parse path and header

This commit is contained in:
Vincent Maillol 2020-10-09 22:03:37 +02:00
parent cc0cbfbb5e
commit b37c03e9d9
7 changed files with 283 additions and 102 deletions

View File

@ -1,102 +1,3 @@
from aiohttp.abc import AbstractView
from aiohttp.hdrs import METH_ALL
from aiohttp.web_exceptions import HTTPMethodNotAllowed
from aiohttp.web_response import StreamResponse
from pydantic import BaseModel, ValidationError
from typing import Generator, Any
from aiohttp.web import json_response
from .view import PydanticView
class PydanticView(AbstractView):
async def _iter(self) -> StreamResponse:
method = getattr(self, self.request.method.lower(), None)
resp = await method()
return resp
def __await__(self) -> Generator[Any, None, StreamResponse]:
return self._iter().__await__()
def __init_subclass__(cls, **kwargs):
allowed_methods = {
meth_name for meth_name in METH_ALL
if hasattr(cls, meth_name.lower())}
async def raise_not_allowed(self):
raise HTTPMethodNotAllowed(self.request.method, allowed_methods)
if 'GET' in allowed_methods:
cls.get = inject_qs(cls.get)
if 'POST' in allowed_methods:
cls.post = inject_body(cls.post)
if 'PUT' in allowed_methods:
cls.put = inject_body(cls.put)
for meth_name in METH_ALL:
if meth_name not in allowed_methods:
setattr(cls, meth_name.lower(), raise_not_allowed)
def inject_qs(handler):
"""
Decorator to unpack the query string in the parameters of the web handler
regarding annotations.
"""
nb_header_params = handler.__code__.co_kwonlyargcount
if nb_header_params:
from_qs = frozenset(handler.__code__.co_varnames[:-nb_header_params])
from_header = frozenset(handler.__code__.co_varnames[-nb_header_params:])
else:
from_qs = frozenset(handler.__code__.co_varnames)
from_header = frozenset()
qs_model_class = type(
'QSModel', (BaseModel,),
{'__annotations__': {k: v for k, v in handler.__annotations__.items() if k in from_qs and k != 'self'}})
header_model_class = type(
'HeaderModel', (BaseModel,),
{'__annotations__': {k: v for k, v in handler.__annotations__.items() if k in from_header and k != 'self'}})
async def wrapped_handler(self):
try:
qs = qs_model_class(**self.request.query)
header = header_model_class(**self.request.headers)
except ValidationError as error:
return json_response(text=error.json(), status=400)
# raise HTTPBadRequest(
# reason='\n'.join(
# f'Error with query string parameter {", ".join(err["loc"])}:'
# f' {err["msg"]}' for err in error.errors()))
return await handler(self, **qs.dict(), **header.dict())
return wrapped_handler
def inject_body(handler):
"""
Decorator to inject the request body as parameter of the web handler
regarding annotations.
"""
arg_name, model_class = next(
((arg_name, arg_type)
for arg_name, arg_type in handler.__annotations__.items()
if issubclass(arg_type, BaseModel)), (None, None))
if arg_name is None:
return handler
async def wrapped_handler(self):
body = await self.request.json()
try:
model = model_class(**body)
except ValidationError as error:
return json_response(text=error.json(), status=400)
return await handler(self, **{arg_name: model})
return wrapped_handler
__all__ = ("PydanticView",)

