Fix request pseudo-header construction for CONNECT & OPTION methods

CONNECT & OPTIONS request has special requirements regarding :path & :scheme pseudo-header which were not met.

Construction of pseudo-header was fixed to not include :path & :scheme fields for CONNECT method.
Empty :path field for OPTIONS requests now translates to '*' value sent in :path field.

CONNECT request changes were tested against server based on hyper 1.2.

Author: mstyura

src/frame/headers.rs

@@ -554,32 +554,44 @@ impl Pseudo {
     pub fn request(method: Method, uri: Uri, protocol: Option<Protocol>) -> Self {
         let parts = uri::Parts::from(uri);
 
-        let mut path = parts
-            .path_and_query
-            .map(|v| BytesStr::from(v.as_str()))
-            .unwrap_or(BytesStr::from_static(""));
-
-        match method {
-            Method::OPTIONS | Method::CONNECT => {}
-            _ if path.is_empty() => {
-                path = BytesStr::from_static("/");
-            }
-            _ => {}
-        }
+        let (scheme, path) = if method == Method::CONNECT { 
+            // CONNECT requests MUST NOT include :scheme & :path pseudo-header fields
+            // See: https://datatracker.ietf.org/doc/html/rfc9113#section-8.5
+            (None, None)
+        } else {
+            let path = parts
+                .path_and_query
+                .map(|v| BytesStr::from(v.as_str()))
+                .unwrap_or(BytesStr::from_static(""));
+
+            let path = if !path.is_empty() {
+                path
+            } else {
+                if method == Method::OPTIONS {
+                    // An OPTIONS request for an "http" or "https" URI that does not include a path component; 
+                    // these MUST include a ":path" pseudo-header field with a value of '*' (see Section 7.1 of [HTTP]).
+                    // See: https://datatracker.ietf.org/doc/html/rfc9113#section-8.3.1
+                    // TODO: Validate URI is "http" or "https".
+                    BytesStr::from_static("*")
+                } else {
+                    BytesStr::from_static("/")
+                }
+            };
+
+            (parts.scheme, Some(path).filter(|p| !p.is_empty()))
+        };
 
         let mut pseudo = Pseudo {
             method: Some(method),
             scheme: None,
             authority: None,
-            path: Some(path).filter(|p| !p.is_empty()),
+            path,
             protocol,
             status: None,
         };
 
         // If the URI includes a scheme component, add it to the pseudo headers
-        //
-        // TODO: Scheme must be set...
-        if let Some(scheme) = parts.scheme {
+        if let Some(scheme) = scheme {
             pseudo.set_scheme(scheme);
         }