Added aiohttp support

README.rst

@@ -416,6 +416,17 @@ Flask with uWSGI`_ (this is common):
     app = connexion.App(__name__, specification_dir='swagger/')
     application = app.app # expose global WSGI application object
 
+You can use the ``aiohttp`` framework as server backend as well:
+
+.. code-block:: python
+
+    import connexion
+
+    app = connexion.AioHttpApp(__name__, specification_dir='swagger/')
+    app.run(port=8080)
+
+**NOTE:** Also check aiohttp handler examples_.
+
 Set up and run the installation code:
 
 .. code-block:: bash
@@ -427,6 +438,8 @@ See the `uWSGI documentation`_ for more information.
 
 .. _using Flask with uWSGI: http://flask.pocoo.org/docs/latest/deploying/uwsgi/
 .. _uWSGI documentation: https://uwsgi-docs.readthedocs.org/
+.. _examples: https://docs.aiohttp.org/en/stable/web.html#handler
+
 
 Documentation
 =============

connexion/__init__.py

@@ -6,25 +6,39 @@
 from .decorators.produces import NoContent  # NOQA
 from .resolver import Resolution, Resolver, RestyResolver  # NOQA
 
-try:
-    from .apis.flask_api import FlaskApi
-    from .apps.flask_app import FlaskApp
-    from flask import request  # NOQA
-except ImportError as e:  # pragma: no cover
-    import sys
+import sys
+
+
+def not_installed_error():  # pragma: no cover
     import six
     import functools
 
     def _required_lib(exec_info, *args, **kwargs):
         six.reraise(*exec_info)
 
-    _flask_not_installed_error = functools.partial(_required_lib, sys.exc_info())
+    return functools.partial(_required_lib, sys.exc_info())
 
+
+try:
+    from .apis.flask_api import FlaskApi
+    from .apps.flask_app import FlaskApp
+    from flask import request  # NOQA
+except ImportError:  # pragma: no cover
+    _flask_not_installed_error = not_installed_error()
     FlaskApi = _flask_not_installed_error
     FlaskApp = _flask_not_installed_error
 
 App = FlaskApp
 Api = FlaskApi
 
+if sys.version_info[0] >= 3:  # pragma: no cover
+    try:
+        from .apis.aiohttp_api import AioHttpApi
+        from .apps.aiohttp_app import AioHttpApp
+    except ImportError:  # pragma: no cover
+        _aiohttp_not_installed_error = not_installed_error()
+        AioHttpApi = _aiohttp_not_installed_error
+        AioHttpApp = _aiohttp_not_installed_error
+
 # This version is replaced during release process.
 __version__ = '2018.0.dev1'

connexion/apis/abstract.py

@@ -14,6 +14,7 @@
 from ..operation import Operation
 from ..options import ConnexionOptions
 from ..resolver import Resolver
+from ..utils import Jsonifier
 
 MODULE_PATH = pathlib.Path(__file__).absolute().parent.parent
 SWAGGER_UI_PATH = MODULE_PATH / 'vendor' / 'swagger-ui'
@@ -24,7 +25,14 @@
 logger = logging.getLogger('connexion.apis.abstract')
 
 
-@six.add_metaclass(abc.ABCMeta)
+class AbstractAPIMeta(abc.ABCMeta):
+
+    def __init__(cls, name, bases, attrs):
+        abc.ABCMeta.__init__(cls, name, bases, attrs)
+        cls._set_jsonifier()
+
+
+@six.add_metaclass(AbstractAPIMeta)
 class AbstractAPI(object):
     """
     Defines an abstract interface for a Swagger API
@@ -297,14 +305,20 @@ def get_response(self, response, mimetype=None, request=None):
 
     @classmethod
     @abc.abstractmethod
-    def json_loads(self, data):
+    def get_connexion_response(cls, response):
         """
-        API specific JSON loader.
-
-        :param data:
-        :return:
+        This method converts the user framework response to a ConnexionResponse.
+        :param response: A response to cast.
         """
 
