Websocket (wss)-Based Span Processor for Browser & Node Telemetry

[clayroach]

What is the problem this feature would solve?

Browser applications need to export telemetry data, but the current options have limitations:

1. HTTP/OTLP (@opentelemetry/exporter-trace-otlp-http)

   • CORS configuration required on collector
   • Each span batch creates a new request (DevTools noise)
   • No streaming capability
   • Higher overhead for frequent small payloads

2. No official WebSocket exporter exists

   • OTEP-0099 notes: "Experimental implementation of OTLP over WebSocket transport has shown that it typically has better performance than plain HTTP"
   • Left as "future consideration" due to library availability concerns
   • Community solutions are fragmented and minimally maintained

3. Standard OTel BatchSpanProcessor limitations

   • Uses setTimeout/setInterval and unmanaged promises
   • Does not participate in Effect's Scope or fiber management
   • No backpressure handling

What is the feature you are proposing to solve the problem?

Add a SocketSpanProcessor to @effect/opentelemetry that leverages @effect/platform's abstract Socket interface. This provides Effect-native telemetry export with proper error handling, automatic reconnection, and resource management—working across Browser, Node, Bun, and any platform with a Socket implementation.

What alternatives have you considered?

1. Use HTTP Exporter Only

The existing @opentelemetry/exporter-trace-otlp-http works but:

• CORS configuration is an operational burden
• No streaming means higher latency for real-time use cases
• DevTools network tab becomes noisy

2. Build a Custom Protocol

Could define a minimal "just span data" format but:

• Fragments the ecosystem further
• Loses compatibility with OTLP tooling
• More work for marginal gains

3. Build Outside Effect Ecosystem

Could publish as separate package but:

• Loses Effect integration benefits (typed errors, scheduling, resources)
• Misses opportunity to showcase platform abstractions