Standalone Server

GQLXY includes an opt-in HTTP/WebSocket/SSE server backed by Oat++. It exposes all four GraphQL transports on a single endpoint — similar to Apollo Server's startStandaloneServer.

Prerequisites

The standalone server requires the standalone-server vcpkg feature. This is enabled by default in the CMake presets. When building manually, add:

cmake -DBUILD_STANDALONE_SERVER=ON -DVCPKG_MANIFEST_FEATURES="standalone-server" ...

Quick start

#include <gqlxy/schema.h>
#include <gqlxy/server/standalone_server.h>

using namespace gqlxy;
using namespace gqlxy::server;

int main() {
    Schema schema({
        .typeDefs  = R"(
            type Query {
                hello: String
            }
        )",
        .resolvers = {
            {"Query", Resolver{
                {"hello", "Hello, world!"}
            }}
        }
    });

    StandaloneServer server({
        .schema = schema,
        .port = 4000
    });

    std::cout << "🚀 Server ready at " << server.GetUrl() << std::endl;
    server.Start();
}

Non-blocking usage

StandaloneServer server({
    .schema = schema,
    .port = 4000
});
server.StartAsync();
// ... do other work ...
server.Stop();

Supported transports

All transports are served on the same path (default /graphql).

HTTP

• POST /graphql — application/json body with query, variables, operationName
• GET /graphql?query=... — for read-only operations
• Response Content-Type: application/graphql-response+json
• CORS preflight (OPTIONS) handled automatically

WebSocket — graphql-transport-ws

The modern protocol used by Apollo Client 3+, Relay, and Insomnia.

Messages: connection_init / connection_ack, subscribe, next, error, complete, ping / pong.

WebSocket — graphql-ws (legacy)

The legacy subscriptions-transport-ws protocol.

Messages: connection_init / connection_ack, start, data, stop, complete, connection_terminate.

The protocol is auto-detected from the first message (start → legacy, subscribe → modern).

Server-Sent Events (SSE)

Streaming via Accept: text/event-stream on the same path. Works through firewalls and proxies that block WebSockets. Events: connection_ack, next, complete.