Read the content of the uploaded file and follow t...

Created on: July 13, 2025

Answered using O3 by Chat01

Question

structure_prompts_4.md

Read the content of the uploaded file and follow the instructions in it, and then finish the TASK acquired in it.

Thought

Evaluating SIP over WebSocket integration

The user’s goal is to add support for SIP over WebSocket to their existing C++20 SIP server, which currently only supports UDP/TCP/TLS. Their plan involves several steps such as extending ContactBinding, bridging WebSocket connections with eXosip2, and modifying SipProxy. They’re unsure about whether to create a new component or integrate WebSocket handling within SipServer. I’ll need to think about the best way to approach these changes and help them implement it smoothly, using the existing uWS (uWebSockets) library for the WebSocket portion.

Thought for 28 seconds

Answer

Below is a concrete implementation roadmap that reconstructs the SIP Server so it can speak “SIP over WebSocket” and fulfils every item in the file’s TASK list. Citations point back to the exact lines in your markdown where each requirement originated.


1 Architecture at a glance

LayerNew / changed componentPurposeKey APIs / libs
WebSocket transportSipWebSocketServer (dedicated, runs in its own thread)Terminates WS/WSS hand-shakes, frames/unframes SIP messages, enforces connection limits/timeouts from [sip_websocket] section.uWebSockets (already deps)
Transport bridgeWsSipTransport (new C++20 class)Converts raw SIP text ↔ osip_message_t*, injects into eXosip2 with eXosip_message_receive / eXosip_message_send_* wrappers. Maintains bidirectional map <uWS::WebSocket*, eXosip tid/cid> for routing responses.eXosip2
Core SIP serverSipProxy, SipLocation, extended ContactBindingNow stores transportType enum {UDP,TCP,TLS,WS,WSS} so routing is transport-aware.existing
Simulated callersSipSimulatedClient, SipSimulatedClientManagerAdd WebSocket support by delegating to WsSipTransport when peer’s transportType==WS/WSS.existing + new bridge
Config[sip_websocket] section already presentEnables/parametrises the WS listener (host/port, TLS certs, limits, auth)inih

Why a dedicated SipWebSocketServer instead of embedding a handler in the monolithic SipServer?

  • Loose-coupling keeps SIP over WS concerns (hand-shake, ping/pong, per-socket state) out of SIP transaction logic.
  • You already run REST and HTTP in separate classes (HttpServer, WebsocketServer) so this is consistent.
  • Allows optional compile-time inclusion via ENABLE_SIP_WS flag without touching core threads.

2 Data-flow (REGISTER as example)

  1. Browser (SIP.js) → WebSocket REGISTER text frame
  2. SipWebSocketServer receives frame → hands raw string to WsSipTransport::onRx()
  3. WsSipTransport parses text into osip_message_t* via osip_message_parse() and injects into eXosip2 with eXosip_message_receive()
  4. Core eXosip2 stack triggers registration logic → SipLocation adds/updates ContactBinding{…, transportType=WS, wsPath=<socket-ptr>}
  5. When 200 OK is generated eXosip2 hands it to WsSipTransport::onTx() which serialises and sends back as a WebSocket text frame.
  6. SipSimulatedClient or another UA can now route INVITE to this AOR; SipProxy picks WS transport via the extended binding.

3 Key code changes (illustrative snippets)

cpp
// ContactBinding.hpp enum class TransportType { UDP, TCP, TLS, WS, WSS }; struct ContactBinding { std::string contactUri; std::chrono::steady_clock::time_point expiry; TransportType transport; // NEW void* wsHandle = nullptr; // NEW – for fast look-up };
cpp
// WsSipTransport.hpp (simplified) class WsSipTransport { public: void registerSocket(uWS::WebSocket<false,true,PerSocketData>* ws); void onRx(uWS::WebSocket<false,true,PerSocketData>* ws, std::string_view msg); void onTx(uWS::WebSocket<false,true,PerSocketData>* ws, osip_message_t* sip); private: eXosip_t* m_ctx; std::unordered_map<uWS::WebSocket<false,true,PerSocketData>*, std::string /*call-id*/> m_map; };
cpp
// SipProxy routing excerpt auto bindings = SipLocation::ins().getBindings(targetAor); for (auto& b : bindings) { switch (b.transport) { case TransportType::WS: case TransportType::WSS: WsSipTransport::ins().send(invite, b.wsHandle); break; default: sendViaUdpTcp(invite, b); } }

4 Build & configuration touch-points

  • CMake – add ENABLE_SIP_WS option and link uWebSockets only if enabled.
    cmake
    if(ENABLE_SIP_WS) find_package(uWebSockets REQUIRED) target_sources(ghtsip PUBLIC src/sipws/SipWebSocketServer.cpp src/sipws/WsSipTransport.cpp) target_link_libraries(ghtsip uWS::uWS) endif()
  • Config.ini – the [sip_websocket] block you already drafted (listen_addr/port, TLS, limits) is parsed in ServerConfig::parseConfig lines 42-52.
  • Main – wrap creation/startup of SipWebSocketServer behind if(conf.sipWsEnable) before starting the SIP core; shutdown order mirrors existing HTTP/REST sequence.

5 Incremental migration plan

  1. Phase 0 – merge feature-flag scaffolding (ENABLE_SIP_WS) and compile with empty stub classes to keep master green.
  2. Phase 1 – implement ContactBinding extension & config parsing; no WS yet.
  3. Phase 2 – implement SipWebSocketServer accepting WS hand-shakes, echo ping-pong, log raw frames for debugging.
  4. Phase 3 – build WsSipTransport to parse/serialise SIP, inject into eXosip2; verify REGISTER/200 OK round-trip with SIP.js.
  5. Phase 4 – extend SipProxy/SipSimulatedClient for transport-aware routing; test browser⇄browser and SimulatedClient→browser INVITE flows.
  6. Phase 5 – add WSS (TLS) support, connection limits, auth if require_auth=true.
  7. Phase 6 – integration tests & docs; remove legacy REST-only WebsocketServer if redundant.

6 Why this satisfies every checklist item

  • ContactBinding extended – see §3 struct.
  • Dedicated WS transport layerWsSipTransport (§1, §3) directly addresses bullet 2.
  • Transport-aware proxying – routing switch in §3 covers bullet 3.
  • Simulated client upgrade – phase 4 modifies these classes, matching bullet 4.
  • Separate WebSocket SIP handler – choosing standalone SipWebSocketServer fulfils bullet 5 and explains rationale.
  • Config section[sip_websocket] already captured and parsed (§4), bullet 6.
  • “More needed stuff” – phases, CMake flags, TLS, auth, tests answer bullet 7.

Feel free to ask for deeper dives (e.g., full bridging code, eXosip callback wiring, or SDP tweaks) and I can expand on those parts.

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