Geddy web framework for Node.js

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Goals

• Easy to use
• Modular
• Fast

Geddy should make things easy for the most basic applications, but still let you get under the hood and tinker if you want.

Features

• Powerful, flexible router
• Easy resource-based routing
• App and resource generators
• Content-negotiation
• Session support (in-memory and CouchDB)
• Templating (EJS), partials support
• Fully non-blocking

License

Apache License, Version 2

Community

IRC:

#node.js on freenode.net

Mailing list:

http://groups.google.com/group/geddy

Building and installing Geddy

** Prerequisites**

Geddy requires version 0.1.98 of Node.js.

To get Geddy from GitHub and install it:

git clone git://github.com/mde/geddy.git
cd geddy
make && sudo make install

Routes

Routes are similar to Merb or Rails routes.

Basic routes

router.match('/moving/pictures/:id').to(
  {controller: 'Moving', action: 'pictures'});

router.match('/farewells/:farewelltype/kings/:kingid').to(
   {controller: 'Farewells', action: 'kings'});

//Can also match specific HTTP methods only
router.match('/xandadu', 'get').to(
  {controller: 'Xandadu', action: 'specialHandler'});

Resource-based routes

router.resource('hemispheres');

Creating a Geddy app

Geddy comes with a utility called geddy-gen you can use to create an app. Run geddy to start the server.

mde@localhost:~/work$ geddy-gen app bytor
Created app bytor.
mde@localhost:~/work$ cd bytor
mde@localhost:~/work/bytor$ geddy
Server running at http://127.0.0.1:4000/

Go to http://localhost:4000/, and you should see:

Attention all planets of the Solar Federation

Adding resources

Use geddy-gen resource in your app directory to add a resource. The route will be set up automatically for you.

mde@localhost:~/work/bytor$ geddy-gen resource snow_dog
[ADDED] ./app/models/snow_dog.js
[ADDED] ./app/controllers/snow_dogs.js
resources snow_dogs route added to ./config/router.js
Created view templates.

Restart Geddy, and you'll see the new route working. Hit your new route -- for example, http://localhost:4000/snow_dogs.json, and you should see something like this:

{"method":"index","params":{"extension":"json"}}

The geddy-gen utility doesn't handle fancy pluralization between model and controller -- the default is simply to add an "s" to your resource name to use for the plural in controller names and paths.

However, you can specify different singular/plural names when generating your resource. Separate the singular and plural names by a comma, like this:

mde@localhost:~/work/bytor$ geddy-gen resource person,people
[ADDED] ./app/models/person.js
[ADDED] ./app/controllers/people.js
resources people route added to ./config/router.js
Created view templates.

App layout

After adding a resource, a Geddy app is laid out like this:

mde@localhost:~/work/bytor$ find .
.
./config
./config/config.js
./config/router.js
./app
./app/controllers
./app/controllers/snow_dogs.js
./app/controllers/main.js
./app/controllers/application.js
./app/views
./app/views/snow_dogs
./app/views/snow_dogs/show.html.ejs
./app/views/snow_dogs/add.html.ejs
./app/views/snow_dogs/index.html.ejs
./public

Resources and controllers

Geddy's resource-based routes create url/request-method mappings for easy CRUD operations like this:

GET */snow_dogs[.extension]
(SnowDogs controller, index action)

GET */snow_dogs/add[.extension]
(SnowDogs controller, add action, for any new-resource template -- "new" is not usable as a JavaScript action name)

POST */snow_dogs[.extension]
(SnowDogs controller, create action)

GET */snow_dogs/:id[.extension]
(SnowDogs controller, show action)

GET */snow_dogs/:id/edit[.extension]
(SnowDogs controller, edit action)

PUT */snow_dogs/:id[.extension]
(SnowDogs controller, update action)

DELETE */snow_dogs/:id[.extension]
(SnowDogs controller, remove action)

A simple controller that just responds with any form-post/query-string params looks like this:

var SnowDogs = function () {
  this.respondsWith = ['text', 'json', 'html'];

  this.index = function (params) {
    this.respond({params: params});
  };

  this.add = function (params) {
    this.respond({params: params});
  };

  this.create = function (params) {
    this.respond({params: params});
  };

  this.show = function (params) {
    this.respond({params: params});
  };

  this.update = function (params) {
    this.respond({params: params});
  };

  this.remove = function (params) {
    this.respond({params: params});
  };

};

exports.SnowDogs = SnowDogs;

Content-negotiation

Geddy has built-in ability to perform content-negotiation based on the requested filename-extension.

If you have a JSON-serializable JavaScript object you want to return in JSON format, pass your JavaScript object to the respond method in the action on that controller.

this.respondsWith = ['text', 'json'];

this.show = function (params) {
  // (Fetch some item by params.id)
    item = {foo: 'FOO', bar: 1, baz: false};
      this.respond(item);
};

Models and validations

Geddy has an easy, intuitive way of defining models, with a full-featured set of data validations. The syntax is very similar to models in Ruby's ActiveRecord or DataMapper.

The model module is coded with browser-based use in mind, so it's very easy to share model and input validation code in your app between client and server.

Here is an example of a model with some validations:

var User = function () {
  this.property('login', 'string', {required: true});
  this.property('password', 'string', {required: true});
  this.property('lastName', 'string');
  this.property('firstName', 'string');

  this.validatesPresent('login');
  this.validatesFormat('login', /[a-z]+/, {message: 'Subdivisions!'});
  this.validatesLength('login', {min: 3});
  this.validatesConfirmed('password', 'confirmPassword');
  this.validatesWithFunction('password', function (s) {
      // Something that returns true or false
      return s.length > 0;
  });

  // Can define methods for instances like this
  this.someMethod = function () {
    // Do some stuff
  };
};

// Can also define them on the prototype
User.prototype.someOtherMethod = function () {
  // Do some other stuff
};

// Server-side, commonjs
exports.User = User;
// Client-side
// geddy.model.registerModel('User');

Creating an instance of one of these models is easy:

var params = {
  login: 'alex',
  password: 'lerxst',
  lastName: 'Lifeson',
  firstName: 'Alex'
};
var user = User.create(params);

Data-validation happens on the call to create, and any validation errors show up inside an errors property on the instance, keyed by field name. Instances have a valid method that returns a Boolean indicating whether the instance is valid.

// Leaving out the required password field
var params = {
  login: 'alex',
};
var user = User.create(params);

// Prints 'false'
sys.puts(user.valid());
// Prints 'Field "password" is required'
sys.puts(user.errors.password);

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Geddy Web-app development framework copyright 2112 mde@fleegix.org.