3000, function() {
  console.log('fakr is listening on port 3000');
// in the same scope, you can add route
  "url": "/api/example/(\\d+)",
  "json": {data: [1, 2, 3, 4]},

You can also extend an existing express 4.x app (since fakr 0.2 - use version 0.1.x for express 3):

var express = require('express'),
    fakr    = require('fakr'),
    // config. can be {}
    config  = require('config.json');

// get an express app
var app = express();
app.get(function(req, res) {
  res.send('original route');

// then augment the app with fakr
fakr(config, app);

// you can now add routes dynamically

  "url": "/api/example/(\\d+)",
  "json": {data: [1, 2, 3, 4]},

Note that this feature does not work yet with express 4.


  "hasAdmin": true,
  "adminUrlPrefix": "/_admin",
  defaults: {
    "headers": [
      "status": 201,
      "headers": {
        "Expires": "Fri, 17 Jan 2014 05:25:28 GMT",
        "X-Frame-Options": "SAMEORIGIN" 
  "routes": [
    ... see route configuration below...

Config options


If hasAdmin is true (see below), then adminUrl defines the API endpoint prefix url. Default: /_admin.


If true, adds the following admin API routes:

  • for managing routes:

    • one for listing routes: GET {{adminUrlPrefix}}/routes
    • one for creating new routes: POST {{adminUrlPrefix}}/routes
      • the json body should be a valid route
    • one for modifying a route: PUT {{adminUrlPrefix}}/routes
      • the json body should be a valid route
    • one for deleting routes through: DELETE {{adminUrlPrefix}}/routes
      • if the json body is not empty: the json body request should contain a url (string). method is optional (uses the config value, which defaults to get)
      • if the json body is empty: all routes will be removed!!
  • for getting previous requests when storeRequests is set to true:

    • one for getting the previous requests: GET {{adminUrlPrefix}}/routes

      • the query string should represent a valid route (url, method are mandatory, isRegExp optional)
    • one for resetting the previously stored requests: DELETE {{adminUrlPrefix}}/routes

      • the json body should be a valid route
  • for managing CRUD api routes:

    • one for listing all CRUD api routes: GET {{adminUrlPrefix}}/api-routes
    • one for getting one CRUD api route info: GET {{adminUrlPrefix}}/api-routes/{{route-name}}
    • one for creating new CRUD api routes: POST {{adminUrlPrefix}}/api-routes
    • one for deleting CRUD api routes through: DELETE {{adminUrlPrefix}}/routes


An array of routes that will be available when server starts. See below how to configure routes.

Other routes can be added dynamically after the server is started.

Route Configuration

All routes can have the following properties:

  • headers: a list of header names/headers values, like Content-type... (default: {"content-type": "application/json"}).
  • status: http response status code (default: 200).
  • url: the url, accepts regular expressions if isRegExp is true, or expressjs url format (`/route/:id...) if it is false.
  • isRegExp: tells fakr if the provided url param (as string) should be converted into a regExp (default: false).
    • note that it has no effect if url is a js regExp object.
  • method: http method (default: get)

You can also set the default values for all responses in your config, under the defaults properties.

Each route type uses different properties.

  • if it has a string property, it is a string route.
    • the stringproperty should be a string.
  • if it has a template property, it is a template route.
    • the template property should be a string that should be into a hogan.js template. The template has access to req, so req.params, req.body or req.
  • if it has a json property, it is a json route.
    • the json property should be a valid json object.
  • if it has a function property, it is a... guess what? Yes, a function route.

The order of creation of routes is important: the first matching route is executed.
Also, if a route has a string and a functionproperty (who would do that anyway?), fakr assumes that it is a string route.

String Route Example

For static response.

  "url": "/api/test-string",
  "string": "this is a string",
  "method": "get",
  "header": "text/plain",
  "status": "200"

String Route Example

For templated response, that has access to the request object property. Uses hogan.js (mustache-like)

{ "url": "/api/test-template/:id-:title",
  "isRegExp": false,
  "template": "* id is {{req.params.id}}\n" +
              "* title is {{req.params.title}}\n" +
              "* q is {{req.query.q}}\n",
  "method": "get"

When requesting GET /api/test-template/1-hello?q=yo, it will respond with:

* id is 1
* title is hello
* q is yo

JSON Route Example

This route forces the Content Type header (relies on expressjs response.json())

  "url": "/api/test-json",
  "json": {"prop1": "value1", "tags": ["news", "koko"]},
  "method": "post",
  "status": 201

Function Route Example

  "url": "/api/test-function/:resource",
  "method": "get",
  "function": "function(route) { return function(req, res, next) {res.send(req.params.resource); }}"

function can be a real function or a string to evals to a string. It should return a middleware function (params are: req, res, next (optional)).

