Source code for webargs.aiohttpparser

"""aiohttp request argument parsing module.

Example: ::

    import asyncio
    from aiohttp import web

    from webargs import fields
    from webargs.aiohttpparser import use_args


    hello_args = {
        'name': fields.Str(required=True)
    }
    @asyncio.coroutine
    @use_args(hello_args)
    def index(request, args):
        return web.Response(
            body='Hello {}'.format(args['name']).encode('utf-8')
        )

    app = web.Application()
    app.router.add_route('GET', '/', index)
"""
import typing

from aiohttp import web
from aiohttp import web_exceptions
from marshmallow import Schema, ValidationError, RAISE

from webargs import core
from webargs.core import json
from webargs.asyncparser import AsyncParser
from webargs.multidictproxy import MultiDictProxy


def is_json_request(req) -> bool:
    content_type = req.content_type
    return core.is_json(content_type)


[docs]class HTTPUnprocessableEntity(web.HTTPClientError): status_code = 422
# Mapping of status codes to exception classes # Adapted from werkzeug exception_map = {422: HTTPUnprocessableEntity} def _find_exceptions() -> None: for name in web_exceptions.__all__: obj = getattr(web_exceptions, name) try: is_http_exception = issubclass(obj, web_exceptions.HTTPException) except TypeError: is_http_exception = False if not is_http_exception or obj.status_code is None: continue old_obj = exception_map.get(obj.status_code, None) if old_obj is not None and issubclass(obj, old_obj): continue exception_map[obj.status_code] = obj # Collect all exceptions from aiohttp.web_exceptions _find_exceptions() del _find_exceptions
[docs]class AIOHTTPParser(AsyncParser): """aiohttp request argument parser.""" DEFAULT_UNKNOWN_BY_LOCATION = { "match_info": RAISE, "path": RAISE, **core.Parser.DEFAULT_UNKNOWN_BY_LOCATION, } __location_map__ = dict( match_info="load_match_info", path="load_match_info", **core.Parser.__location_map__, )
[docs] def load_querystring(self, req, schema: Schema) -> MultiDictProxy: """Return query params from the request as a MultiDictProxy.""" return MultiDictProxy(req.query, schema)
[docs] async def load_form(self, req, schema: Schema) -> MultiDictProxy: """Return form values from the request as a MultiDictProxy.""" post_data = await req.post() return MultiDictProxy(post_data, schema)
[docs] async def load_json_or_form( self, req, schema: Schema ) -> typing.Union[typing.Dict, MultiDictProxy]: data = await self.load_json(req, schema) if data is not core.missing: return data return await self.load_form(req, schema)
[docs] async def load_json(self, req, schema: Schema): """Return a parsed json payload from the request.""" if not (req.body_exists and is_json_request(req)): return core.missing try: return await req.json(loads=json.loads) except json.JSONDecodeError as exc: if exc.doc == "": return core.missing return self._handle_invalid_json_error(exc, req) except UnicodeDecodeError as exc: return self._handle_invalid_json_error(exc, req)
[docs] def load_headers(self, req, schema: Schema) -> MultiDictProxy: """Return headers from the request as a MultiDictProxy.""" return MultiDictProxy(req.headers, schema)
[docs] def load_cookies(self, req, schema: Schema) -> MultiDictProxy: """Return cookies from the request as a MultiDictProxy.""" return MultiDictProxy(req.cookies, schema)
[docs] def load_files(self, req, schema: Schema) -> typing.NoReturn: raise NotImplementedError( "load_files is not implemented. You may be able to use load_form for " "parsing upload data." )
[docs] def load_match_info(self, req, schema: Schema) -> typing.Mapping: """Load the request's ``match_info``.""" return req.match_info
[docs] def get_request_from_view_args( self, view: typing.Callable, args: typing.Iterable, kwargs: typing.Mapping ): """Get request object from a handler function or method. Used internally by ``use_args`` and ``use_kwargs``. """ req = None for arg in args: if isinstance(arg, web.Request): req = arg break if isinstance(arg, web.View): req = arg.request break if not isinstance(req, web.Request): raise ValueError("Request argument not found for handler") return req
[docs] def handle_error( self, error: ValidationError, req, schema: Schema, *, error_status_code: typing.Optional[int], error_headers: typing.Optional[typing.Mapping[str, str]] ) -> typing.NoReturn: """Handle ValidationErrors and return a JSON response of error messages to the client. """ error_class = exception_map.get( error_status_code or self.DEFAULT_VALIDATION_STATUS ) if not error_class: raise LookupError(f"No exception for {error_status_code}") headers = error_headers raise error_class( body=json.dumps(error.messages).encode("utf-8"), headers=headers, content_type="application/json", )
def _handle_invalid_json_error( self, error: typing.Union[json.JSONDecodeError, UnicodeDecodeError], req, *args, **kwargs ) -> typing.NoReturn: error_class = exception_map[400] messages = {"json": ["Invalid JSON body."]} raise error_class( body=json.dumps(messages).encode("utf-8"), content_type="application/json" )
parser = AIOHTTPParser() use_args = parser.use_args # type: typing.Callable use_kwargs = parser.use_kwargs # type: typing.Callable