from djangorestframework.response import status, ResponseException try: import json except ImportError: import simplejson as json # TODO: Make all parsers only list a single media_type, rather than a list class BaseParser(object): """All parsers should extend BaseParser, specifing a media_type attribute, and overriding the parse() method.""" media_type = None def __init__(self, resource): """Initialise the parser with the Resource instance as state, in case the parser needs to access any metadata on the Resource object.""" self.resource = resource def parse(self, input): """Given some serialized input, return the deserialized output. The input will be the raw request content body. The return value may be of any type, but for many parsers/inputs it might typically be a dict.""" return input class JSONParser(BaseParser): media_type = 'application/json' def parse(self, input): try: return json.loads(input) except ValueError, exc: raise ResponseException(status.HTTP_400_BAD_REQUEST, {'detail': 'JSON parse error - %s' % str(exc)}) class XMLParser(BaseParser): media_type = 'application/xml' class FormParser(BaseParser): """The default parser for form data. Return a dict containing a single value for each non-reserved parameter. """ media_type = 'application/x-www-form-urlencoded' def parse(self, input): # The FormParser doesn't parse the input as other parsers would, since Django's already done the # form parsing for us. We build the content object from the request directly. request = self.resource.request if request.method == 'PUT': # Fix from piston to force Django to give PUT requests the same # form processing that POST requests get... # # Bug fix: if _load_post_and_files has already been called, for # example by middleware accessing request.POST, the below code to # pretend the request is a POST instead of a PUT will be too late # to make a difference. Also calling _load_post_and_files will result # in the following exception: # AttributeError: You cannot set the upload handlers after the upload has been processed. # The fix is to check for the presence of the _post field which is set # the first time _load_post_and_files is called (both by wsgi.py and # modpython.py). If it's set, the request has to be 'reset' to redo # the query value parsing in POST mode. if hasattr(request, '_post'): del request._post del request._files try: request.method = "POST" request._load_post_and_files() request.method = "PUT" except AttributeError: request.META['REQUEST_METHOD'] = 'POST' request._load_post_and_files() request.META['REQUEST_METHOD'] = 'PUT' # Strip any parameters that we are treating as reserved data = {} for (key, val) in request.POST.items(): if key not in self.resource.RESERVED_FORM_PARAMS: data[key] = val return data