Panda

Panda is an mvc framework built with Ruby for building web applications.

Getting started

Clone Panda

$ git clone https://github.com/akabiru/panda

Add this line to your application’s Gemfile:

gem 'panda_frwk'

And then execute:

$ bundle

Usage

Panda uses the mvc pattern. Thus your application structure should be as follows:

.
├── app
│   ├── controllers
│   │   └── todo_controller.rb
│   ├── models
│   │   └── todo.rb
│   └── views
│       ├── layouts
│       │   └── application.html.erb
│       └── todo
│           ├── edit.html.erb
│           ├── index.html.erb
│           ├── new.html.erb
│           └── show.html.erb
├── config
│   ├── application.rb
│   └── routes.rb
├── config.ru
├── db
│   └── app.db
├── Gemfile
├── Gemfile.lock
└── README.md

Routes

Your routes should be defined in config/routes.rb file. Here’s an example.

TodoApplication.routes.draw do
  root "todo#index"
  get "/todo", to: "todo#index"
  get "/todo/new", to: "todo#new"
  get "/todo/:id", to: "todo#show"
  get "/todo/:id/edit", to: "todo#edit"
  post "/todo", to: "todo#create"
  put "/todo/:id", to: "todo#update"
  delete "/todo/:id", to: "todo#destroy"
end

Models

Models are defined in app/models folder. Here’s an example model

class Todo < Panda::Record::Base
  to_table :todos
  property :id, type: :integer, primary_key: true
  property :title, type: :text, nullable: false
  property :body, type: :text, nullable: false
  property :status, type: :text, nullable: false
  property :created_at, type: :text, nullable: false
  create_table
end

Controllers

Controllers are defined in app/controllers. Here’s an example controller.

class TodoController < Panda::BaseController
  def index
    @todos = Todo.all
  end

  def show
    @todo = Todo.find(params["id"])
  end

  def new
  end

  def edit
    @todo = Todo.find(params["id"])
  end

  def update
    todo = Todo.find(params["id"])
    todo.update(
      title: params["title"],
      body: params["body"],
      status: params["status"]
    )
    redirect_to "/todo/#{todo.id}"
  end

  def create
    Todo.create(
      title: params["title"],
      body: params["body"],
      status: params["status"],
      created_at: Time.now.to_s
    )
    redirect_to "/todo"
  end

  def destroy
    todo = Todo.find(params["id"])
    todo.destroy
    redirect_to "/todo"
  end
end

Views

Views are mapped to the controller actions. E.g if You have a TodoController, views for that controller should be defined in app/views/todos/action_name.erb. Panda depends on Tilt gem and thus supports embedded ruby in the views. Instance variables defined in the controller actions can be accessed in the corresponding view.

Here’s an example usage:

Controller app/controllers/todo_controller.rb

[...]
def index
  @todos = Todo.all
end
[...]

View app/views/index.html.erb

<h1>My Todos</h1>

<% @todos.each do |todo| %>
  <p><strong><%= todo.title %></strong> <em><%= todo.status %></em>
    <a href="/todo/<%= todo.id %>" id="todo_<%= todo.id %>">Show</a> | <a href="/todo/<%= todo.id %>/edit">Edit</a>
  </p>
<% end %>

<p><a href="/todo/new">New Todo</a></p>

Note that there’s an layout file app/views/layouts/application.html.erb. Here you can define your general view layout. Other views will be rendered inside the file.

Here’s a sample layout file:

<!DOCTYPE html>
<html>
<head>
  <title><%= title %></title>
</head>
<body>
  <%= yield %>
</body>
</html>

Configuration

I bet you’ve noticed that there’s a config.ru file. This file that gets called when we run our panda application. However, there’re some few things to take note of:

Set the APP_ROOT to the current directory since panda uses that constant to find templates.

APP_ROOT = __dir__

Require config/appliaction

require_relative './config/application.rb'

Add method override middleware. This masks put and delete request as post requests.

use Rack::MethodOverride

After this what’s left is initialising the panda application, locading the routes and running it.

To run the application run

$ bundle exec rackup

at the root of your application.

Tests

Panda is well tested with a sample application for integration tests and unit specs for the base model. To run the specs run

$ bundle exec rake

$ bundle exec rspec -fd

Application Limitations

Panda does not have a generator for file structures.
Panda does not support model relationships at the moment

Dependencies

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/akabiru/panda. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.

License

The gem is available as open source under the terms of the MIT License.