Files
agentic-dev/packages/core-realtime/src/socket-io-realtime-server.ts

126 lines
4.6 KiB
TypeScript

import type { Server as IOServer, Socket, DefaultEventsMap } from "socket.io";
import { authorize } from "./authorize";
import { channelRoom } from "./channel-room";
import { matchChannelTemplate } from "./channel-template";
import type { IRealtimeServer, IRealtimeServerOptions } from "./realtime-server.interface";
/** Shape of per-socket session data attached by Gate 1. */
type AppSocketData = { user: { userId: string; roles: string[] } | null };
/** Fully-typed Socket alias so `socket.data.user` resolves to `AppSocketData["user"]`. */
type AppSocket = Socket<DefaultEventsMap, DefaultEventsMap, DefaultEventsMap, AppSocketData>;
function parseCookies(header: string): Record<string, string> {
const out: Record<string, string> = {};
for (const part of header.split(";")) {
const [k, ...rest] = part.trim().split("=");
if (k) out[k] = decodeURIComponent(rest.join("="));
}
return out;
}
export class SocketIORealtimeServer implements IRealtimeServer {
private readonly io: IOServer;
private readonly opts: IRealtimeServerOptions;
constructor(opts: IRealtimeServerOptions) {
this.opts = opts;
this.io = opts.io;
}
async start(): Promise<void> {
const { authenticator, registry } = this.opts;
// Gate 1: connect — read cookie, authenticate, attach user.
// If the authenticator throws (e.g. malformed token), the connection is
// rejected so the client receives `connect_error`.
(this.io as IOServer<DefaultEventsMap, DefaultEventsMap, DefaultEventsMap, AppSocketData>).use(
async (socket, next) => {
try {
const cookies = parseCookies(socket.handshake.headers.cookie ?? "");
socket.data.user = await authenticator.authenticate({
cookies,
headers: socket.handshake.headers as Record<string, string>,
});
next();
} catch (err) {
next(err instanceof Error ? err : new Error(String(err)));
}
},
);
this.io.on("connection", (rawSocket) => {
const socket = rawSocket as AppSocket;
// Gate 2: subscribe.
socket.on("subscribe", async (requestedName: string, ack?: (r: unknown) => void) => {
// Find a registered descriptor whose name (or template) matches requestedName.
// listChannels() covers both inbound descriptors and outbound-only channels.
let matched: { descriptor: { name: string; scope: unknown }; params: Record<string, string> } | null = null;
for (const descriptor of registry.listChannels()) {
const m = matchChannelTemplate(descriptor.name, requestedName);
if (m) {
matched = { descriptor, params: m.params };
break;
}
}
if (!matched) {
ack?.({ ok: false, error: "unknown_channel" });
return;
}
const allowed = await authorize(
matched.descriptor as never,
matched.params,
socket.data.user ?? null,
);
if (!allowed) {
ack?.({ ok: false, error: "forbidden" });
return;
}
socket.join(channelRoom(requestedName));
ack?.({ ok: true });
});
// Gate 3: inbound — one listener per registered channel.
for (const entry of registry.list()) {
socket.on(entry.descriptor.name, async (payload: unknown, ack?: (r: unknown) => void) => {
const parsed = entry.descriptor.schema.safeParse(payload);
if (!parsed.success) {
ack?.({ ok: false, error: "invalid_input" });
return;
}
// For userScoped channels, derive params from the authenticated user
// so the owner's own socket passes the `params.userId === user.userId` check.
const scope = entry.descriptor.scope;
const params: Record<string, string> =
typeof scope === "object" && "userScoped" in scope
? { userId: socket.data.user?.userId ?? "" }
: {};
const allowed = await authorize(entry.descriptor, params, socket.data.user ?? null);
if (!allowed) {
ack?.({ ok: false, error: "forbidden" });
return;
}
try {
await entry.handler(parsed.data, {
userId: socket.data.user?.userId ?? null,
roles: socket.data.user?.roles ?? [],
});
ack?.({ ok: true });
} catch {
ack?.({ ok: false, error: "handler_error" });
}
});
}
});
}
async stop(): Promise<void> {
await new Promise<void>((resolve) => this.io.close(() => resolve()));
}
}