libfalcon-engine1 0.9.6.9-git20120606-2.1+b1 / usr / lib / falcon / web / oauth2.fal

/*
   FALCON - The Falcon Programming Language.
   OAuth2 authentication scheme support - main file

   FILE: oauth2.fal

   Main module file
   -------------------------------------------------------------------
   Author: Greta Carenzo
   Begin: Mon, 21 Jun 2010 13:38:47 +0200

   -------------------------------------------------------------------
   (C) Copyright 2010: the FALCON developers (see list in AUTHORS file)

   See LICENSE file for licensing details.
*/

import from hash
import from curl
import from json
import from web.oauth

// repeat common enums
import UseHeader from web.oauth as UseHeader
import Via from web.oauth as Via
export UseHeader, Via

/*#
   @main Support for OAuth 2.0 protocol.

   This modules code to establish OAuth sessions under the 2.0 protocol.

   OAuth is a cross-site authentication exchange protocol
   used in Web2.0 development.

   @note The module depends on Feathers @a hash module and on
   the optional @a curl module. This module also depends from
   @a web.oauth
*/



/*# Interface to remote OAuth2 authentication process server.
   @param consumer_key The consumer key identifying the requester on the remote OAuth2 server.
   @optparam mode One of the @a Via methods (Defaults to POST).

   This class acts as an authentication client connecting with a
   remote server.
*/
class Client( cust_id, cust_secret, mode ) from web.oauth.Client( cust_id, cust_secret, mode )

   //# OAuth protocol is 2.0 here.
   version = "2.0"

   /*# Perform a token request.
      @param address The address of the remote token provider.
      @param callback Address to be called back by authenticator if the caller is of a web application.
      @param code A code received calling the authorize uri.
      @return A new @a Token created through this call.
      @raise ProtoError if the remote side doesn't complain with the OAuth protocol.

      This method requests an "Access token" the remote OAuth service.

      For example, a theoretic workflow may be

      @code
      import from web.oauth in oauth

      code = Reply.redirect("https://TheRemoteService/oauth/authorize",0)

      //the GET parameters that must be passed are: client_id and redirect_uri.

      //An important thing is that the redirect_uri and the callback parameter passed in the getToken function must be the same!

      client = oauth.Client( "MyClientID", "MyClientSecret" )
      access_token = client.getToken( "https://TheRemoteService/oauth/access_token", callback,code )

      userData = client.callAPI( access_token,
                  "https://TheRemoteService/get_user",
                  ["user_id"=> my_user_id] )

      @endcode

      @note This method blocks until the remote side replies.
   */
   function getToken( address, callback, code)


      paramsB = self._makeBaseParams()

      paramsB["grant_type"] = "authorization_code"
      paramsB["code"] = code

      if callback: paramsB[ "redirect_uri" ] = callback

      cr = self.makeOAuthHandler( address, paramsB, nil )
      cr.setOutString()
      cr.exec()
      data = cr.getData()

      try
         dt = self.parseQS( data )
      catch ParamError
         raise web.oauth.ProtoError( 10001, i"Invalid answer from remote.", data )
      end

      if not "access_token" in dt
         raise web.oauth.ProtoError( 10002, i"Response didn't contain an oauth_token", data )
      end

      token = web.oauth.Token( dt["access_token"] )

      return token
   end


   //==========================================================
   // API utilities
   //==========================================================

   /*# Call an API protected by OAuth.
      @param token An instance of @a Token.
      @param uri The URI of the remote OAuth protected Web API to be called.
      @optparam params Optional parameters for the call.
      @return The raw data returned by the remote OAuth procedure.

      Calls a remote web API and blocks until a result is available.
   */
   function callAPI( token, uri, params )

      oauth_params = self._makeBaseParams()
      oauth_params["access_token"] = token

      cr = self.makeOAuthHandler( uri, oauth_params, params )

      cr.setOutString()
      cr.exec()
      data = json.JSONdecode(cr.getData())

      if "error" in data
      	   raise web.oauth.ProtoError(10004,data["error"]["message"],nil)
      end

      return data
   end

   //# @ignore
   function makeOAuthHandler( address, oauth_params, params )
      // Create the base string.
      if params
         all_params = oauth_params + params
      else
         all_params = oauth_params
      end

      base_fields = self._makeGet( all_params )
      bstr = self._makeBaseString( self.mode, address, base_fields )

      // Prepare the Authorization header.
      if self.use_header == UseHeader.ALTERN
         // In use header mode, send OAuth parameters via header.
         query_string = self._makeGet( params )
         headers =  ["Authorization: OAuth realm=\"" +address+"\","+ self._makeAuthHeader( oauth_params ) ]
      elif self.use_header == UseHeader.FULL
         // In use header mode, send OAuth parameters via header AND via query
         query_string = self._makeGet( all_params )
         headers =  ["Authorization: OAuth realm=\"" +address+"\","+ self._makeAuthHeader( oauth_params ) ]
      else
         // Send oauth fields only via query
         query_string = self._makeGet( all_params )
         headers = []
      end

      if self.mode == Via.POST
         cr = curl.Handle( address )
         cr.postData( query_string )
         headers += ["Content-type: application/x-www-form-urlencoded"]
      else
         cr = curl.Handle( address + (query_string ? ("?" + query_string) : "" ))
      end

      if headers: cr.setOption( curl.OPT.HTTPHEADER, headers )
      cr.setOption( curl.OPT.SSL_VERIFYPEER, false )
      return cr
   end

   //==========================================================
   // Generic utilities
   //==========================================================

   function _makeBaseParams()
      params = [
         "client_id" => self.cust_id ,
         "client_secret" => self.secret
      ]

      return params
   end

end