View File

@ -0,0 +1,109 @@
from typing import Callable, Tuple
from aiohttp.web_request import BaseRequest
from pydantic import BaseModel
from inspect import signature
import abc
class AbstractInjector(metaclass=abc.ABCMeta):
"""
An injector parse HTTP request and inject params to the view.
"""
@abc.abstractmethod
def __init__(self, args_spec: dict):
"""
args_spec - ordered mapping: arg_name -> type
"""
@abc.abstractmethod
def inject(self, request: BaseRequest, args_view: list, kwargs_view: dict):
"""
Get elements in request and inject them in args_view or kwargs_view.
"""
class MatchInfoGetter(AbstractInjector):
"""
Validates and injects the part of URL path inside the view positional args.
"""
def __init__(self, args_spec: dict):
self.model = type("PathModel", (BaseModel,), {"__annotations__": args_spec})
def inject(self, request: BaseRequest, args_view: list, kwargs_view: dict):
args_view.extend(self.model(**request.match_info).dict().values())
class BodyGetter(AbstractInjector):
"""
Validates and injects the content of request body inside the view kwargs.
"""
def __init__(self, args_spec: dict):
self.arg_name, self.model = next(iter(args_spec.items()))
async def inject(self, request: BaseRequest, args_view: list, kwargs_view: dict):
body = await request.json()
kwargs_view[self.arg_name] = self.model(**body)
class QueryGetter(AbstractInjector):
"""
Validates and injects the query string inside the view kwargs.
"""
def __init__(self, args_spec: dict):
self.model = type("QueryModel", (BaseModel,), {"__annotations__": args_spec})
def inject(self, request: BaseRequest, args_view: list, kwargs_view: dict):
kwargs_view.update(self.model(**request.query).dict())
class HeadersGetter(AbstractInjector):
"""
Validates and injects the HTTP headers inside the view kwargs.
"""
def __init__(self, args_spec: dict):
self.model = type("HeaderModel", (BaseModel,), {"__annotations__": args_spec})
def inject(self, request: BaseRequest, args_view: list, kwargs_view: dict):
header = {k.lower().replace("-", "_"): v for k, v in request.headers.items()}
kwargs_view.update(self.model(**header).dict())
def _parse_func_signature(func: Callable) -> Tuple[dict, dict, dict, dict]:
"""
Analyse function signature and returns 4-tuple:
0 - arguments will be set from the url path
1 - argument will be set from the request body.
2 - argument will be set from the query string.
3 - argument will be set from the HTTP headers.
"""
path_args = {}
body_args = {}
qs_args = {}
header_args = {}
for param_name, param_spec in signature(func).parameters.items():
if param_name == "self":
continue
if param_spec.kind is param_spec.POSITIONAL_ONLY:
path_args[param_name] = param_spec.annotation
elif param_spec.kind is param_spec.POSITIONAL_OR_KEYWORD:
if issubclass(param_spec.annotation, BaseModel):
body_args[param_name] = param_spec.annotation
else:
qs_args[param_name] = param_spec.annotation
elif param_spec.kind is param_spec.KEYWORD_ONLY:
header_args[param_name] = param_spec.annotation
else:
raise RuntimeError(f"You cannot use {param_spec.VAR_POSITIONAL} parameters")
return path_args, body_args, qs_args, header_args

92
aiohttp_pydantic/view.py Normal file
View File

@ -0,0 +1,92 @@
from inspect import iscoroutinefunction
from aiohttp.abc import AbstractView
from aiohttp.hdrs import METH_ALL
from aiohttp.web_exceptions import HTTPMethodNotAllowed
from aiohttp.web_response import StreamResponse
from pydantic import ValidationError
from typing import Generator, Any, Callable, List, Iterable
from aiohttp.web import json_response
from functools import update_wrapper
from .injectors import (
MatchInfoGetter,
HeadersGetter,
QueryGetter,
BodyGetter,
AbstractInjector,
_parse_func_signature,
)
class PydanticView(AbstractView):
"""
An AIOHTTP View that validate request using function annotations.
"""
async def _iter(self) -> StreamResponse:
method = getattr(self, self.request.method.lower(), None)
resp = await method()
return resp
def __await__(self) -> Generator[Any, None, StreamResponse]:
return self._iter().__await__()
def __init_subclass__(cls, **kwargs):
allowed_methods = {
meth_name for meth_name in METH_ALL if hasattr(cls, meth_name.lower())
}
async def raise_not_allowed(self):
raise HTTPMethodNotAllowed(self.request.method, allowed_methods)
for meth_name in METH_ALL:
if meth_name not in allowed_methods:
setattr(cls, meth_name.lower(), raise_not_allowed)
else:
handler = getattr(cls, meth_name.lower())
decorated_handler = inject_params(handler, cls.parse_func_signature)
setattr(cls, meth_name.lower(), decorated_handler)
@staticmethod
def parse_func_signature(func: Callable) -> Iterable[AbstractInjector]:
path_args, body_args, qs_args, header_args = _parse_func_signature(func)
injectors = []
if path_args:
injectors.append(MatchInfoGetter(path_args))
if body_args:
injectors.append(BodyGetter(body_args))
if qs_args:
injectors.append(QueryGetter(qs_args))
if header_args:
injectors.append(HeadersGetter(header_args))
return injectors
def inject_params(
handler, parse_func_signature: Callable[[Callable], Iterable[AbstractInjector]]
):
"""
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(self):
args = []
kwargs = {}
for injector in injectors:
try:
if iscoroutinefunction(injector.inject):
await injector.inject(self.request, args, kwargs)
else:
injector.inject(self.request, args, kwargs)
except ValidationError as error:
return json_response(text=error.json(), status=400)
return await handler(self, *args, **kwargs)
update_wrapper(wrapped_handler, handler)
return wrapped_handler

