parameters: (http_method, http_url, headers=None, parameters=None,
              query_string=None)
return_statement: return None
docstring: Combines multiple parameter sources.
docstring_summary: Combines multiple parameter sources.
docstring_tokens: Combines multiple parameter sources .
function: def from_request(http_method, http_url, headers=None, parameters=None,
              query_string=None):
          """Combines multiple parameter sources."""
          if parameters is None:
              parameters = {}
  
          # Headers
          if headers and 'Authorization' in headers:
              auth_header = headers['Authorization']
              # Check that the authorization header is OAuth.
              if auth_header[:6] == 'OAuth ':
                  auth_header = auth_header[6:]
                  try:
                      # Get the parameters from the header.
                      header_params = OAuthRequest._split_header(auth_header)
                      parameters.update(header_params)
                  except:
                      raise OAuthError('Unable to parse OAuth parameters from '
                          'Authorization header.')
  
          # GET or POST query string.
          if query_string:
              query_params = OAuthRequest._split_url_string(query_string)
              parameters.update(query_params)
  
          # URL parameters.
          param_str = urllib.parse.urlparse(http_url)[4] # query
          url_params = OAuthRequest._split_url_string(param_str)
          parameters.update(url_params)
  
          if parameters:
              return OAuthRequest(http_method, http_url, parameters)
  
          return None
function_tokens: def from_request ( http_method , http_url , headers = None , parameters = None , query_string = None ) : if parameters is None : parameters = { } # Headers if headers and 'Authorization' in headers : auth_header = headers [ 'Authorization' ] # Check that the authorization header is OAuth. if auth_header [ : 6 ] == 'OAuth ' : auth_header = auth_header [ 6 : ] try : # Get the parameters from the header. header_params = OAuthRequest . _split_header ( auth_header ) parameters . update ( header_params ) except : raise OAuthError ( 'Unable to parse OAuth parameters from ' 'Authorization header.' ) # GET or POST query string. if query_string : query_params = OAuthRequest . _split_url_string ( query_string ) parameters . update ( query_params ) # URL parameters. param_str = urllib . parse . urlparse ( http_url ) [ 4 ] # query url_params = OAuthRequest . _split_url_string ( param_str ) parameters . update ( url_params ) if parameters : return OAuthRequest ( http_method , http_url , parameters ) return None