# Sgcwebsockets Protocols > sgcWebSockets Subprotocols - Skill: `esegece-com/sgcwebsockets-protocols` (Agent Skill, multi-file: 182 files) - Install (CLI): `npx skillmds@latest add esegece-com/sgcwebsockets-protocols` - Raw SKILL.md: https://api.skillmd.com/api/skills/esegece-com/sgcwebsockets-protocols/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Coding & Dev Tools - Author: esegece-com (https://skillmd.com/u/esegece-com) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/esegece-com/sgcwebsockets-protocols --- # sgcWebSockets Subprotocols These are the subprotocols eSeGeCe ships itself, as opposed to the third-party broker protocols in `sgcwebsockets-mq`. They come in client and server pairs, so both ends of the conversation are components you drop on a form, and the wire format is handled for you. Use these when you control both ends. If you have to interoperate with someone else's broker, you want `sgcwebsockets-mq` instead. ## When to use this skill - Publish/subscribe over channels between your own Delphi client and server - Call a method on the server and get a result back, over the same socket - Keep a client-side dataset in step with a server-side one - Send files over an existing WebSocket connection, with delivery guarantees - Track who is present in a channel, and invite people to it - Encrypt messages end to end so the server cannot read them - Consume a Lightstreamer feed ## Install and uses clause All fifteen live in one unit, alongside the transport and connection classes: ```pascal uses sgcWebSocket, // TsgcWebSocketClient / TsgcWebSocketServer sgcWebSocket_Protocols, // the protocol components in this skill sgcWebSocket_Classes, // TsgcWSConnection, handed to every event sgcWebSocket_Types; // the enumerations ``` ## The binding rule A protocol component is inert until it is attached to a transport. Client-side protocols take a client, server-side protocols take a server: ```pascal FProtocolClient.Client := FWebSocketClient; // TsgcWSComponent_WSClient FProtocolServer.Server := FWebSocketServer; // TsgcWSComponent_Server ``` One protocol per transport, with one exception. The broker pair exists to lift that restriction: `TsgcWSPClient_broker` and `TsgcWSPServer_broker` accept other protocol components through `RegisterProtocol`, so several protocols share one connection. Components built to be brokered expose a `Broker` property to point back at it, which is how, for example, the MQTT client rides alongside others. ## Before you start, ask the developer Use a structured question tool if your host has one, for example Claude Code's `AskUserQuestion`. Otherwise ask in chat: 1. **Do you control both ends?** If the other end is someone else's broker, these components are the wrong answer, and the right skill is `sgcwebsockets-mq`. 2. **Which protocol?** They are not interchangeable. Pub/sub plus RPC is `sgc`, file transfer is `Files`, dataset sync is `Dataset`, and so on. 3. **More than one protocol on one connection?** That needs the broker pair. Retrofitting it later means rewiring both ends. 4. **WAMP version?** `TsgcWSPClient_WAMP` here is WAMP v1. WAMP2 is a different component and lives in `sgcwebsockets-mq`. ## Components in this skill | Pair | What it does | | --- | --- | | `TsgcWSPClient_sgc` / `TsgcWSPServer_sgc` | The general purpose one: channels, publish, subscribe, broadcast, and RPC | | `TsgcWSPClient_broker` / `TsgcWSPServer_broker` | Multiplexes several protocols over one connection | | `TsgcWSPClient_Dataset` / `TsgcWSPServer_Dataset` | Keeps a dataset synchronised across the wire | | `TsgcWSPClient_Files` / `TsgcWSPServer_Files` | File transfer with a quality-of-service level | | `TsgcWSPClient_Presence` / `TsgcWSPServer_Presence` | Channel membership, invitations, member lists | | `TsgcWSPClient_WAMP` / `TsgcWSPServer_WAMP` | WAMP v1: prefixes, topics and RPC | | `TsgcWSPClient_E2EE` / `TsgcWSPServer_E2EE` | End to end encrypted direct and group messages | | `TsgcWSPClient_Lightstreamer` | Client for a Lightstreamer server, no server side | ## Quickstart, the sgc protocol Server: ```pascal uses sgcWebSocket, sgcWebSocket_Protocols, sgcWebSocket_Classes; FServer := TsgcWebSocketServer.Create(Self); FServer.Port := 5000; FProtocol := TsgcWSPServer_sgc.Create(Self); FProtocol.Server := FServer; FServer.Active := True; ``` Client: ```pascal FClient := TsgcWebSocketClient.Create(Self); FClient.Host := 'localhost'; FClient.Port := 5000; FProtocol := TsgcWSPClient_sgc.Create(Self); FProtocol.Client := FClient; FProtocol.OnConnect := ProtocolConnect; FClient.Active := True; ``` Then publish and subscribe by channel: ```pascal procedure TForm1.ProtocolConnect(Connection: TsgcWSConnection); begin FProtocol.Subscribe('prices'); FProtocol.Publish('EURUSD 1.0921', 'prices'); end; ``` On the server, `Broadcast` reaches everyone and takes optional `Exclude` and `Include` lists of connection GUIDs, so you can send to all but the sender: ```pascal FProtocol.Broadcast('server restarting', 'prices'); FProtocol.WriteData(SomeGuid, 'just for you'); ``` ## RPC over the same socket The sgc protocol carries remote calls as well as messages. The client calls, the server answers with a result or an error, both keyed by the id you pass: ```pascal // client FProtocol.RPC('req-1', 'GetQuote', '{"symbol":"EURUSD"}'); // server, inside the RPC event FProtocol.RPCResult('req-1', '{"bid":1.0921}'); // or FProtocol.RPCError('req-1', 500, 'no such symbol'); ``` `Notify` is the same as `RPC` without a reply, for when you do not need one. ## The other protocols in one line each - **Files**: `SendFile(FileName, Size, QoS, Data, FileId)`. The QoS level decides whether delivery is confirmed and retried. - **Dataset**: `Synchronize`, `GetMetaData`, `Subscribe_all`. The server sends changes, the client applies them. - **Presence**: `Subscribe(channel)`, `GetMembers`, `Invite(channel, memberID)`. - **WAMP v1**: `Prefix(prefix, URI)` to shorten topic URIs, then `Subscribe(topicURI)` and `Call(callId, procURI, arguments)`. - **E2EE**: `SendDirectMessage(to, text)` and `SendGroupMessage(group, text)`, with `CreateGroup`, `JoinGroup` and `DeleteGroup` for the group side. - **Lightstreamer**: set `AdapterSet` and `LightstreamerOptions`, then handle `OnLightstreamerUpdate`, `OnLightstreamerSnapshot` and the rest. ## Things that catch people out - A protocol with no transport assigned fails silently. Nothing raises, nothing connects, because the component simply never had a socket. - Client and server must run the same protocol. A `TsgcWSPClient_sgc` against a plain `TsgcWebSocketServer` with no protocol component will connect at the WebSocket level and then do nothing useful. - Subscribe after the protocol connects, not immediately after setting `Active := True` on the transport. - `aGuid` throughout these APIs is the connection identifier, not a message id. It is how you address one specific client from the server. - The WAMP component here is v1. Do not mix it up with WAMP2, which is a separate component in a separate skill. ## Routing - **Find a component**: `reference/components-index.md` lists every component, its `unit`, and its edition, grouped by Reg module. - **Uses clause**: add the component's `unit:` value (shown on its API page) to your `uses` clause. Nothing compiles without it. - **API detail**: `reference/api/.md` has the Properties, Events and Methods, each in both Delphi and C++Builder form. - **Option / enum / event types**: property and event types link to `reference/types/.md`, which documents the sub-properties of option classes, the values of enums, and the parameter list of event handlers. - **Examples**: `examples/index.md` is the full demo catalog; `examples/.md` is a focused, real usage snippet for the most-used components. - **Concepts**: `concepts/overview.md` (getting started + uses-clause rule) and `concepts/editions-and-features.md` (which components your edition includes). - **Bundled resources**: `concepts/resources.md` lists the browser-side assets (JavaScript, HTML, CSS) the server components serve or embed, so a browser client works without an external CDN. - **Version history**: `reference/history.md` lists what changed in each sgcWebSockets release. ## Editions Components are gated by edition (Professional, Enterprise, All-Access) or by a feature define. Check the edition column in the components index, or `concepts/editions-and-features.md`, before relying on a component. Only public and published members are documented. Method bodies, private fields and protected members are intentionally not included.