Why not directly the middleware function? Thanks to closure, you can do things like that:

function(route) {
  var nbCalls = 0;
  return function(req, res /*, next*/) {
    var text = ++nbCalls < 3 ?
                'called ' + nbCalls + ' times':
                'stop, I\'m tired.' +
                '\nid: ' + req.params.id +
                '.\ntitle: ' + req.params.id;

You can also have access to the json route definition using route, and add extra parameter to the routedefinition and access them in the function.


You can also add CRUD routes using the fakr.addCrudApi() or the admin api url.

you need to provide a name, which is the name of the entity you want to manage. It will generate by default 5 routes per entity:

  • find url: defaults to GET /{{entity-name}} which lists all entity instances
  • get url: defaults to GET /{{entity-name}}/{{ID}} which returns one entity instance
  • add url: defaults to POST /{{entity-name}}.
    • expects a json in the request body.
  • remove url: defaults to DELETE /{{entity-name}}/{{ID}}
  • update url: defaults to PUT /{{entity-name}}/{{ID}}
    • expects a json in the request body.

All the data are kept in memory and is lost when you stop the express app.

CRUD API Configuration

To create new CRUD API, the minimum configuration is:

{ "name": "entities" }

// Generates the following urls:
// GET    /entities
// GET    /entities/ID
// POST   /entities
// DELETE /entities/ID
// PUT /entities/ID


But you have control on a lot of things if you need. Here is the default configuration:

  model: {
    config: { idKey: 'id',
              keyStrategy: 'autoIncrement',  // other strategy: 'guid'
              // if true, it will throw if you try to:
              // * add an existing id
              // * delete a non-existing id
              // * update a non-existing id
              detectExisting: false
    initData: []  // an array of entities (POJO)
  urlBase: '/{{name}}',
  routes: {
    find: {
      // each route should be a valid route as described in `route configuration` section,
      // except for the funtion url that should follow the structure below 
      // (a function with param status and model that returns a function 
      // that returns a function with params request et reponse... yeah... I know...)
      method: 'get',
      url: '{{urlbase}}',
      function: function(status, model) {
        return function() {
          return function(req, res) {
            res.json(status, {data: model.getAll()});
    get: {
      method: 'get',
      url: '{{urlbase}}/:id',
      function: function(status, model) {
        return function() {
          return function(req, res) {
            var item = model.findById(req.params.id);
            if (item === undefined) {
              return res.json(404, {});
            res.json(status, model.findById(req.params.id));
    add: {
      method: 'post',
      url: '{{urlbase}}',
      status: 201,
      function: function(status, model) {
        return function() {
          return function(req, res) {
            res.json(status, {data: model.add(req.body) });
    remove: {
      method: 'delete',
      url: '{{urlbase}}/:id',
      function: function(status, model) {
        return function() {
          return function(req, res) {
            res.json(status, {data: model.remove(req.params.id) });
    update: {
      method: 'put',
      url: '{{urlbase}}/:id',
      function: function(status, model) {
        return function() {
          return function(req, res) {
            res.json(status, {data: model.update(req.params.id, req.body) });

In the url properties, {{urlbase}} and {{name}} are replaced by the name and urlBase.

If you don't want one of the 5 generated urls, just assign falseto the corresponding route in the config.

Public API

fakr(config, app)

config is a json configuration, it can be null, defaults to {}.

app is optional. If defined, it should be an expressjs app. It will


Adds a route defined in json(see Route configuration)

Note that if fakr() was called with an app param, then adding a fakr route that match exactly a already existing app route will have no effect: the original route will match.

If 2 fakr routes have the same url and method, then the last defined route will overwite the first route.


remove a route defined in json. Expected json.url. json.method (or default method) is used to find the route that will be deleted.


remove all routes added by fakr.

If fakr() was called with an app param, then only routes added through config, app.addRoute() or the adminapi will be deleted.


Adds CRUD API routes. config should contain a name property. See above the CRUD API Configuration.


Removes CRUD API routes.


In case you need to debug something...


array of fakr routes (added through init config, addRoutes or api calls).


list of CRUD API routes. the key is the name of the CRUD API routes.


It is not added by fakr library, but it is an express property. fakr uses it when removing routes. Helpful to debug.


  • add grunt
  • add tests
  • add regExp url format support (through new RegExp()?)
  • add CRUD route type
  • add API to control routes dynamically
  • add API to control api routes dynamically
  • add an admin UI
  • add way to "prepare the future" (first call: return this once, then this 3 times, or a la sinonjs...)





  • upgraded packages


  • upgraded packages


  • upgraded packages


  • upgraded packages


  • upgraded to express 4


  • added access to route (json) in function route


  • added simple request logger (to console)


  • added crud api routes (list, get, add and delete)


  • fakr can extend existing express app by adding addRoutes, admin api...


  • added removeAllRoutes and corresponding /_admin/routes DELETE api (with no params!!)
  • add PUT method to update a route


  • fixed npm main property and hoganjs dependency

Package Sidebar


npm i fakr

Weekly Downloads






Last publish


  • saadtazi