feat: generate schema from example message (#191)

Author: dalelane

components/Common.js

@@ -15,7 +15,7 @@
 */
 
 import { createJavaArgsFromProperties } from '../utils/Types.utils';
-import { collateModelNames } from '../utils/Models.utils';
+import { collateModelNames, getMessagePayload } from '../utils/Models.utils';
 import { MQCipherToJava } from './Connection/MQTLS';
 
 export function Class({ childrenContent, name, implementsClass, extendsClass }) {
@@ -180,7 +180,7 @@ import ${params.package}.models.${messageName};`;
 /* Used to resolve a channel object to message name */
 export function ChannelToMessage(channel, asyncapi) {
   const message = channel.messages().all()[0];
-  const targetPayloadProperties = message.payload().properties();
+  const targetPayloadProperties = getMessagePayload(message).properties();
   const targetMessageName = message.name();
 
   const messageNameTitleCase = targetMessageName.charAt(0).toUpperCase() + targetMessageName.slice(1);

components/Demo/Demo.js

@@ -19,6 +19,7 @@ import { DemoProducer } from './DemoProducer';
 import { javaPackageToPath, toJavaClassName } from '../../utils/String.utils';
 import { File } from '@asyncapi/generator-react-sdk';
 import { createJavaConstructorArgs } from '../../utils/Types.utils';
+import { getMessagePayload } from '../../utils/Models.utils';
 import { PackageDeclaration } from '../Common';
 
 export function Demo(asyncapi, params) {
@@ -39,7 +40,7 @@ export function Demo(asyncapi, params) {
   // Get payload from either publish or subscribe
   const message = channel.messages().all()[0];
   const targetMessageName = message.id() || message.name();
-  const targetPayloadProperties = message.payload().properties();
+  const targetPayloadProperties = getMessagePayload(message).properties();
 
   const messageNameTitleCase = toJavaClassName(targetMessageName);
 

components/Files/Models.js

@@ -19,7 +19,7 @@ import { PackageDeclaration, ImportDeclaration, Class, ClassConstructor } from '
 import { ModelClassVariables, ModelConstructor } from '../Model';
 import { javaPackageToPath } from '../../utils/String.utils';
 import { Indent, IndentationTypes } from '@asyncapi/generator-react-sdk';
-import { collateModels } from '../../utils/Models.utils';
+import { collateModels, getMessagePayload } from '../../utils/Models.utils';
 
 export function Models(asyncapi, params) {
   const models = collateModels(asyncapi);
@@ -40,7 +40,7 @@ export function Models(asyncapi, params) {
             <ModelClassVariables message={message}></ModelClassVariables>
           </Indent>
 
-          <ClassConstructor name={messageNameUpperCase} properties={message.payload().properties()}>
+          <ClassConstructor name={messageNameUpperCase} properties={getMessagePayload(message).properties()}>
             <ModelConstructor message={message}/>
           </ClassConstructor>
           <ClassConstructor name={messageNameUpperCase}>

components/Model.js

@@ -15,15 +15,16 @@
 */
 
 import { setLocalVariables, defineVariablesForProperties } from '../utils/Types.utils';
+import { getMessagePayload } from '../utils/Models.utils';
 
 export function ModelConstructor({ message }) {
   // TODO: Supoort ofMany messages
-  return (setLocalVariables(message.payload().properties()).join(''));
+  return (setLocalVariables(getMessagePayload(message).properties()).join(''));
 }
 
 export function ModelClassVariables({ message }) {
   // TODO: Supoort ofMany messages
-  const argsString = defineVariablesForProperties(message.payload());
+  const argsString = defineVariablesForProperties(getMessagePayload(message));
 
   return argsString.join(`
 `);

package-lock.json

@@ -33,7 +33,8 @@
   "dependencies": {
     "@asyncapi/generator-filters": "^2.1.0",
     "@asyncapi/generator-hooks": "^0.1.0",
-    "@asyncapi/generator-react-sdk": "^1.0.11"
+    "@asyncapi/generator-react-sdk": "^1.0.11",
+    "generate-schema": "^2.6.0"
   },
   "release": {
     "branches": [

