Class: Rubylet::Servlet

Inherits:
Object
  • Object
show all
Includes:
Java::JavaxServlet::Servlet
Defined in:
lib/rubylet/servlet.rb

Overview

Implements the Servlet API in Ruby as a Rack server.

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#app ⇒ Object (readonly)

Returns the value of attribute app.



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# File 'lib/rubylet/servlet.rb', line 9

def app
  @app
end

#context ⇒ Object (readonly)

Returns the value of attribute context.



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# File 'lib/rubylet/servlet.rb', line 9

def context
  @context
end

#servlet_config ⇒ Object (readonly)

Returns the value of attribute servlet_config.



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# File 'lib/rubylet/servlet.rb', line 9

def servlet_config
  @servlet_config
end

Instance Method Details

#destroy ⇒ Object 



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# File 'lib/rubylet/servlet.rb', line 41

def destroy
  # no-op
end

#init(servletConfig) ⇒ Object

Parameters:

  • servletConfig (javax.servlet.ServletConfig) 


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# File 'lib/rubylet/servlet.rb', line 12

def init(servletConfig)
  @servlet_config = servletConfig
  @context = servletConfig.getServletContext
  
  rackup_file = param('rubylet.rackupFile') || 'config.ru'
  @app, _opts = Rack::Builder.parse_file(rackup_file)

  if defined?(Rails) && defined?(Rails::Application) && (@app < Rails::Application)
    servlet_path = @servlet_config.getInitParameter('rubylet.servletPath')
    relative_root = if servlet_path 
                      File.join(@context.context_path, servlet_path)
                    else
                      @context.context_path
                    end
    app.config.action_controller.relative_url_root = relative_root
    ActionController::Base.config.relative_url_root = relative_root
  end
end

#param(name) ⇒ Object

def param(config, name)

config.getInitParameter(name) ||
  config.getServletContext.getInitParameter(name)

end



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# File 'lib/rubylet/servlet.rb', line 36

def param(name)
  @servlet_config.getInitParameter(name) ||
    @servlet_config.getServletContext.getInitParameter(name)
end

#service(req, resp) ⇒ Object

assumed to be an HttpServletRequest

assumed to be an HttpServletResponse

Parameters:

  • req (javax.servlet.ServletRequest) —

    a Java servlet request,

  • resp (javax.servlet.ServletResponse) —

    a Java servlet response



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# File 'lib/rubylet/servlet.rb', line 56

def service(req, resp)
  env = Environment.new(req, self)
  
  catch(:async) do
    status, headers, body = app.call(env)  # may throw async
    throw :async if status == -1  # alternate means of indicating async
    respond(resp, env, status, headers, body)
    return  # :async not thrown
  end

  # :async was thrown; this only works since Servlet 3.0
  # web.xml must also have <async-supported>true<async-supported> in
  # all servlets and filters in the chain.
  #
  # TODO: this works in proof-of-concept! anything more todo?
  #
  # TODO: Rack async doesn't seem to be standardized yet... In particular,
  # Thin provides an 'async.close' that (I think) can be used to
  # close the response connection after streaming in data asynchronously.
  # For now, this code only allows a one-time deferal of the body (i.e.
  # when 'async.callback' is called, the body is sent out and the
  # connection closed immediately.)
  #
  # TODO: because of the above, there isn't a way to quickly send headers
  # but then delay the body.
  #
  # Example Rack application:
  #
  #    require 'thread'
  #
  #    class AsyncExample
  #      def call(env)
  #        cb = env['async.callback']
  #
  #        Thread.new do
  #          sleep 5                # long task, wait for message, etc.
  #          body = ['Hello, World!']
  #          cb.call [200, {'Content-Type' => 'text/plain'}, body]
  #        end
  #
  #        throw :async
  #      end
  #    end
  async_context = req.startAsync
  env.on_async_callback do |(status, headers, body)|
    resp = async_context.getResponse
    respond(resp, env, status, headers, body)
    async_context.complete
  end
end

#to_s ⇒ Object Also known as: servlet_info 



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# File 'lib/rubylet/servlet.rb', line 45

def to_s
  "#<#{self.class} @app=#{@app}>"
end