mesh-tools — the tool runtime and AMQP broker binding

The per-node process that makes a module's tools serve on the mesh:
- broker-amqp.ts: a concrete AMQP implementation of the sdk's Broker
  contract (request/reply over a reply queue + correlation id, publish/
  subscribe over a topic exchange). Kept here, not in the sdk, so a
  broker-client change never rebuilds a module (ADR 0044).
- runtime.ts: bind the broker, import the assigned modules' tool
  entrypoints (each registers as it loads), serveTools. The thin wrapper.
- main.ts: the entrypoint, configured by MESH_BROKER_URL + MESH_TOOL_MODULES.
- Dockerfile: the container a node runs it as.

Verified over a REAL broker: the test spins LavinMQ (the mesh's broker),
the runtime serves a registered tool, a separate connection invokes it by
name over AMQP and gets the result, and an unknown tool is refused over
the wire. So 'modules can serve' is now running-on-the-mesh, not just
proven in a mock.

Claude-Session: https://claude.ai/code/session_01LrgweAeERJYBg88c5cKDzF
This commit is contained in:
2026-09-03 23:21:01 +02:00
commit 9eddcdb0a0
10 changed files with 421 additions and 0 deletions
+103
View File
@@ -0,0 +1,103 @@
// A concrete AMQP implementation of the sdk's Broker contract, over the mesh broker
// (novox/hq ADR 0001). The sdk deliberately keeps this out — it defines the interface; the runtime
// provides the binding — so a broker-client change never rebuilds the modules.
import amqp from "amqplib";
import { randomUUID } from "node:crypto";
import type { Broker, Envelope } from "@novox/mesh-sdk/messaging";
const EXCHANGE = "mesh.tools"; // one topic exchange carries tool invocations and events
interface Reply {
result?: unknown;
error?: string;
}
/** Connect to the mesh broker and return a Broker. `close()` tears both channel and connection down. */
export async function connectAmqp(url: string): Promise<Broker> {
const conn = await amqp.connect(url);
const ch = await conn.createChannel();
await ch.assertExchange(EXCHANGE, "topic", { durable: true });
// Request/reply: one exclusive reply queue, correlationId → resolver.
const { queue: replyQueue } = await ch.assertQueue("", { exclusive: true });
const pending = new Map<string, (r: Reply) => void>();
await ch.consume(
replyQueue,
(msg) => {
if (!msg) return;
const resolve = pending.get(msg.properties.correlationId);
if (resolve) {
pending.delete(msg.properties.correlationId);
resolve(JSON.parse(msg.content.toString()) as Reply);
}
},
{ noAck: true },
);
return {
async request<Req, Res>(key: string, body: Req): Promise<Res> {
const id = randomUUID();
const answered = new Promise<Res>((resolve, reject) => {
const timer = setTimeout(() => {
if (pending.delete(id)) reject(new Error(`request ${key} timed out`));
}, 30_000);
pending.set(id, (r) => {
clearTimeout(timer);
if (r.error) reject(new Error(r.error));
else resolve(r.result as Res);
});
});
ch.publish(EXCHANGE, key, Buffer.from(JSON.stringify(body)), {
correlationId: id,
replyTo: replyQueue,
});
return answered;
},
async handle<Req, Res>(key: string, handler: (body: Req) => Promise<Res>): Promise<() => void> {
const { queue } = await ch.assertQueue(`serve.${key}`, { durable: true });
await ch.bindQueue(queue, EXCHANGE, key);
const consumer = await ch.consume(queue, (msg) => {
if (!msg) return;
void (async () => {
let reply: Reply;
try {
reply = { result: await handler(JSON.parse(msg.content.toString()) as Req) };
} catch (err) {
reply = { error: err instanceof Error ? err.message : String(err) };
}
if (msg.properties.replyTo) {
ch.sendToQueue(msg.properties.replyTo, Buffer.from(JSON.stringify(reply)), {
correlationId: msg.properties.correlationId,
});
}
ch.ack(msg);
})();
});
return () => void ch.cancel(consumer.consumerTag);
},
async publish<T>(env: Envelope<T>): Promise<void> {
ch.publish(EXCHANGE, env.key, Buffer.from(JSON.stringify(env.body)));
},
async subscribe<T>(pattern: string, handler: (env: Envelope<T>) => Promise<void>): Promise<() => void> {
const { queue } = await ch.assertQueue("", { exclusive: true });
await ch.bindQueue(queue, EXCHANGE, pattern);
const consumer = await ch.consume(queue, (msg) => {
if (!msg) return;
void (async () => {
await handler({ key: msg.fields.routingKey, node: "", body: JSON.parse(msg.content.toString()) as T });
ch.ack(msg);
})();
});
return () => void ch.cancel(consumer.consumerTag);
},
async close(): Promise<void> {
await ch.close();
await conn.close();
},
};
}
+38
View File
@@ -0,0 +1,38 @@
// The runnable entrypoint. Reads its configuration from the environment the host resolved for it,
// connects the mesh broker, and serves the assigned modules' tools until stopped.
//
// MESH_BROKER_URL amqp://… the mesh broker
// MESH_TOOL_MODULES /path/a,/path/b,… compiled tool entrypoints of the assigned modules
import { connectAmqp } from "./broker-amqp.js";
import { runTools } from "./runtime.js";
async function main(): Promise<void> {
const url = requireEnv("MESH_BROKER_URL");
const moduleEntrypoints = (process.env.MESH_TOOL_MODULES ?? "")
.split(",")
.map((s) => s.trim())
.filter(Boolean);
const broker = await connectAmqp(url);
const stop = await runTools({ broker, moduleEntrypoints });
const shutdown = async (): Promise<void> => {
stop();
await broker.close();
process.exit(0);
};
process.on("SIGTERM", () => void shutdown());
process.on("SIGINT", () => void shutdown());
}
function requireEnv(name: string): string {
const v = process.env[name];
if (!v) {
console.error(`mesh-tools: ${name} is not set — the runtime cannot serve without it`);
process.exit(1);
}
return v;
}
void main();
+32
View File
@@ -0,0 +1,32 @@
// The tool runtime — the thin per-node process that makes a module's tools actually serve. It
// binds the mesh broker, loads the assigned modules' tool entrypoints (each of which calls
// registerModuleTools as it imports), and hands them to the sdk's serving harness. Everything hard
// — dispatch, collection, duplicate-name safety — is the sdk's; this is the wrapper.
import { pathToFileURL } from "node:url";
import { resolve } from "node:path";
import { useBroker } from "@novox/mesh-sdk/messaging";
import { serveTools, listTools } from "@novox/mesh-sdk/tools";
import type { Broker } from "@novox/mesh-sdk/messaging";
export interface RuntimeOptions {
/** The mesh broker to serve over. */
broker: Broker;
/** Absolute paths to the assigned modules' compiled tool entrypoints (e.g. .../umami/tools/index.js). */
moduleEntrypoints: string[];
}
/** Load the modules, bind the broker, and serve. Returns a stop function that unhooks serving. */
export async function runTools(opts: RuntimeOptions): Promise<() => void> {
useBroker(() => opts.broker);
for (const entry of opts.moduleEntrypoints) {
// Importing the entrypoint runs its registerModuleTools(...) — that is the whole handshake.
await import(pathToFileURL(resolve(entry)).href);
}
const stop = await serveTools(opts.broker);
const tools = listTools();
console.log(`[mesh-tools] serving ${tools.length} tool(s): ${tools.map((t) => t.name).join(", ") || "(none)"}`);
return stop;
}