View File

@ -17,7 +17,6 @@ setup(
'Programming Language :: Python',
'Programming Language :: Python :: 3',
'Programming Language :: Python :: 3 :: Only',
'Programming Language :: Python :: 3.6',
'Programming Language :: Python :: 3.7',
'Programming Language :: Python :: 3.8',
'Programming Language :: Python :: 3.9',

View File

@ -0,0 +1,49 @@
from aiohttp_pydantic.injectors import _parse_func_signature
from pydantic import BaseModel
from uuid import UUID
class User(BaseModel):
firstname: str
lastname: str
def test_parse_func_signature():
def body_only(self, user: User):
pass
def path_only(self, id: str, /):
pass
def qs_only(self, page: int):
pass
def header_only(self, *, auth: UUID):
pass
def path_and_qs(self, id: str, /, page: int):
pass
def path_and_header(self, id: str, /, *, auth: UUID):
pass
def qs_and_header(self, page: int, *, auth: UUID):
pass
def path_qs_and_header(self, id: str, /, page: int, *, auth: UUID):
pass
def path_body_qs_and_header(self, id: str, /, user: User, page: int, *, auth: UUID):
pass
assert _parse_func_signature(body_only) == ({}, {'user': User}, {}, {})
assert _parse_func_signature(path_only) == ({'id': str}, {}, {}, {})
assert _parse_func_signature(qs_only) == ({}, {}, {'page': int}, {})
assert _parse_func_signature(header_only) == ({}, {}, {}, {'auth': UUID})
assert _parse_func_signature(path_and_qs) == ({'id': str}, {}, {'page': int}, {})
assert _parse_func_signature(path_and_header) == ({'id': str}, {}, {}, {'auth': UUID})
assert _parse_func_signature(qs_and_header) == ({}, {}, {'page': int}, {'auth': UUID})
assert _parse_func_signature(path_qs_and_header) == ({'id': str}, {}, {'page': int}, {'auth': UUID})
assert _parse_func_signature(path_body_qs_and_header) == ({'id': str}, {'user': User}, {'page': int}, {'auth': UUID})

View File

@ -54,3 +54,14 @@ async def test_get_article_with_valid_header_should_return_the_parsed_type(aioht
assert resp.status == 200
assert resp.content_type == 'application/json'
assert await resp.json() == {'signature': '2020-10-04T18:01:00'}
async def test_get_article_with_valid_header_containing_hyphen_should_be_returned(aiohttp_client, loop):
app = web.Application()
app.router.add_view('/article', ArticleView)
client = await aiohttp_client(app)
resp = await client.get('/article', headers={'Signature-Expired': '2020-10-04T18:01:00'})
assert resp.status == 200
assert resp.content_type == 'application/json'
assert await resp.json() == {'signature': '2020-10-04T18:01:00'}

View File

@ -0,0 +1,20 @@
from aiohttp import web
from aiohttp_pydantic import PydanticView
class ArticleView(PydanticView):
async def get(self, author_id: str, tag: str, date: int, /):
return web.json_response({'path': [author_id, tag, date]})
async def test_get_article_without_required_qs_should_return_an_error_message(aiohttp_client, loop):
app = web.Application()
app.router.add_view('/article/{author_id}/tag/{tag}/before/{date}', ArticleView)
client = await aiohttp_client(app)
resp = await client.get('/article/1234/tag/music/before/1980')
assert resp.status == 200
assert resp.content_type == 'application/json'
assert await resp.json() == {'path': ['1234', 'music', 1980]}