src/broker-amqp.ts

@@ -81,6 +81,10 @@ export async function connectAmqp(
   opts: { assumeExchanges?: boolean } = {},
 ): Promise<Broker> {
   const cred: Credential = typeof target === "string" ? { url: target } : target;
+  // This module's own name, for turning a local event name into this bus's routing key. From the
+  // credential where the mesh issued one, and from the environment for an ad-hoc client that has no
+  // credential of its own — the same two places subscribe already looks.
+  const self = cred.module ?? process.env.MESH_MODULE ?? "";
   const conn = cred.fingerprint
     ? await amqp.connect(cred.url, await pinnedOptions(cred.url, cred.fingerprint))
     : await amqp.connect(cred.url);
@@ -140,7 +144,7 @@ export async function connectAmqp(
   let eventConsumerTag: string | undefined;
 
   async function dispatchEvent(msg: amqp.ConsumeMessage): Promise<void> {
-    const key = msg.fields.routingKey;
+    const key = localKeyFor(msg.fields.routingKey);
     let env: Envelope<unknown>;
     try {
       env = toEnvelope(msg);
@@ -220,7 +224,7 @@ export async function connectAmqp(
       await new Promise<void>((resolve, reject) => {
         ch.publish(
           EVENTS_EXCHANGE,
-          env.key,
+          routingKeyFor(env.key, self),
           Buffer.from(JSON.stringify(env.body)),
           {
             persistent: true,
@@ -253,7 +257,7 @@ export async function connectAmqp(
           }
           eventQueue = name;
         }
-        await ch.bindQueue(eventQueue, EVENTS_EXCHANGE, pattern);
+        await ch.bindQueue(eventQueue, EVENTS_EXCHANGE, bindingFor(pattern));
         const sub: EventSub = { pattern, handler: handler as EventSub["handler"] };
         eventSubs.push(sub);
         if (!eventConsumerTag) {
@@ -269,7 +273,7 @@ export async function connectAmqp(
       }
 
       const { queue } = await ch.assertQueue("", { exclusive: true });
-      await ch.bindQueue(queue, EVENTS_EXCHANGE, pattern);
+      await ch.bindQueue(queue, EVENTS_EXCHANGE, bindingFor(pattern));
       const consumer = await ch.consume(queue, (msg) => {
         if (!msg) return;
         void (async () => {
@@ -376,7 +380,9 @@ function topicMatches(pattern: string, key: string): boolean {
 function matchFrom(p: string[], pi: number, k: string[], ki: number): boolean {
   while (pi < p.length) {
     const tok = p[pi];
-    if (tok === "#") {
+    // `**` is the mesh's wildcard for the rest of a name; `#` is this bus's, accepted so a pattern
+    // written either way behaves the same while both buses ship (novox/hq design 29 §1).
+    if (tok === "#" || tok === "**") {
       if (pi === p.length - 1) return true; // trailing # swallows the rest, including nothing
       for (let skip = ki; skip <= k.length; skip++) {
         if (matchFrom(p, pi + 1, k, skip)) return true;
@@ -390,3 +396,27 @@ function matchFrom(p: string[], pi: number, k: string[], ki: number): boolean {
   }
   return ki === k.length;
 }
+
+/** This bus spells an event as a routing key that repeats the emitter's name: `module.<emitter>.<event>`.
+ *  A module names its events locally and the mesh derives where they land (novox/hq design 29 §1), so
+ *  the mapping lives here rather than in every module.
+ *
+ *  **Why it exists at all.** Until 04-ISSUES/127 every module passed the routing key itself, which
+ *  worked on this bus and derived into a namespace nobody owns on the one being built. Converting the
+ *  modules to local names without this would have broken the mesh that is actually running. */
+function routingKeyFor(key: string, self: string): string {
+  return key.startsWith("module.") ? key : `module.${self}.${key}`;
+}
+
+/** A local pattern as this bus's binding. `**` is the mesh's wildcard for the rest of a name; here
+ *  that is `#`, and on the bus being built it is `>`. Neither spelling appears in a manifest. */
+function bindingFor(pattern: string): string {
+  const here = pattern.split(".").map((part) => (part === "**" ? "#" : part)).join(".");
+  if (here === "#") return "#";
+  return here.startsWith("module.") ? here : `module.${here}`;
+}
+
+/** A routing key as the local name a handler and a manifest both use: the emitter and the event. */
+function localKeyFor(routingKey: string): string {
+  return routingKey.startsWith("module.") ? routingKey.slice("module.".length) : routingKey;
+}

src/broker-nats.ts

@@ -255,11 +255,23 @@ function toEnvelope<T>(msg: JsMsg): Envelope<T> {
   };
 }
 
-/** The event key inside a module's event subject. */
+/** The event key a module sees: the emitter and the event, which is exactly how its manifest names
+ *  what it consumes (novox/hq design 29 §1, 04-ISSUES/127).
+ *
+ *  **One vocabulary for the declaration and the handler.** This returned the event name alone, so a
+ *  manifest declaring `consumes: builder.built` produced a handler pattern that could never match
+ *  the key it was compared against — and a module consuming the same event from two emitters could
+ *  not tell them apart except by reading a header. The subject already carries the emitter; naming it
+ *  here makes a mismatch between manifest and code a typo rather than a category error. */
 function keyFromSubject(subject: string): string {
   const marker = ".event.";
   const at = subject.indexOf(marker);
-  return at < 0 ? subject : subject.slice(at + marker.length);
+  if (at < 0) return subject;
+  const event = subject.slice(at + marker.length);
+  // `mesh.mod.<emitter>.event.…` — the emitter is the token before the marker.
+  const before = subject.slice(0, at).split(".");
+  const emitter = before[before.length - 1];
+  return emitter ? `${emitter}.${event}` : event;
 }
 
 /** A module's own event subject. Derived, never taken from the caller: the module names its
@@ -325,7 +337,9 @@ export function topicMatches(pattern: string, key: string): boolean {
 
 function matchFrom(p: string[], pi: number, k: string[], ki: number): boolean {
   if (pi === p.length) return ki === k.length;
-  if (p[pi] === "#") {
+  // `**` is the mesh's wildcard for the rest of a name; `#` is the old bus's, accepted so a pattern
+  // written either way behaves the same while both buses ship (novox/hq design 29 §1).
+  if (p[pi] === "#" || p[pi] === "**") {
     for (let skip = ki; skip <= k.length; skip++) {
       if (matchFrom(p, pi + 1, k, skip)) return true;
     }