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Class: YARD::Server::Commands::Base Abstract

Relationships & Source Files
Extension / Inclusion / Inheritance Descendants
Subclasses:
DisplayFileCommand, DisplayObjectCommand, FramesCommand, LibraryCommand, LibraryIndexCommand, ListCommand, RootRequestCommand, SearchCommand, StaticFileCommand
Inherits: Object
Defined in: lib/yard/server/commands/base.rb

Overview

This class is abstract.

This is the base command class used to implement custom commands for a server. A command will be routed to by the ::YARD::Server::Router class and return a Rack-style response.

Attribute Initializers

All attributes can be initialized via options passed into the #initialize method. When creating a custom command, the Adapter#options will automatically be mapped to attributes by the same name on your class.

class MyCommand < Base attr_accessor :myattr end

Adapter.new(libs, => 'foo').start

# when a request comes in, cmd.myattr == 'foo'

Subclassing Notes

To implement a custom command, override the #run method, not #call. In your implementation, you should set the body and status for requests. See details in the #run method documentation.

Note that if your command deals directly with libraries, you should consider subclassing the more specific LibraryCommand class instead.

See Also:

Since:

  • 0.6.0

Basic Command and Adapter Options

Attributes Set Per Request

Instance Method Summary

Abstract Methods

  • #run ⇒ void abstract

    Subclass this method to implement a custom command.

Helper Methods

  • #add_cache_control private

    Add a conservative cache control policy to reduce load on requests served with "?1234567890" style timestamp query strings.

Constructor Details

.new(opts = {}) ⇒ Base

Creates a new command object, setting attributes named by keys in the options hash. After initialization, the options hash is saved in #command_options for further inspection.

Examples:

Creating a Command

cmd = DisplayObjectCommand.new(:caching => true, :library => mylib)
cmd.library # => mylib
cmd.command_options # => {:caching => true, :library => mylib}

Parameters:

  • opts (Hash) (defaults to: {}) —

    the options hash, saved to #command_options after initialization.

Since:

  • 0.6.0

[ GitHub ] 

  


# File 'lib/yard/server/commands/base.rb', line 75



def initialize(opts = {})
  opts.each do |key, value|
    send("#{key}=", value) if respond_to?("#{key}=")
  end
  self.command_options = opts
end


  







Instance Attribute Details



  

    #adapter  ⇒ Adapter  (rw)
  



  

    
  





  
Returns:



Since:


    
  
  • 
    
    0.6.0
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/yard/server/commands/base.rb', line 41



attr_accessor :adapter


  








  

    #body  ⇒ String  (rw)
  



  

    
  





  
Returns:


    
  
  • 
    (String)
—    
    the response body. Defaults to empty string.
    

    
  
    • 



Since:


    
  
  • 
    
    0.6.0
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/yard/server/commands/base.rb', line 61



attr_accessor :body


  








  

    #caching  ⇒ Boolean  (rw)
  



  

    
  





  
Returns:


    
  
  • 
    (Boolean)
—    
    whether to cache
    

    
  
    • 



Since:


    
  
  • 
    
    0.6.0
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/yard/server/commands/base.rb', line 44



attr_accessor :caching


  








  

    #command_options  ⇒ Hash  (rw)
  



  

    
  





  
Returns:


    
  
  • 
    (Hash)
—    
    the options passed to the command's constructor
    

    
  
    • 



Since:


    
  
  • 
    
    0.6.0
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/yard/server/commands/base.rb', line 38



attr_accessor :command_options


  








  

    #headers  ⇒ Hash{String => String}  (rw)
  



  

    
  





  
Returns:



Since:


    
  
  • 
    
    0.6.0
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/yard/server/commands/base.rb', line 55



attr_accessor :headers


  








  

    #path  ⇒ String  (rw)
  



  

    
  





  
Returns:


    
  
  • 
    (String)
—    
    the path after the command base URI
    

    
  
    • 



Since:


    
  
  • 
    
    0.6.0
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/yard/server/commands/base.rb', line 52



attr_accessor :path


  








  

    #request  ⇒ Rack::Request  (rw)
  



  

    
  





  
Returns:



Since:


    
  
  • 
    
    0.6.0
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/yard/server/commands/base.rb', line 49



attr_accessor :request


  








  

    #status  ⇒ Numeric  (rw)
  



  

    
  





  
Returns:


    
  
  • 
    (Numeric)
—    
    status code. Defaults to 200 per request
    

    
  
    • 



Since:


    
  
  • 
    
    0.6.0
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/yard/server/commands/base.rb', line 58



attr_accessor :status


  







Instance Method Details



  

    #add_cache_control   (private)
  



  

    
Add a conservative cache control policy to reduce load on
requests served with "?1234567890" style timestamp query strings.


  





  
Since:


    
  
  • 
    
    0.6.0
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/yard/server/commands/base.rb', line 202



def add_cache_control
  return if request.query_string.to_i == 0
  headers['Cache-Control'] ||= 'public, max-age=300'
end


  








  

    #call(request)  ⇒ Array(Numeric,Hash,Array<String>) 
  



  

    
  

    Note:
    
This command should not be overridden by subclasses. Implement
the callback method #run instead.



  



The main method called by a router with a request object.


  





  
Parameters:


    
  
  • 
    request
    (Adapter Dependent)
—    
    the request object
    

    
  
    • 



Returns:


    
  
  • 
    (Array(Numeric,Hash,Array<String>))
—    
    a Rack-style response
of status, headers, and body wrapped in an array.
    

    
  
    • 



Since:


    
  
  • 
    
    0.6.0
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/yard/server/commands/base.rb', line 89



def call(request)
  self.request = request
  self.path ||= request.path_info[1..-1]
  self.headers = {'Content-Type' => 'text/html'}
  self.body = ''
  self.status = 200
  add_cache_control
  begin
    run
  rescue FinishRequest
    nil # noop
  rescue NotFoundError => e
    self.body = e.message if e.message != e.class.to_s
    not_found
  end

  # keep this to support commands setting status manually.
  not_found if status == 404

  [status, headers, body.is_a?(Array) ? body : [body]]
end


  








  

    #run  ⇒ void 
  



  

    

  This method is abstract.
  




This method returns an undefined value.
Subclass this method to implement a custom command. This method
should set the #status and #body, and optionally modify the
#headers. Note that #status defaults to 200.


  





    

    
Examples:

        
A custom command



      
class ErrorCommand < Base
  def run
    self.body = 'ERROR! The System is down!'
    self.status = 500
    self.headers['Content-Type'] = 'text/plain'
  end
end

  


Raises:


    
  
  • 
    (NotImplementedError)
  
    • 



Since:


    
  
  • 
    
    0.6.0
    

    
  
    • 





  [ GitHub ]


  

  


# File 'lib/yard/server/commands/base.rb', line 128



def run
  raise NotImplementedError
end