export a handle style decorator
trim21 opened this issue · comments
I'm using handle (async def handle(request) -> Response) in my aiohttp application.
it looks like currently it only support class based view, not request.
I try a code snippet to make it work:
(most of code are copied from inner)
from asyncio import iscoroutinefunction
from functools import update_wrapper
from typing import Callable, Iterable
from aiohttp import web
from aiohttp.web_response import json_response, StreamResponse
from aiohttp_pydantic.injectors import (
CONTEXT, AbstractInjector, _parse_func_signature, MatchInfoGetter, BodyGetter, QueryGetter, HeadersGetter,
)
from pydantic import ValidationError
async def on_validation_error(exception: ValidationError, context: CONTEXT) -> StreamResponse:
"""
This method is a hook to intercept ValidationError.
This hook can be redefined to return a custom HTTP response error.
The exception is a pydantic.ValidationError and the context is "body",
"headers", "path" or "query string"
"""
errors = exception.errors()
for error in errors:
error["in"] = context
return json_response(data=errors, status=400)
def parse_func_signature(func: Callable) -> Iterable[AbstractInjector]:
path_args, body_args, qs_args, header_args, defaults = _parse_func_signature(func)
injectors = []
def default_value(args: dict) -> dict:
"""
Returns the default values of args.
"""
return {name: defaults[name] for name in args if name in defaults}
if path_args:
injectors.append(MatchInfoGetter(path_args, default_value(path_args)))
if body_args:
injectors.append(BodyGetter(body_args, default_value(body_args)))
if qs_args:
injectors.append(QueryGetter(qs_args, default_value(qs_args)))
if header_args:
injectors.append(HeadersGetter(header_args, default_value(header_args)))
return injectors
def decorator(handler):
"""
Decorator to unpack the query string, route path, body and http header in
the parameters of the web handler regarding annotations.
"""
injectors = parse_func_signature(handler)
async def wrapped_handler(request):
args = []
kwargs = {}
for injector in injectors:
try:
if iscoroutinefunction(injector.inject):
await injector.inject(request, args, kwargs)
else:
injector.inject(request, args, kwargs)
except ValidationError as error:
return await on_validation_error(error, injector.context)
return await handler(*args, **kwargs)
update_wrapper(wrapped_handler, handler)
return wrapped_handler
@decorator
async def get(id: int = None, /, with_comments: bool = False, *, user_agent: str = None):
return web.json_response(
{
'id': id,
'UA': user_agent,
'with_comments': with_comments,
}
)
app = web.Application()
app.router.add_get('/{id}', get)
if __name__ == '__main__':
web.run_app(app, port=9092)there is another sugestion:
all *Getter.inject can be asynchronous function, and just call await injector.inject(request, args, kwargs) without iscoroutinefunction call. ( and put BodyGetter at last )
Good job! Have a decorator for HTTP handler function is a great feature but the handler decorator should works with aiohttp_pydantic.oas.view.generate_oas(). and the decorator should take the on_validation_error hook in optional parameter.
Do you want to try to create a Pull requests ?
Sorry to say that, but I'm lazy to create a PR for this...
And I don't use this OAS feature.
No problem, I try to do that the next week. Thanks for your message it's always good to know how people use aiohttp-pydantic or what's it need.
