feat: add a comment to methods listing which message types they use. (#163)

Co-authored-by: Michael Davis <[email protected]>

Author: damaru-inc

filters/all.js

@@ -730,6 +730,7 @@ function getFunctionSpecs(asyncapi, params) {
         functionSpec.sendMethodName = getSendFunctionName(channelName, publish);
         functionSpec.dynamicType = params.dynamicType;
         functionSpec.parametersToHeaders = params.parametersToHeaders;
+        functionSpec.multipleMessageComment = getMultipleMessageComment(publish);
         functionMap.set(name, functionSpec);
       }
       const payload = getPayloadClass(publish);
@@ -766,7 +767,6 @@ function getFunctionSpecs(asyncapi, params) {
             if (!foundIt) {
               debugFunction(`Adding new sub ${sub}`);
               functionSpec.additionalSubscriptions.push(sub);
-
               functionSpec.multipleMessages = true;
             }
           }
@@ -795,13 +795,14 @@ function getFunctionSpecs(asyncapi, params) {
         functionSpec.channelInfo = channelInfo;
         functionSpec.dynamicType = params.dynamicType;
         functionSpec.parametersToHeaders = params.parametersToHeaders;
-        functionMap.set(name, functionSpec);
+        functionSpec.multipleMessageComment = getMultipleMessageComment(subscribe);
         if (smfBinding && smfBinding.queueName && smfBinding.topicSubscriptions) {
           debugFunction(`A new one with subscriptions: ${smfBinding.topicSubscriptions}`);
           functionSpec.additionalSubscriptions = smfBinding.topicSubscriptions;
           functionSpec.isQueueWithSubscription = true;
           functionSpec.multipleMessages = smfBinding.topicSubscriptions && smfBinding.topicSubscriptions.length > 1;
         }
+        functionMap.set(name, functionSpec);
       }
 
       if (functionSpec.multipleMessages) {
@@ -836,6 +837,26 @@ function getFunctionSpecs(asyncapi, params) {
   return functionMap;
 }
 
+function getSendFunctionName(channelName, operation) {
+  return `send${_.upperFirst(getFunctionName(channelName, operation, undefined))}`;
+}
+
+function getMultipleMessageComment(pubOrSub) {
+  let ret;
+
+  // We deliberately leave out the last newline, because that makes it easier to use in the template.
+  // Otherwise it's really hard to get rid of an extra unwanted newline.
+  if (pubOrSub.hasMultipleMessages()) {
+    ret = '// The message can be of type:';
+    pubOrSub.messages().forEach(m => {
+      ret += '\n\t// ';
+      ret += getMessagePayloadType(m);
+    });
+  }
+
+  return ret;
+}
+
 function getPayloadClass(pubOrSub) {
   let ret;
 
@@ -845,32 +866,34 @@ function getPayloadClass(pubOrSub) {
   } else {
     const message = pubOrSub.message();
     if (message) {
-      const payload = message.payload();
-      debugPayload('payload:');
-      debugPayload(payload);
-
-      if (payload) {
-        const type = payload.type();
-        debugPayload('type:');
-        debugPayload(type);
-
-        if (!type || type === 'object') {
-          ret = payload.ext('x-parser-schema-id');
-          ret = _.camelCase(ret);
-          ret = _.upperFirst(ret);
-        } else {
-          ret = getType(type, payload.format()).javaType;
-        }
-      }
+      ret = getMessagePayloadType(message);
     }
   }
   debugPayload(`getPayloadClass: ${ret}`);
 
   return ret;
 }
 
-function getSendFunctionName(channelName, operation) {
-  return `send${_.upperFirst(getFunctionName(channelName, operation, undefined))}`;
+function getMessagePayloadType(message) {
+  let ret;
+  const payload = message.payload();
+  debugPayload('payload:');
+  debugPayload(payload);
+
+  if (payload) {
+    const type = payload.type();
+    debugPayload('type:');
+    debugPayload(type);
+
+    if (!type || type === 'object') {
+      ret = payload.ext('x-parser-schema-id');
+      ret = _.camelCase(ret);
+      ret = _.upperFirst(ret);
+    } else {
+      ret = getType(type, payload.format()).javaType;
+    }
+  }
+  return ret;
 }
 
 // This returns the connection properties for a solace binder, for application.yaml.

