Usage

Quickstart

Note

Using strict=True need only for marshmallow < 3.0.0

from aiohttp_apispec import (docs,
                             request_schema,
                             response_schema,
                             setup_aiohttp_apispec)
from aiohttp import web
from marshmallow import Schema, fields


class RequestSchema(Schema):
    id = fields.Int()
    name = fields.Str(description='name')
    bool_field = fields.Bool()


class ResponseSchema(Schema):
    msg = fields.Str()
    data = fields.Dict()


@docs(tags=['mytag'],
      summary='Test method summary',
      description='Test method description')
@request_schema(RequestSchema(strict=True))
@response_schema(ResponseSchema(), 200)
async def index(request):
    return web.json_response({'msg': 'done',
                              'data': {}})

# Class based views are also supported:
class TheView(web.View):
    @docs(
        tags=['mytag'],
        summary='View method summary',
        description='View method description',
    )
    @request_schema(RequestSchema(strict=True))
    def delete(self):
        return web.json_response({
            'msg': 'done',
            'data': {'name': self.request['data']['name']},
        })


app = web.Application()
app.router.add_post('/v1/test', index)
app.router.add_view('/v1/view', TheView)

# init docs with all parameters, usual for ApiSpec
setup_aiohttp_apispec(app=app, title="My Documentation", version="v1")


# find it on 'http://localhost:8080/api/docs/api-docs'
web.run_app(app)

Adding validation middleware

from aiohttp_apispec import validation_middleware

...

app.middlewares.append(validation_middleware)

Now you can access all validated data in route from request['data'] like so:

@docs(tags=['mytag'],
      summary='Test method summary',
      description='Test method description')
@request_schema(RequestSchema(strict=True))
@response_schema(ResponseSchema(), 200)
async def index(request):
    uid = request['data']['id']
    name = request['data']['name']
    return web.json_response(
        {'msg': 'done',
         'data': {'info': f'name - {name}, id - {uid}'}}
     )

You can change Request’s 'data' param to another with request_data_name argument of setup_aiohttp_apispec function:

setup_aiohttp_apispec(app=app,
                      request_data_name='validated_data',
                      title='My Documentation',
                      version='v1',
                      url='/api/docs/api-docs')

...

@request_schema(RequestSchema(strict=True))
async def index(request):
    uid = request['validated_data']['id']
    ...

More decorators

Starting from version 2.0 you can use shortenings for documenting and validating specific request parts like cookies, headers etc using those decorators:

Decorator name Default put_into param
match_info_schema match_info
querystring_schema querystring
form_schema form
json_schema json
headers_schema headers
cookies_schema cookies

And example:

@docs(
    tags=["users"],
    summary="Create new user",
    description="Add new user to our toy database",
    responses={
        200: {"description": "Ok. User created", "schema": OkResponse},
        401: {"description": "Unauthorized"},
        422: {"description": "Validation error"},
        500: {"description": "Server error"},
    },
)
@headers_schema(AuthHeaders)
@json_schema(UserMeta)
@querystring_schema(UserParams)
async def create_user(request: web.Request):
    headers = request["headers"]  # <- validated headers!
    json_data = request["json"]  # <- validated json!
    query_params = request["querystring"]  # <- validated querystring!
    ...

Custom error handling

If you want to catch validation errors by yourself you could use error_callback parameter and create your custom error handler. Note that it can be one of coroutine or callable and it should have interface exactly like in examples below:

from marshmallow import ValidationError, Schema
from aiohttp import web
from typing import Optional, Mapping, NoReturn


def my_error_handler(
    error: ValidationError,
    req: web.Request,
    schema: Schema,
    error_status_code: Optional[int] = None,
    error_headers: Optional[Mapping[str, str]] = None,
) -> NoReturn:
    raise web.HTTPBadRequest(
            body=json.dumps(error.messages),
            headers=error_headers,
            content_type="application/json",
        )

setup_aiohttp_apispec(app, error_callback=my_error_handler)

Also you can create your own exceptions and create regular Request in middleware like so:

class MyException(Exception):
    def __init__(self, message):
        self.message = message

# It can be coroutine as well:
async def my_error_handler(
    error: ValidationError,
    req: web.Request,
    schema: Schema,
    error_status_code: Optional[int] = None,
    error_headers: Optional[Mapping[str, str]] = None,
) -> NoReturn:
    await req.app["db"].do_smth()  # So you can use some async stuff
    raise MyException({"errors": error.messages, "text": "Oops"})

# This middleware will handle your own exceptions:
@web.middleware
async def intercept_error(request, handler):
    try:
        return await handler(request)
    except MyException as e:
        return web.json_response(e.message, status=400)


setup_aiohttp_apispec(app, error_callback=my_error_handler)

# Do not forget to add your own middleware before validation_middleware
app.middlewares.extend([intercept_error, validation_middleware])

Named routes

Routes for the Swagger UI and to the swagger specification file swagger.json are registered as `named resources <https://docs.aiohttp.org/en/stable/web_quickstart.html#reverse-url-constructing-using-named-resources`_ with the swagger.docs and swagger.spec names respectively. The corresponding routes are therefore avaialble un the value returned by the application’s router named_resources() call.

Build swagger web client

3.X SwaggerUI version

Just add swagger_path parameter to setup_aiohttp_apispec function.

For example:

Then go to /docs and see awesome SwaggerUI

2.X SwaggerUI version

aiohttp-apispec adds swagger_dict parameter to aiohttp web application after initialization (with setup_aiohttp_apispec function). So you can use it easily with aiohttp_swagger library:

from aiohttp_apispec import setup_aiohttp_apispec
from aiohttp_swagger import setup_swagger


def create_app(app):
    setup_aiohttp_apispec(app)

    async def swagger(app):
        setup_swagger(
            app=app, swagger_url='/api/doc', swagger_info=app['swagger_dict']
        )
    app.on_startup.append(swagger)
    # now we can access swagger client on '/api/doc' url
    ...
    return app

Now we can access swagger client on /api/doc url