parse and send HTTP/1 reason phrase

This change allows customized HTTP1 reason phrase to be used and
proxied.

4 files changed, 78 insertions, 2 deletions

diff --git a/.bleep b/.bleep
index f883866..2334b4d 100644
--- a/.bleep
+++ b/.bleep
@@ -1 +1 @@
-b5cb1b6f679bf1dcd136617b0212eb4f7c4bce84
\ No newline at end of file
+c6dc070f9cc16937943cc3b4d3299dbe3904fab8
\ No newline at end of file
diff --git a/pingora-core/src/protocols/http/v1/client.rs b/pingora-core/src/protocols/http/v1/client.rs
index 1dfb97a..aaa7d8c 100644
--- a/pingora-core/src/protocols/http/v1/client.rs
+++ b/pingora-core/src/protocols/http/v1/client.rs
@@ -249,6 +249,8 @@ impl HttpSession {
                         _ => Version::HTTP_09,
                     });
 
+                    response_header.set_reason_phrase(resp.reason)?;
+
                     let buf = buf.freeze();
 
                     for header in header_refs {
@@ -721,6 +723,20 @@ mod tests_stream {
     }
 
     #[tokio::test]
+    async fn read_response_custom_reason() {
+        init_log();
+        let input = b"HTTP/1.1 200 Just Fine\r\n\r\n";
+        let mock_io = Builder::new().read(&input[..]).build();
+        let mut http_stream = HttpSession::new(Box::new(mock_io));
+        let res = http_stream.read_response().await;
+        assert_eq!(input.len(), res.unwrap());
+        assert_eq!(
+            http_stream.resp_header().unwrap().get_reason_phrase(),
+            Some("Just Fine")
+        );
+    }
+
+    #[tokio::test]
     async fn read_response_default() {
         init_log();
         let input_header = b"HTTP/1.1 200 OK\r\n\r\n";
diff --git a/pingora-core/src/protocols/http/v1/server.rs b/pingora-core/src/protocols/http/v1/server.rs
index 7939ed4..d808506 100644
--- a/pingora-core/src/protocols/http/v1/server.rs
+++ b/pingora-core/src/protocols/http/v1/server.rs
@@ -1013,7 +1013,7 @@ fn http_resp_header_to_buf(
     let status = resp.status;
     buf.put_slice(status.as_str().as_bytes());
     buf.put_u8(b' ');
-    let reason = status.canonical_reason();
+    let reason = resp.get_reason_phrase();
     if let Some(reason_buf) = reason {
         buf.put_slice(reason_buf.as_bytes());
     }
@@ -1382,6 +1382,21 @@ mod tests_stream {
     }
 
     #[tokio::test]
+    async fn write_custom_reason() {
+        let wire = b"HTTP/1.1 200 Just Fine\r\nFoo: Bar\r\n\r\n";
+        let mock_io = Builder::new().write(wire).build();
+        let mut http_stream = HttpSession::new(Box::new(mock_io));
+        let mut new_response = ResponseHeader::build(StatusCode::OK, None).unwrap();
+        new_response.set_reason_phrase(Some("Just Fine")).unwrap();
+        new_response.append_header("Foo", "Bar").unwrap();
+        http_stream.update_resp_headers = false;
+        http_stream
+            .write_response_header_ref(&new_response)
+            .await
+            .unwrap();
+    }
+
+    #[tokio::test]
     async fn write_informational() {
         let wire = b"HTTP/1.1 100 Continue\r\n\r\nHTTP/1.1 200 OK\r\nFoo: Bar\r\n\r\n";
         let mock_io = Builder::new().write(wire).build();
diff --git a/pingora-http/src/lib.rs b/pingora-http/src/lib.rs
index b616743..74dee53 100644
--- a/pingora-http/src/lib.rs
+++ b/pingora-http/src/lib.rs
@@ -288,6 +288,8 @@ pub struct ResponseHeader {
     base: RespParts,
     // an ordered header map to store the original case of each header name
     header_name_map: Option<CaseMap>,
+    // the reason phrase of the response, if unset, a default one will be used
+    reason_phrase: Option<String>,
 }
 
 impl AsRef<RespParts> for ResponseHeader {
@@ -309,6 +311,7 @@ impl Clone for ResponseHeader {
         Self {
             base: self.as_owned_parts(),
             header_name_map: self.header_name_map.clone(),
+            reason_phrase: self.reason_phrase.clone(),
         }
     }
 }
@@ -319,6 +322,7 @@ impl From<RespParts> for ResponseHeader {
         Self {
             base: parts,
             header_name_map: None,
+            reason_phrase: None,
         }
     }
 }
@@ -350,6 +354,7 @@ impl ResponseHeader {
         ResponseHeader {
             base,
             header_name_map: None,
+            reason_phrase: None,
         }
     }
 
@@ -443,6 +448,27 @@ impl ResponseHeader {
         self.base.version = version
     }
 
+    /// Set the HTTP reason phase. If `None`, a default reason phase will be used
+    pub fn set_reason_phrase(&mut self, reason_phrase: Option<&str>) -> Result<()> {
+        // No need to allocate memory to store the phrase if it is the default one.
+        if reason_phrase == self.base.status.canonical_reason() {
+            self.reason_phrase = None;
+            return Ok(());
+        }
+
+        // TODO: validate it "*( HTAB / SP / VCHAR / obs-text )"
+        self.reason_phrase = reason_phrase.map(str::to_string);
+        Ok(())
+    }
+
+    /// Get the HTTP reason phase. If [Self::set_reason_phrase()] is never called
+    /// or set to `None`, a default reason phase will be used
+    pub fn get_reason_phrase(&self) -> Option<&str> {
+        self.reason_phrase
+            .as_deref()
+            .or_else(|| self.base.status.canonical_reason())
+    }
+
     /// Clone `self` into [http::response::Parts].
     pub fn as_owned_parts(&self) -> RespParts {
         clone_resp_parts(&self.base)
@@ -668,4 +694,23 @@ mod tests {
         assert_eq!("Hello�World", req.uri.path_and_query().unwrap());
         assert_eq!(raw_path, req.raw_path());
     }
+
+    #[test]
+    fn test_reason_phrase() {
+        let mut resp = ResponseHeader::new(None);
+        let reason = resp.get_reason_phrase().unwrap();
+        assert_eq!(reason, "OK");
+
+        resp.set_reason_phrase(Some("FooBar")).unwrap();
+        let reason = resp.get_reason_phrase().unwrap();
+        assert_eq!(reason, "FooBar");
+
+        resp.set_reason_phrase(Some("OK")).unwrap();
+        let reason = resp.get_reason_phrase().unwrap();
+        assert_eq!(reason, "OK");
+
+        resp.set_reason_phrase(None).unwrap();
+        let reason = resp.get_reason_phrase().unwrap();
+        assert_eq!(reason, "OK");
+    }
 }