Abstract Base Classes

Abstract routing

aiohttp has abstract classes for managing web interfaces.

The most part of aiohttp.web is not intended to be inherited but few of them are.

aiohttp.web is built on top of few concepts: application, router, request and response.

router is a pluggable part: a library user may build a router from scratch, all other parts should work with new router seamlessly.

aiohttp.abc.AbstractRouter has the only mandatory method: aiohttp.abc.AbstractRouter.resolve() coroutine. It must return an aiohttp.abc.AbstractMatchInfo instance.

If the requested URL handler is found aiohttp.abc.AbstractMatchInfo.handler() is a web-handler for requested URL and aiohttp.abc.AbstractMatchInfo.http_exception is None.

Otherwise aiohttp.abc.AbstractMatchInfo.http_exception is an instance of HTTPException like 404: NotFound or 405: Method Not Allowed. aiohttp.abc.AbstractMatchInfo.handler() raises http_exception on call.

class aiohttp.abc.AbstractRouter

Abstract router, aiohttp.web.Application accepts it as router parameter and returns as aiohttp.web.Application.router.

async resolve(request)

Performs URL resolving. It’s an abstract method, should be overridden in router implementation.

Parameters:

request – aiohttp.web.Request instance for resolving, the request has aiohttp.web.Request.match_info equals to None at resolving stage.

Returns:

aiohttp.abc.AbstractMatchInfo instance.

class aiohttp.abc.AbstractMatchInfo

Abstract match info, returned by aiohttp.abc.AbstractRouter.resolve() call.

http_exception

aiohttp.web.HTTPException if no match was found, None otherwise.

async handler(request)

Abstract method performing web-handler processing.

Parameters:

request – aiohttp.web.Request instance for resolving, the request has aiohttp.web.Request.match_info equals to None at resolving stage.

Returns:

aiohttp.web.StreamResponse or descendants.

Raise:

aiohttp.web.HTTPException on error

async expect_handler(request)

Abstract method for handling 100-continue processing.

Abstract Class Based Views

For class based view support aiohttp has abstract AbstractView class which is awaitable (may be uses like await Cls() or yield from Cls() and has a request as an attribute.

class aiohttp.abc.AbstractView

An abstract class, base for all class based views implementations.

Methods __iter__ and __await__ should be overridden.

request

aiohttp.web.Request instance for performing the request.

Abstract Cookie Jar

class aiohttp.abc.AbstractCookieJar

The cookie jar instance is available as aiohttp.ClientSession.cookie_jar.

The jar contains Morsel items for storing internal cookie data.

API provides a count of saved cookies:

len(session.cookie_jar)

These cookies may be iterated over:

for cookie in session.cookie_jar:
    print(cookie.key)
    print(cookie["domain"])

An abstract class for cookie storage. Implements collections.abc.Iterable and collections.abc.Sized.

update_cookies(cookies, response_url=None)

Update cookies returned by server in Set-Cookie header.

Parameters:

• cookies – a collections.abc.Mapping (e.g. dict, SimpleCookie) or iterable of pairs with cookies returned by server’s response.

• response_url (str) – URL of response, None for shared cookies. Regular cookies are coupled with server’s URL and are sent only to this server, shared ones are sent in every client request.

filter_cookies(request_url)

Return jar’s cookies acceptable for URL and available in Cookie header for sending client requests for given URL.

Parameters:

response_url (str) – request’s URL for which cookies are asked.

Returns:

http.cookies.SimpleCookie with filtered cookies for given URL.

clear(predicate=None)

Removes all cookies from the jar if the predicate is None. Otherwise remove only those Morsel that predicate(morsel) returns True.

Parameters:

predicate –

callable that gets Morsel as a parameter and returns True if this Morsel must be deleted from the jar.

New in version 3.8.

clear_domain(domain)

Remove all cookies from the jar that belongs to the specified domain or its subdomains.

Parameters:

domain (str) – domain for which cookies must be deleted from the jar.

New in version 3.8.

Abstract Access Logger

class aiohttp.abc.AbstractAccessLogger

An abstract class, base for all aiohttp.web.RequestHandler access_logger implementations

Method log should be overridden.

log(request, response, time)

Parameters:

• request – aiohttp.web.Request object.

• response – aiohttp.web.Response object.

• time (float) – Time taken to serve the request.