template/src/main/java/Application.java

@@ -99,6 +99,9 @@ public static void main(String[] args) {
 	}
 		{%- endif %}
 	{%- elif funcSpec.type === 'consumer' %}
+		{%- if funcSpec.multipleMessageComment %}
+	{{ funcSpec.multipleMessageComment }}
+		{%- endif %}
 	@Bean
 	{{ funcSpec.functionSignature | safe }} {
 		return data -> {
@@ -108,7 +111,7 @@ public static void main(String[] args) {
 	}	
 	{%- else %}{#- it is a supplier. #}
 		{%- if funcSpec.dynamic %}
-			{%- if params.dynamicType === 'header' %}
+			{%- if params.dynamicType === 'header' -%}
 	@Bean
 	{{ funcSpec.functionSignature | safe }} {
 		return () -> {
@@ -130,6 +133,9 @@ public static void main(String[] args) {
 			{# else do nothing, we just use the void function below. #}
 			{%- endif %}{# dynamic type #}
 		{%- else -%}{# it is not dynamic. #}
+			{%- if funcSpec.multipleMessageComment %}
+	{{ funcSpec.multipleMessageComment }}
+			{%- endif %}
 	@Bean
 	{{ funcSpec.functionSignature | safe }} {
 		return () -> {

test/__snapshots__/integration.test.js.snap

@@ -1,5 +1,52 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
+exports[`template integration tests using the generator should generate a comment for a consumer receiving multiple messages 1`] = `
+"
+import java.util.function.Consumer;
+import java.util.function.Supplier;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.context.annotation.Bean;
+import org.springframework.messaging.Message;
+
+@SpringBootApplication
+public class Application {
+
+	private static final Logger logger = LoggerFactory.getLogger(Application.class);
+
+	public static void main(String[] args) {
+		SpringApplication.run(Application.class);
+	}
+
+	// The message can be of type:
+	// Cat
+	// Dog
+	@Bean
+	public Supplier<Message<?>> animalsSupplier() {
+		return () -> {
+			// Add business logic here.
+			return new Message<?>();
+		};
+	}
+
+	// The message can be of type:
+	// Cat
+	// Dog
+	@Bean
+	public Consumer<Message<?>> animalsConsumer() {
+		return data -> {
+			// Add business logic here.	
+			logger.info(data.toString());
+		};
+	}
+
+}
+"
+`;
+
 exports[`template integration tests using the generator should generate application files using the solace binder 1`] = `
 "<?xml version=\\"1.0\\" encoding=\\"UTF-8\\"?>
 <project xmlns=\\"http://maven.apache.org/POM/4.0.0\\" xmlns:xsi=\\"http://www.w3.org/2001/XMLSchema-instance\\" xsi:schemaLocation=\\"http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd\\">

test/integration.test.js

@@ -85,4 +85,19 @@ describe('template integration tests using the generator', () => {
       expect(file).toMatchSnapshot();
     }
   });
-});
+
+  it('should generate a comment for a consumer receiving multiple messages', async () => {
+    const OUTPUT_DIR = generateFolderName();
+    
+    const generator = new Generator(path.normalize('./'), OUTPUT_DIR, { forceWrite: true });
+    await generator.generateFromFile(path.resolve('test', 'mocks/animals.yaml'));
+
+    const expectedFiles = [
+      'src/main/java/Application.java'
+    ];
+    for (const index in expectedFiles) {
+      const file = await readFile(path.join(OUTPUT_DIR, expectedFiles[index]), 'utf8');
+      expect(file).toMatchSnapshot();
+    }
+  });
+});

test/mocks/animals.yaml

@@ -0,0 +1,36 @@
+components:
+  schemas:
+    Dog:
+      type: object
+      properties:
+        name: 
+          type: string
+    Cat:
+      type: object
+      properties:
+        name: 
+          type: string
+  messages:
+    DogMessage:
+      payload:
+        $ref: '#/components/schemas/Dog'
+    CatMessage:
+      payload:
+        $ref: '#/components/schemas/Cat'
+channels:
+  'animals':
+    publish:
+      message:
+        oneOf:
+        - $ref: '#/components/messages/CatMessage'
+        - $ref: '#/components/messages/DogMessage'
+    subscribe:
+      message:
+        oneOf:
+        - $ref: '#/components/messages/CatMessage'
+        - $ref: '#/components/messages/DogMessage'
+asyncapi: 2.0.0
+info:
+  description: Testing oneOf
+  title: animals
+  version: 0.0.1