Add type annotations (#285)

Author: asvetlov

.gitignore

@@ -58,4 +58,6 @@ coverage/
 .pytest_cache
 
 # code editors
-.vscode
+.vscode
+
+.mypy_cache

MANIFEST.in

@@ -2,6 +2,9 @@ include CHANGES.txt
 include LICENSE
 include README.rst
 include Makefile
+include requirements-dev.txt
+include pytest.ini
+include .coveragerc
 graft aiohttp_jinja2
 graft docs
 graft examples

Makefile

@@ -2,6 +2,7 @@
 
 flake:
 	flake8 aiohttp_jinja2 tests 
+	mypy --strict aiohttp_jinja2
 
 test: flake
 	py.test -s ./tests/

aiohttp_jinja2/__init__.py

@@ -2,7 +2,8 @@
 import functools
 import warnings
 import jinja2
-from collections import Mapping
+from collections.abc import Mapping
+from typing import Any, Awaitable, Callable, Dict, Iterable, Optional, cast
 from aiohttp import web
 from aiohttp.abc import AbstractView
 from .helpers import GLOBAL_HELPERS
@@ -18,10 +19,17 @@
 REQUEST_CONTEXT_KEY = 'aiohttp_jinja2_context'
 
 
-def setup(app, *args, app_key=APP_KEY, context_processors=(),
-          filters=None, default_helpers=True, autoescape=True,
-          **kwargs):
-    env = jinja2.Environment(*args, autoescape=autoescape, **kwargs)
+def setup(
+    app: web.Application,
+    *args: Any,
+    app_key: str = APP_KEY,
+    context_processors: Iterable[Callable[[web.Request], Dict[str, Any]]] = (),
+    filters: Optional[Iterable[Callable[..., str]]] = None,
+    default_helpers: bool = True,
+    **kwargs: Any
+) -> jinja2.Environment:
+    kwargs.setdefault("autoescape", True)
+    env = jinja2.Environment(*args, **kwargs)
     if default_helpers:
         env.globals.update(GLOBAL_HELPERS)
     if filters is not None:
@@ -36,11 +44,21 @@ def setup(app, *args, app_key=APP_KEY, context_processors=(),
     return env
 
 
-def get_env(app, *, app_key=APP_KEY):
-    return app.get(app_key)
+def get_env(
+    app: web.Application,
+    *,
+    app_key: str = APP_KEY
+) -> jinja2.Environment:
+    return cast(jinja2.Environment, app.get(app_key))
 
 
-def render_string(template_name, request, context, *, app_key=APP_KEY):
+def render_string(
+    template_name: str,
+    request: web.Request,
+    context: Dict[str, Any],
+    *,
+    app_key: str = APP_KEY
+) -> str:
     env = request.config_dict.get(app_key)
     if env is None:
         text = ("Template engine is not initialized, "
@@ -65,8 +83,15 @@ def render_string(template_name, request, context, *, app_key=APP_KEY):
     return text
 
 
-def render_template(template_name, request, context, *,
-                    app_key=APP_KEY, encoding='utf-8', status=200):
+def render_template(
+    template_name: str,
+    request: web.Request,
+    context: Dict[str, Any],
+    *,
+    app_key: str = APP_KEY,
+    encoding: str = 'utf-8',
+    status: int = 200
+) -> web.Response:
     response = web.Response(status=status)
     if context is None:
         context = {}
@@ -77,11 +102,17 @@ def render_template(template_name, request, context, *,
     return response
 
 
-def template(template_name, *, app_key=APP_KEY, encoding='utf-8', status=200):
+def template(
+    template_name: str,
+    *,
+    app_key: str = APP_KEY,
+    encoding: str = 'utf-8',
+    status: int = 200
+) -> Any:
 
-    def wrapper(func):
+    def wrapper(func: Any) -> Any:
         @functools.wraps(func)
-        async def wrapped(*args):
+        async def wrapped(*args: Any) -> web.StreamResponse:
             if asyncio.iscoroutinefunction(func):
                 coro = func
             else:
@@ -107,7 +138,10 @@ async def wrapped(*args):
 
 
 @web.middleware
-async def context_processors_middleware(request, handler):
+async def context_processors_middleware(
+    request: web.Request,
+    handler: Callable[[web.Request], Awaitable[web.StreamResponse]]
+) -> web.StreamResponse:
 
     if REQUEST_CONTEXT_KEY not in request:
         request[REQUEST_CONTEXT_KEY] = {}
@@ -116,5 +150,5 @@ async def context_processors_middleware(request, handler):
     return await handler(request)
 
 
-async def request_processor(request):
+async def request_processor(request: web.Request) -> Dict[str, web.Request]:
     return {'request': request}

aiohttp_jinja2/helpers.py

@@ -2,18 +2,22 @@
 useful context functions, see
 http://jinja.pocoo.org/docs/dev/api/#jinja2.contextfunction
 """
+from typing import Any, Dict, cast
+
 import jinja2
+from aiohttp import web
+from yarl import URL
 
 
-@jinja2.contextfunction
-def url_for(context, __route_name, **parts):
+@jinja2.contextfunction  # type: ignore
+def url_for(context: Dict[str, Any], __route_name: str, **parts: Any) -> URL:
     """Filter for generating urls.
 
     Usage: {{ url('the-view-name') }} might become "/path/to/view" or
     {{ url('item-details', id=123, query={'active': 'true'}) }}
     might become "/items/1?active=true".
     """
-    app = context['app']
+    app = cast(web.Application, context['app'])
 
     query = None
     if 'query_' in parts:
@@ -39,8 +43,8 @@ def url_for(context, __route_name, **parts):
     return url
 
 
-@jinja2.contextfunction
-def static_url(context, static_file_path):
+@jinja2.contextfunction  # type: ignore
+def static_url(context: Dict[str, Any], static_file_path: str) -> str:
     """Filter for generating urls for static files.
 
     NOTE: you'll need

aiohttp_jinja2/py.typed

@@ -0,0 +1 @@
+# marker

requirements-dev.txt

@@ -11,4 +11,5 @@ yarl==1.3.0
 multidict==4.5.2
 pytest-aiohttp==0.3.0
 pytest-sugar==0.9.2
+mypy==0.740
 -e .