Raamen

Raamen is a Rack and SQLite based MVC web framework. It contains modules to provide basic and necessary features of web app components as well as helpful Rack middleware, cookie manipulation, and CLI to make the development process faster and easier.

contents

  • SQLObject
  • ControllerBase
  • Routing
  • Cookies
  • Middleware
  • Command Line Interface

Installation

Add this line to your application's Gemfile:

gem 'raamen'

And then execute:

$ bundle

Or install it yourself as:

$ gem install raamen

Usage

SQLObject

class Cat < Raamen::SQLObject
  belongs_to :owner,
    class_name: 'Human',
    foreign_key: :owner_id

  self.finalize!
end

ControllerBase

class CatsController < Raamen::ControllerBase
  def index
    @cats = Cat.all
    render :index
  end

  def new
    @cat = Cat.new
    render :new
  end

  def create
    cat = Cat.new(cat_params)
    cat.save
    redirect_to '/cats'
  end

  private

  def cat_params
    params['cat']
  end
end

Routing

router = Raamen::Router.new
router.draw do
  get Regexp.new("^/cats$"), CatsController, :index
  get Regexp.new("^/cats/new$"), CatsController, :new
  post Regexp.new("^/cats$"), CatsController, :create
end

Cookies

class MyController < ControllerBase
  def go
    session["count"] ||= 0
    session["count"] += 1
    render :counting_show
  end
end


class DogsController < ControllerBase
  def create
    @dog = Dog.new(params["dog"])
    if @dog.save
      flash[:notice] = "Saved dog successfully"
      redirect_to "/dogs"
    else
      flash.now[:errors] = @dog.errors
      render :new
    end
  end
end

Middleware

app = Rack::Builder.new do
  use Raamen::ShowExceptions
  use Raamen::Static
  run app
end.to_app

Command Line Interface

To start a new project:

$ raamen n/new cats

To generate a new component:

$ raamen g/generate controller CatsController

To start server:

$ raamen s/start

To start console:

$ raamen c/console

Implementation

SQLObject modules:

module Associatable
  def belongs_to(name, options = {})
    self.assoc_options[name] = BelongsToOptions.new(name, options)

    define_method(name) do
      options = self.class.assoc_options[name]
      key_val = self.send(options.foreign_key)
      options.model_class.where(options.primary_key => key_val).first
    end
  end

  def has_many(name, options = {})
    self.assoc_options[name] = HasManyOptions.new(name, self.name, options)

    define_method(name) do
      options = self.class.assoc_options[name]
      key_val = self.send(options.primary_key)
      options.model_class.where(options.foreign_key => key_val)
    end
  end
end

module Searchable
  def where(params)
    where_line = params.keys.map do |col|
      "#{col}= ?"
    end.join(" AND ")

    parse_all(DBConnection.execute(<<-SQL, *params.values))
      SELECT
        *
      FROM
        #{self.table_name}
      where
        #{where_line}
    SQL
  end
end

Template rendering:

def render_content(content, content_type)
  raise "double render" if already_built_response?
  self.res["Content-Type"] = content_type
  self.res.write(content)
  self.session.store_session(res)
  self.flash.store_flash(res)
  self.already_built_response = true
end

def render(template_name)
  template_path = File.join(
    Dir.pwd,
    "app",
    "views",
    "#{self.class.name.underscore}",
    "#{template_name}.html.erb"
    )
  template_content = File.read(template_path)
  render_content(ERB.new(template_content).result(binding), "text/html")
end

Redirecting:

def redirect_to(url)
  raise "double render" if already_built_response?
  self.res["location"] = url
  self.res.status = 302
  self.session.store_session(res)
  self.flash.store_flash(res)
  self.already_built_response = true
end

Cross-Site Request Forgery protection:

def form_authenticity_token
  self.res.set_cookie(
    "authenticity_token",
    {path: "/", value: self.authenticity_token}
  )
  self.authenticity_token
end

def self.protect_from_forgery
  @@protect_from_forgery = true
end

private

def generate_authenticity_token
  SecureRandom.urlsafe_base64(16)
end

def check_authenticity_token
  cookie = self.req.cookies["authenticity_token"]
  unless cookie && cookie == params["authenticity_token"]
    raise "Invalid authenticity token"
  end
end

Adding new routes:

def add_route(pattern, method, controller_class, action_name)
  self.routes.push(Route.new(pattern, method, controller_class, action_name))
end

def draw(&proc)
  self.instance_eval(&proc)
end

[:get, :post, :put, :delete].each do |http_method|
  define_method(http_method) do |pattern, controller_class, action_name|
    add_route(pattern, http_method, controller_class, action_name)
  end
end

Flash cookies:

class Flash
  attr_reader :flash, :now

  def initialize(req)
    flash = req.cookies["_rails_lite_app_flash"]
    @now = flash ? Now.new(JSON.parse(flash)) : Now.new({})
    @flash = {}
  end

  def [](key)
    self.now[key.to_sym] || self.flash[key.to_sym]
  end

  def []=(key, val)
    self.flash[key.to_sym] = val
  end

  def store_flash(res)
    res.set_cookie("_rails_lite_app_flash", {path: "/", value: self.flash.to_json})
  end
end

Sesssion Cookies:

class Session
  attr_reader :cookies

  def initialize(req)
    cookies = req.cookies["_rails_lite_app"]
    cookies = Hash[JSON.parse(cookies).map{ |k,v| [k.to_sym, v] }] if cookies
    @cookies = cookies || {}
  end

  def [](key)
    self.cookies[key.to_sym]
  end

  def []=(key, val)
    self.cookies[key.to_sym] = val
  end

  def store_session(res)
    res.set_cookie("_rails_lite_app", {path: "/", value: self.cookies.to_json})
  end
end

Show exceptions middleware:

class ShowExceptions
  attr_reader :app

  def initialize(app)
    @app = app
  end

  def call(env)
    begin
      self.app.call(env)
    rescue Exception => e
      render_exception(e)
    end
  end
end

Static assets middleware:

class Static
  attr_reader :app, :root, :file_server

  def initialize(app)
    @app = app
    @root = :public
    @file_server = FileServer.new(self.root)
  end

  def call(env)
    req = Rack::Request.new(env)
    path = req.path

    if path.include?("/#{self.root}")
      res = self.file_server.call(env)
    else
      res = self.app.call(env)
    end

    res
  end
end

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/[USERNAME]/raamen. 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.