Be able to force the client information

To be able to generate correct URL when we debug with pserve behind a
reverse proxy.

README.md

@@ -665,3 +665,10 @@ To make a release:
 - Tag the GIT commit.
 - Add the new branch name in the `.github/workflows/rebuild.yaml` and
   `.github/workflows/audit.yaml` files.
+
+## Pserve
+
+Pserve will not set the headers in the environment then if you are behind a reverse proxy, you will have
+wrong values in client information, you can force them by using the environment variables:
+`C2CWSGIUTILS_FORCE_PROTO`, `C2CWSGIUTILS_FORCE_HOST` `C2CWSGIUTILS_FORCE_SERVER_NAME` and
+`C2CWSGIUTILS_FORCE_REMOTE_ADDR`.

c2cwsgiutils/client_info.py

@@ -1,3 +1,4 @@
+import os
 import re
 from typing import Any, Callable, Dict
 
@@ -22,6 +23,15 @@ def __call__(self, environ: Dict[str, str], start_response: Any) -> Any:
         else:
             _handle_others(environ)
 
+        if "C2CWSGIUTILS_FORCE_PROTO" in os.environ:
+            environ["wsgi.url_scheme"] = os.environ["C2CWSGIUTILS_FORCE_PROTO"]
+        if "C2CWSGIUTILS_FORCE_HOST" in os.environ:
+            environ["HTTP_HOST"] = os.environ["C2CWSGIUTILS_FORCE_HOST"]
+        if "C2CWSGIUTILS_FORCE_SERVER_NAME" in os.environ:
+            environ["SERVER_NAME"] = os.environ["C2CWSGIUTILS_FORCE_SERVER_NAME"]
+        if "C2CWSGIUTILS_FORCE_REMOTE_ADDR" in os.environ:
+            environ["REMOTE_ADDR"] = os.environ["C2CWSGIUTILS_FORCE_REMOTE_ADDR"]
+
         return self._application(environ, start_response)