+    def json_loads(self, data):
+        return self.jsonifier.loads(data)
+
+    @classmethod
+    def _set_jsonifier(cls):
+        import json
+        cls.jsonifier = Jsonifier(json)
+
 
 def canonical_base_path(base_path):
     """

connexion/apis/aiohttp_api.py

@@ -0,0 +1,266 @@
+import asyncio
+import logging
+import re
+from urllib.parse import parse_qs
+
+import jinja2
+
+import aiohttp_jinja2
+from aiohttp import web
+from aiohttp.web_exceptions import HTTPNotFound
+from connexion.apis.abstract import AbstractAPI
+from connexion.exceptions import OAuthProblem
+from connexion.handlers import AuthErrorHandler
+from connexion.lifecycle import ConnexionRequest, ConnexionResponse
+from connexion.utils import Jsonifier, is_json_mimetype
+
+try:
+    import ujson as json
+    from functools import partial
+    json.dumps = partial(json.dumps, escape_forward_slashes=True)
+
+except ImportError:  # pragma: no cover
+    import json
+
+logger = logging.getLogger('connexion.apis.aiohttp_api')
+
+
+@web.middleware
+@asyncio.coroutine
+def oauth_problem_middleware(request, handler):
+    try:
+        response = yield from handler(request)
+    except OAuthProblem as oauth_error:
+        return web.Response(
+            status=oauth_error.code,
+            body=json.dumps(oauth_error.description).encode(),
+            content_type='application/problem+json'
+        )
+    return response
+
+
+class AioHttpApi(AbstractAPI):
+    def __init__(self, *args, **kwargs):
+        self.subapp = web.Application(
+            debug=kwargs.get('debug', False),
+            middlewares=[oauth_problem_middleware]
+        )
+        AbstractAPI.__init__(self, *args, **kwargs)
+
+        aiohttp_jinja2.setup(
+            self.subapp,
+            loader=jinja2.FileSystemLoader(
+                str(self.options.openapi_console_ui_from_dir)
+            )
+        )
+        middlewares = self.options.as_dict().get('middlewares', [])
+        self.subapp.middlewares.extend(middlewares)
+
+    def _set_base_path(self, base_path):
+        AbstractAPI._set_base_path(self, base_path)
+        self._api_name = AioHttpApi.normalize_string(self.base_path)
+
+    @staticmethod
+    def normalize_string(string):
+        return re.sub(r'[^a-zA-Z0-9]', '_', string.strip('/'))
+
+    def add_swagger_json(self):
+        """
+        Adds swagger json to {base_path}/swagger.json
+        """
+        logger.debug('Adding swagger.json: %s/swagger.json', self.base_path)
+        self.subapp.router.add_route(
+            'GET',
+            '/swagger.json',
+            self._get_swagger_json
+        )
+
+    @asyncio.coroutine
+    def _get_swagger_json(self, req):
+        return web.Response(
+            status=200,
+            content_type='application/json',
+            body=self.jsonifier.dumps(self.specification)
+        )
+
+    def add_swagger_ui(self):
+        """
+        Adds swagger ui to {base_path}/ui/
+        """
+        console_ui_path = self.options.openapi_console_ui_path.strip().rstrip('/')
+        logger.debug('Adding swagger-ui: %s%s/',
+                     self.base_path,
+                     console_ui_path)
+
+        for path in (
+            console_ui_path,
+            console_ui_path + '/',
+            console_ui_path + '/index.html',
+        ):
+            self.subapp.router.add_route(
+                'GET',
+                path,
+                self._get_swagger_ui_home
+            )
+
+        self.subapp.router.add_static(
+            console_ui_path + '/',
+            path=str(self.options.openapi_console_ui_from_dir),
+            name='swagger_ui_static'
+        )
+
+    @aiohttp_jinja2.template('index.html')
+    @asyncio.coroutine
+    def _get_swagger_ui_home(self, req):
+        return {'api_url': self.base_path}
+
+    def add_auth_on_not_found(self, security, security_definitions):
+        """
+        Adds a 404 error handler to authenticate and only expose the 404 status if the security validation pass.
+        """
+        logger.debug('Adding path not found authentication')
+        not_found_error = AuthErrorHandler(
+            self, _HttpNotFoundError(),
+            security=security,
+            security_definitions=security_definitions
+        )
+        endpoint_name = "{}_not_found".format(self._api_name)
+        self.subapp.router.add_route(
+            '*',
+            '/{not_found_path}',
+            not_found_error.function,
+            name=endpoint_name
