Deprecate missing format inference on RPC protocol (#4729)

Co-authored-by: Tobie Morgan Hitchcock <tobie@surrealdb.com>

sdk/src/api/engine/remote/ws/mod.rs

@@ -24,6 +24,7 @@ use uuid::Uuid;
 pub(crate) const PATH: &str = "rpc";
 const PING_INTERVAL: Duration = Duration::from_secs(5);
 const REVISION_HEADER: &str = "revision";
+const BINCODE_HEADER: &str = "bincode";
 
 enum RequestEffect {
 	/// Completing this request sets a variable to a give value.

sdk/src/api/engine/remote/ws/native.rs

@@ -80,6 +80,10 @@ pub(crate) async fn connect(
 		request
 			.headers_mut()
 			.insert(SEC_WEBSOCKET_PROTOCOL, HeaderValue::from_static(super::REVISION_HEADER));
+	} else {
+		request
+			.headers_mut()
+			.insert(SEC_WEBSOCKET_PROTOCOL, HeaderValue::from_static(super::BINCODE_HEADER));
 	}
 
 	#[cfg(any(feature = "native-tls", feature = "rustls"))]

src/err/mod.rs

@@ -2,7 +2,6 @@ use crate::cli::abstraction::auth::Error as SurrealAuthError;
 use axum::response::{IntoResponse, Response};
 use axum::Error as AxumError;
 use axum::Json;
-use axum_extra::typed_header::TypedHeaderRejection;
 use base64::DecodeError as Base64Error;
 use http::{HeaderName, StatusCode};
 use reqwest::Error as ReqwestError;
@@ -38,7 +37,7 @@ pub enum Error {
 	OperationUnsupported,
 
 	#[error("There was a problem parsing the header {0}: {1}")]
-	InvalidHeader(HeaderName, TypedHeaderRejection),
+	InvalidHeader(HeaderName, String),
 
 	#[error("There was a problem with the database: {0}")]
 	Db(#[from] SurrealError),

src/net/headers/mod.rs

@@ -58,7 +58,7 @@ where
 		Ok(TypedHeader(val)) => Ok(Some(val.to_string())),
 		Err(e) => match e.reason() {
 			TypedHeaderRejectionReason::Missing => Ok(None),
-			_ => Err(Error::InvalidHeader(H::name().to_owned(), e)),
+			_ => Err(Error::InvalidHeader(H::name().to_owned(), e.to_string())),
 		},
 	}
 }

src/net/rpc.rs

@@ -22,8 +22,8 @@ use axum::{
 use axum_extra::headers::Header;
 use axum_extra::TypedHeader;
 use bytes::Bytes;
+use http::header::SEC_WEBSOCKET_PROTOCOL;
 use http::HeaderMap;
-use http::HeaderValue;
 use surrealdb::dbs::Session;
 use surrealdb::kvs::Datastore;
 use surrealdb::rpc::format::Format;
@@ -54,6 +54,13 @@ async fn get_handler(
 	State(rpc_state): State<Arc<RpcState>>,
 	headers: HeaderMap,
 ) -> Result<impl IntoResponse, impl IntoResponse> {
+	// Check that a valid header has been specified
+	if headers.get(SEC_WEBSOCKET_PROTOCOL).is_none() {
+		warn!("A connection was made without a specified protocol.");
+		warn!("Automatic inference of the protocol format is deprecated in SurrealDB 2.0 and will be removed in SurrealDB 3.0.");
+		warn!("Please upgrade any client to ensure that the connection format is specified.");
+	}
+
 	// Check if there is a connection id header specified
 	let id = match headers.get(SurrealId::name()) {
 		// Use the specific SurrealDB id header when provided
@@ -119,9 +126,9 @@ async fn handle_socket(
 	id: Uuid,
 ) {
 	// Check if there is a WebSocket protocol specified
-	let format = match ws.protocol().map(HeaderValue::to_str) {
+	let format = match ws.protocol().and_then(|h| h.to_str().ok()) {
 		// Any selected protocol will always be a valie value
-		Some(protocol) => protocol.unwrap().into(),
+		Some(protocol) => protocol.into(),
 		// No protocol format was specified
 		_ => Format::None,
 	};