Add grpc web layer

prover/Cargo.toml

@@ -6,7 +6,8 @@ edition = "2024"
 [dependencies]
 clap = { version = "4.5.37", features = ["derive"] }
 tonic = { version = "0.13", features = ["gzip"] }
-tonic-reflection = "0.13"
+tonic-reflection = "*"
+tonic-web = "*"
 prost = "0.13"
 tokio = { version = "1", features = ["macros", "rt-multi-thread"] }
 tracing-subscriber = { version = "0.3.19", features = ["env-filter"] }
@@ -24,6 +25,8 @@ bytesize = "2.0.1"
 rln_proof = { path = "../rln_proof" }
 chrono = "0.4.41"
 parking_lot = "0.12.3"
+tower-http = { version = "0.6.4", features = ["cors"] }
+http = "*"
 
 [build-dependencies]
 tonic-build = "*"

prover/src/grpc_service.rs

@@ -29,6 +29,11 @@ use tonic::{
     transport::Server,
     // codec::CompressionEncoding
 };
+use tonic_web::{
+    GrpcWebLayer,
+};
+use tower_http::cors::{Any, CorsLayer};
+use http::Method;
 use tracing::{
     debug,
     // error,
@@ -206,7 +211,10 @@ impl RlnProver for ProverService {
         &self,
         _request: Request<RegisterUserRequest>,
     ) -> Result<Response<RegisterUserReply>, Status> {
-        todo!()
+        let reply = RegisterUserReply {
+            status: 0
+        };
+        Ok(Response::new(reply))
     }
 
     type GetProofsStream = ReceiverStream<Result<RlnProof, Status>>;
@@ -278,6 +286,20 @@ impl GrpcProverService {
             //.send_compressed(CompressionEncoding::Gzip)
             ;
 
+        // CORS
+        let cors = CorsLayer::new()
+            // Allow `GET`, `POST` and `OPTIONS` when accessing the resource
+            .allow_methods([
+                Method::GET,
+                // http POST && OPTIONS not required for grpc-web
+                // Method::POST,
+                // Method::OPTIONS
+            ])
+            // Allow requests from any origin
+            // FIXME: config?
+            .allow_origin(Any)
+            .allow_headers(Any);
+
         Server::builder()
             // service protection && limits
             // limits: connection
@@ -288,9 +310,11 @@ impl GrpcProverService {
             .max_frame_size(PROVER_SERVICE_HTTP2_MAX_FRAME_SIZE.as_u64() as u32)
             // perf: tcp
             .tcp_nodelay(true)
-            // No http 1
-            .accept_http1(false)
+            // http 1 layer required for GrpcWebLayer
+            .accept_http1(true)
             // services
+            .layer(cors)
+            .layer(GrpcWebLayer::new())
             .add_service(reflection_service)
             .add_service(r)
             .serve(self.addr)

prover/src/main.rs

@@ -1,5 +1,5 @@
 mod args;
-mod epoch_service;
+// mod epoch_service;
 mod error;
 mod grpc_service;
 mod registry;