+        )
+
+    def _add_operation_internal(self, method, path, operation):
+        method = method.upper()
+        operation_id = operation.operation_id or path
+
+        logger.debug('... Adding %s -> %s', method, operation_id,
+                     extra=vars(operation))
+
+        handler = operation.function
+        endpoint_name = '{}_{}_{}'.format(
+            self._api_name,
+            AioHttpApi.normalize_string(path),
+            method.lower()
+        )
+        self.subapp.router.add_route(
+            method, path, handler, name=endpoint_name
+        )
+
+        if not path.endswith('/'):
+            self.subapp.router.add_route(
+                method, path + '/', handler, name=endpoint_name + '_'
+            )
+
+    @classmethod
+    @asyncio.coroutine
+    def get_request(cls, req):
+        """Convert aiohttp request to connexion
+
+        :param req: instance of aiohttp.web.Request
+        :return: connexion request instance
+        :rtype: ConnexionRequest
+        """
+        url = str(req.url)
+        logger.debug('Getting data and status code',
+                     extra={'has_body': req.has_body, 'url': url})
+
+        query = {k: ','.join(v) for k, v in parse_qs(req.rel_url.query_string).items()}
+        headers = {k.decode(): v.decode() for k, v in req.raw_headers}
+        body = None
+        if req.can_read_body:
+            body = yield from req.read()
+
+        return ConnexionRequest(url=url,
+                                method=req.method.lower(),
+                                path_params=dict(req.match_info),
+                                query=query,
+                                headers=headers,
+                                body=body,
+                                json_getter=lambda: cls.jsonifier.loads(body),
+                                files={})
+
+    @classmethod
+    @asyncio.coroutine
+    def get_response(cls, response, mimetype=None, request=None):
+        """Get response.
+        This method is used in the lifecycle decorators
+
+        :rtype: aiohttp.web.Response
+        """
+        while asyncio.iscoroutine(response):
+            response = yield from response
+
+        url = str(request.url) if request else ''
+
+        logger.debug('Getting data and status code',
+                     extra={
+                         'data': response,
+                         'url': url
+                     })
+
+        if isinstance(response, ConnexionResponse):
+            response = cls._get_aiohttp_response_from_connexion(response, mimetype)
+
+        logger.debug('Got data and status code (%d)',
+                     response.status, extra={'data': response.body, 'url': url})
+
+        return response
+
+    @classmethod
+    def get_connexion_response(cls, response):
+        return ConnexionResponse(
+            status_code=response.status,
+            mimetype=response.content_type,
+            content_type=response.content_type,
+            headers=response.headers,
+            body=response.body
+        )
+
+    @classmethod
+    def _get_aiohttp_response_from_connexion(cls, response, mimetype):
+        content_type = response.content_type if response.content_type else \
+            response.mimetype if response.mimetype else mimetype
+
+        body = cls._cast_body(response.body, content_type)
+
+        return web.Response(
+            status=response.status_code,
+            content_type=content_type,
+            headers=response.headers,
+            body=body
+        )
+
+    @classmethod
+    def _cast_body(cls, body, content_type):
+        if not isinstance(body, bytes):
+            if is_json_mimetype(content_type):
+                return json.dumps(body).encode()
+
+            elif isinstance(body, str):
+                return body.encode()
+
+            else:
+                return str(body).encode()
+        else:
+            return body
+
+    @classmethod
+    def _set_jsonifier(cls):
+        cls.jsonifier = Jsonifier(json)
+
+
+class _HttpNotFoundError(HTTPNotFound):
+    def __init__(self):
+        self.name = 'Not Found'
+        self.description = (
+            'The requested URL was not found on the server.  '
+            'If you entered the URL manually please check your spelling and '
+            'try again.'
+        )
+        self.code = type(self).status_code
+        self.empty_body = True
+
+        HTTPNotFound.__init__(self, reason=self.name)