http_protocol: implement axum IntoResponse, use in http_private

aquatic_http_protocol/Cargo.toml

@@ -22,8 +22,12 @@ name = "bench_announce_response_to_bytes"
 path = "benches/bench_announce_response_to_bytes.rs"
 harness = false
 
+[features]
+with-axum = ["axum"]
+
 [dependencies]
 anyhow = "1"
+axum = { version = "0.5", optional = true, default-features = false }
 hex = { version = "0.4", default-features = false }
 httparse = "1"
 itoa = "1"

aquatic_http_protocol/src/response.rs

@@ -112,6 +112,21 @@ impl AnnounceResponse {
     }
 }
 
+#[cfg(feature = "with-axum")]
+impl axum::response::IntoResponse for AnnounceResponse {
+    fn into_response(self) -> axum::response::Response {
+        let mut response_bytes = Vec::with_capacity(128);
+
+        self.write(&mut response_bytes).unwrap();
+
+        (
+            [("Content-type", "text/plain; charset=utf-8")],
+            response_bytes,
+        )
+            .into_response()
+    }
+}
+
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct ScrapeResponse {
     /// BTreeMap instead of HashMap since keys need to be serialized in order
@@ -142,6 +157,21 @@ impl ScrapeResponse {
     }
 }
 
+#[cfg(feature = "with-axum")]
+impl axum::response::IntoResponse for ScrapeResponse {
+    fn into_response(self) -> axum::response::Response {
+        let mut response_bytes = Vec::with_capacity(128);
+
+        self.write(&mut response_bytes).unwrap();
+
+        (
+            [("Content-type", "text/plain; charset=utf-8")],
+            response_bytes,
+        )
+            .into_response()
+    }
+}
+
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct FailureResponse {
     #[serde(rename = "failure reason")]
@@ -170,6 +200,21 @@ impl FailureResponse {
     }
 }
 
+#[cfg(feature = "with-axum")]
+impl axum::response::IntoResponse for FailureResponse {
+    fn into_response(self) -> axum::response::Response {
+        let mut response_bytes = Vec::with_capacity(64);
+
+        self.write(&mut response_bytes).unwrap();
+
+        (
+            [("Content-type", "text/plain; charset=utf-8")],
+            response_bytes,
+        )
+            .into_response()
+    }
+}
+
 #[derive(Debug, Clone, Serialize, Deserialize)]
 #[serde(untagged)]
 pub enum Response {
@@ -191,6 +236,17 @@ impl Response {
     }
 }
 
+#[cfg(feature = "with-axum")]
+impl axum::response::IntoResponse for Response {
+    fn into_response(self) -> axum::response::Response {
+        match self {
+            Self::Announce(r) => r.into_response(),
+            Self::Scrape(r) => r.into_response(),
+            Self::Failure(r) => r.into_response(),
+        }
+    }
+}
+
 #[cfg(test)]
 impl quickcheck::Arbitrary for ResponsePeer<Ipv4Addr> {
     fn arbitrary(g: &mut quickcheck::Gen) -> Self {