imrove wsgi adapter to match standard

Author: WilliamBergamin

slack_bolt/adapter/wsgi/handler.py

@@ -1,6 +1,10 @@
-from typing import Any, Callable, Dict, Iterable, List, Tuple
+from typing import TYPE_CHECKING, Iterable
 
 from slack_bolt import App
+
+if TYPE_CHECKING:
+    from wsgiref.types import StartResponse, WSGIEnvironment
+
 from slack_bolt.adapter.wsgi.http_request import WsgiHttpRequest
 from slack_bolt.adapter.wsgi.http_response import WsgiHttpResponse
 from slack_bolt.request import BoltRequest
@@ -69,14 +73,17 @@ def _get_http_response(self, request: WsgiHttpRequest) -> WsgiHttpResponse:
 
     def __call__(
         self,
-        environ: Dict[str, Any],
-        start_response: Callable[..., Any],
+        environ: "WSGIEnvironment",
+        start_response: "StartResponse",
     ) -> Iterable[bytes]:
         request = WsgiHttpRequest(environ)
-        if "HTTP" in request.protocol:
+        if request.protocol.startswith("HTTP"):
             response: WsgiHttpResponse = self._get_http_response(
                 request=request,
             )
-            start_response(response.status, response.get_headers())
-            return response.get_body()
-        raise TypeError(f"Unsupported SERVER_PROTOCOL: {request.protocol}")
+        else:
+            response = WsgiHttpResponse(
+                status=400, headers={"content-type": ["text/plain;charset=utf-8"]}, body="Bad Request"
+            )
+        start_response(response.status, response.get_headers())
+        return response.get_body()

slack_bolt/adapter/wsgi/http_request.py

@@ -1,4 +1,7 @@
-from typing import Any, Dict, Sequence, Union
+from typing import TYPE_CHECKING, Dict, Sequence, Union
+
+if TYPE_CHECKING:
+    from wsgiref.types import WSGIEnvironment
 
 from .internals import ENCODING
 
@@ -12,7 +15,7 @@ class WsgiHttpRequest:
 
     __slots__ = ("method", "path", "query_string", "protocol", "environ")
 
-    def __init__(self, environ: Dict[str, Any]):
+    def __init__(self, environ: "WSGIEnvironment"):
         self.method: str = environ.get("REQUEST_METHOD", "GET")
         self.path: str = environ.get("PATH_INFO", "")
         self.query_string: str = environ.get("QUERY_STRING", "")
@@ -33,5 +36,5 @@ def get_headers(self) -> Dict[str, Union[str, Sequence[str]]]:
     def get_body(self) -> str:
         if "wsgi.input" not in self.environ:
             return ""
-        content_length = int(self.environ.get("CONTENT_LENGTH", 0))
+        content_length = int(self.environ.get("CONTENT_LENGTH") or 0)
         return self.environ["wsgi.input"].read(content_length).decode(ENCODING)

slack_bolt/adapter/wsgi/http_response.py

@@ -1,5 +1,5 @@
 from http import HTTPStatus
-from typing import Dict, Iterable, List, Sequence, Tuple
+from typing import Dict, Iterable, List, Optional, Sequence, Tuple
 
 from .internals import ENCODING
 
@@ -13,18 +13,19 @@ class WsgiHttpResponse:
 
     __slots__ = ("status", "_headers", "_body")
 
-    def __init__(self, status: int, headers: Dict[str, Sequence[str]] = {}, body: str = ""):
+    def __init__(self, status: int, headers: Optional[Dict[str, Sequence[str]]] = None, body: str = ""):
         _status = HTTPStatus(status)
         self.status = f"{_status.value} {_status.phrase}"
-        self._headers = headers
+        self._headers = headers or {}
         self._body = bytes(body, ENCODING)
 
     def get_headers(self) -> List[Tuple[str, str]]:
         headers: List[Tuple[str, str]] = []
-        for key, value in self._headers.items():
+        for key, values in self._headers.items():
             if key.lower() == "content-length":
                 continue
-            headers.append((key, value[0]))
+            for v in values:
+                headers.append((key, v))
 
         headers.append(("content-length", str(len(self._body))))
         return headers