fix(microservices): no messages emitted with mqtt when qos set #14079

packages/microservices/client/client-mqtt.ts

@@ -210,15 +210,22 @@ export class ClientMqtt extends ClientProxy {
       return undefined;
     }
 
-    return {
-      ...requestOptions,
-      properties: {
-        ...requestOptions?.properties,
+    // Cant just spread objects as MQTT won't deliver
+    // any message with empty object as "userProperties" field
+    // @url https://github.com/nestjs/nest/issues/14079
+    let options: MqttRecordOptions = {};
+    if (requestOptions) {
+      options = { ...requestOptions };
+    }
+    if (this.options?.userProperties) {
+      options.properties = {
+        ...options.properties,
         userProperties: {
           ...this.options?.userProperties,
-          ...requestOptions?.properties?.userProperties,
+          ...options.properties?.userProperties,
         },
-      },
-    };
+      };
+    }
+    return options;
   }
 }

packages/microservices/listener-metadata-explorer.ts

@@ -39,36 +39,25 @@ export class ListenerMetadataExplorer {
     const instancePrototype = Object.getPrototypeOf(instance);
     return this.metadataScanner
       .getAllMethodNames(instancePrototype)
-      .map(method =>
-        this.exploreMethodMetadata(instance, instancePrototype, method),
-      )
+      .map(method => this.exploreMethodMetadata(instancePrototype, method))
       .filter(metadata => metadata);
   }
 
   public exploreMethodMetadata(
-    instance: Controller,
     instancePrototype: object,
     methodKey: string,
   ): EventOrMessageListenerDefinition {
-    const prototypeCallback = instancePrototype[methodKey];
+    const targetCallback = instancePrototype[methodKey];
     const handlerType = Reflect.getMetadata(
       PATTERN_HANDLER_METADATA,
-      prototypeCallback,
+      targetCallback,
     );
     if (isUndefined(handlerType)) {
       return;
     }
-    const patterns = Reflect.getMetadata(PATTERN_METADATA, prototypeCallback);
-    const transport = Reflect.getMetadata(
-      TRANSPORT_METADATA,
-      prototypeCallback,
-    );
-    const extras = Reflect.getMetadata(
-      PATTERN_EXTRAS_METADATA,
-      prototypeCallback,
-    );
-
-    const targetCallback = instance[methodKey];
+    const patterns = Reflect.getMetadata(PATTERN_METADATA, targetCallback);
+    const transport = Reflect.getMetadata(TRANSPORT_METADATA, targetCallback);
+    const extras = Reflect.getMetadata(PATTERN_EXTRAS_METADATA, targetCallback);
     return {
       methodKey,
       targetCallback,

packages/microservices/test/listeners-metadata-explorer.spec.ts

@@ -71,7 +71,6 @@ describe('ListenerMetadataExplorer', () => {
     });
     it(`should return undefined when "handlerType" metadata is undefined`, () => {
       const metadata = instance.exploreMethodMetadata(
-        test,
         Object.getPrototypeOf(test),
         'noPattern',
       );
@@ -81,7 +80,6 @@ describe('ListenerMetadataExplorer', () => {
     describe('@MessagePattern', () => {
       it(`should return pattern properties when "handlerType" metadata is not undefined`, () => {
         const metadata = instance.exploreMethodMetadata(
-          test,
           Object.getPrototypeOf(test),
           'testMessage',
         );
@@ -98,7 +96,6 @@ describe('ListenerMetadataExplorer', () => {
       });
       it(`should return multiple patterns when more than one is declared`, () => {
         const metadata = instance.exploreMethodMetadata(
-          test,
           Object.getPrototypeOf(test),
           'testMultipleMessage',
         );
@@ -119,7 +116,6 @@ describe('ListenerMetadataExplorer', () => {
     describe('@EventPattern', () => {
       it(`should return pattern properties when "handlerType" metadata is not undefined`, () => {
         const metadata = instance.exploreMethodMetadata(
-          test,
           Object.getPrototypeOf(test),
           'testEvent',
         );
@@ -136,7 +132,6 @@ describe('ListenerMetadataExplorer', () => {
       });
       it(`should return multiple patterns when more than one is declared`, () => {
         const metadata = instance.exploreMethodMetadata(
-          test,
           Object.getPrototypeOf(test),
           'testMultipleEvent',
         );