uwsgi: enable http plugin and expose headers for SSL detection

Add the http plugin to the uWSGI build.

uWSGI enables HTTPS support in the http plugin only when OpenSSL headers
are detected at build time. Populate UWSGI_INCLUDES with the include
paths
of all build inputs so uwsgiconfig.py can discover OpenSSL and other
optional features correctly.

pkgs/by-name/uw/uwsgi/package.nix

@@ -6,6 +6,7 @@
   jansson,
   pcre2,
   libxcrypt,
+  openssl,
   expat,
   zlib,
   # plugins: list of strings, eg. [ "python3" ]
@@ -64,6 +65,12 @@ let
       ]
       ++ php-embed.unwrapped.buildInputs;
     })
+    (lib.nameValuePair "http" {
+      # usage: https://uwsgi-docs.readthedocs.io/en/latest/HTTP.html
+      # usage: https://uwsgi-docs.readthedocs.io/en/latest/HTTPS.html
+      path = "plugins/http";
+      inputs = [ openssl.dev ];
+    })
   ];
 
   getPlugin =
@@ -119,7 +126,11 @@ stdenv.mkDerivation (finalAttrs: {
     lib.optional withPAM "pam" ++ lib.optional withSystemd "systemd_logger"
   );
 
-  UWSGI_INCLUDES = lib.optionalString withCap "${libcap.dev}/include";
+  # UWSGI_INCLUDES environment variable required for "auto" plugins
+  # to be detected. See uwsgiconfig.py for more details.
+  UWSGI_INCLUDES = lib.concatStringsSep "," (
+    map (p: "${lib.getDev p}/include") finalAttrs.buildInputs
+  );
 
   passthru = {
     inherit python3;