native: handshake: Support redirection

Author: ifdario

src/lib.rs

@@ -130,6 +130,16 @@ pub enum WebSocketError {
     #[cfg(not(target_arch = "wasm32"))]
     InvalidStatusCode(u16),
 
+    /// Server responded with a redirect status code.
+    #[error("Redirected with status code {status_code} to {location}")]
+    #[cfg(not(target_arch = "wasm32"))]
+    Redirected {
+        /// The HTTP status code (e.g. 301, 302, 307, 308).
+        status_code: u16,
+        /// The target location from the `Location` header.
+        location: String,
+    },
+
     /// Missing or invalid "Upgrade: websocket" header.
     #[error("Invalid upgrade header")]
     #[cfg(not(target_arch = "wasm32"))]
@@ -247,6 +257,7 @@ impl WebSocketError {
         matches!(
             self,
             Self::InvalidStatusCode(_)
+                | Self::Redirected { .. }
                 | Self::InvalidUpgradeHeader
                 | Self::InvalidConnectionHeader
                 | Self::InvalidSecWebsocketVersion

src/native/mod.rs

@@ -1349,6 +1349,20 @@ fn verify_reqwest(response: &reqwest::Response, options: Options) -> Result<Nego
 }
 
 fn verify(response: &Response<Incoming>, options: Options) -> Result<Negotiation> {
+    // Detect HTTP redirects before checking for 101.
+    if response.status().is_redirection() {
+        let location = response
+            .headers()
+            .get(header::LOCATION)
+            .and_then(|v| v.to_str().ok())
+            .unwrap_or("")
+            .to_string();
+        return Err(WebSocketError::Redirected {
+            status_code: response.status().as_u16(),
+            location,
+        });
+    }
+
     if response.status() != StatusCode::SWITCHING_PROTOCOLS {
         return Err(WebSocketError::InvalidStatusCode(
             response.status().as_u16(),