package.json

@@ -33,6 +33,7 @@ describe('kafka integration tests using the generator', () => {
       `${PACKAGE_PATH}/ConnectionHelper.java`,
       `${PACKAGE_PATH}/LoggingHelper.java`,
       `${PACKAGE_PATH}/PubSubBase.java`,
+      `${PACKAGE_PATH}/models/ModelContract.java`,
     ];
     for (const file of commonFiles) {
       expect(existsSync(path.join(OUTPUT_DIR, file))).toBe(true);
@@ -64,7 +65,6 @@ describe('kafka integration tests using the generator', () => {
         'DemoSubscriber.java',
         'SongReleasedProducer.java',
         'SongReleasedSubscriber.java',
-        'models/ModelContract.java',
         'models/Song.java',
       ],
       [
@@ -84,7 +84,6 @@ describe('kafka integration tests using the generator', () => {
       [
         'DemoProducer.java',
         'SongReleasedProducer.java',
-        'models/ModelContract.java',
         'models/Song.java',
       ],
       [
@@ -105,7 +104,6 @@ describe('kafka integration tests using the generator', () => {
         'DemoSubscriber.java',
         'SongReleasedProducer.java',
         'SongReleasedSubscriber.java',
-        'models/ModelContract.java',
         'models/Song.java',
       ],
       [
@@ -124,7 +122,6 @@ describe('kafka integration tests using the generator', () => {
       [
         'DemoSubscriber.java',
         'SongReleasedSubscriber.java',
-        'models/ModelContract.java',
         'models/Song.java',
       ],
       [
@@ -149,7 +146,6 @@ describe('kafka integration tests using the generator', () => {
         'SmartylightingStreetlights10EventStreetlightIdLightingMeasuredSubscriber.java',
         'models/DimLight.java',
         'models/LightMeasured.java',
-        'models/ModelContract.java',
         'models/TurnOnOff.java',
       ],
       [
@@ -173,7 +169,6 @@ describe('kafka integration tests using the generator', () => {
         'LightTurnOnProducer.java',
         'models/DimLight.java',
         'models/LightMeasured.java',
-        'models/ModelContract.java',
         'models/TurnOn.java',
       ],
       [
@@ -182,4 +177,23 @@ describe('kafka integration tests using the generator', () => {
       ]);
     expect(verified).toBe(true);
   });
+
+  it('should generate code for an AsyncAPI doc without payload schema', async () => {
+    const verified = await generateJavaProject(
+      'com.eem',
+      {
+        server: 'gateway-group',
+      },
+      'mocks/kafka-orders-v3.yml',
+      [
+        'DemoSubscriber.java',
+        'ORDERSJSONSubscriber.java',
+        'models/Message.java',
+      ],
+      [
+        'props.put("security.protocol", "SASL_SSL")',
+        'props.put("sasl.mechanism", "PLAIN")',
+      ]);
+    expect(verified).toBe(true);
+  });
 });

test/Kafka.test.js

@@ -0,0 +1,34 @@
+asyncapi: 3.0.0
+info:
+  title: ORDERS.JSON
+  version: 1.0.0
+  contact:
+    email: username@example.com
+channels:
+  ORDERS.JSON:
+    address: ORDERS.JSON
+    bindings:
+      kafka:
+        partitions: 3
+        replicas: 3
+    messages:
+      message:
+        examples:
+          - payload: {"id":"973fb57a-4fcc-42df-8710-440c7c3ec32c","customer":"Dionne Howell","customerid":"26b87be0-2be7-4e2d-b5de-43d83d51ee49","description":"M Acid-washed Capri Jeans","price":47.85,"quantity":7,"region":"EMEA","ordertime":"2024-03-09 15:37:19.769"}
+operations:
+  receiveMessage:
+    action: receive
+    channel:
+      $ref: '#/channels/ORDERS.JSON'
+    messages:
+      - $ref: '#/channels/ORDERS.JSON/messages/message'
+servers:
+  gateway-group:
+    host: my-kafka-hostname:9092
+    protocol: kafka-secure
+    security:
+      - $ref: '#/components/securitySchemes/EGW-SECURITY'
+components:
+  securitySchemes:
+    EGW-SECURITY:
+      type: plain

test/mocks/kafka-orders-v3.yml

@@ -1,4 +1,5 @@
 import { toJavaClassName } from './String.utils';
+import { json } from 'generate-schema';
 
 export function collateModelNames(asyncapi) {
   return Object.keys(collateModels(asyncapi));
@@ -13,4 +14,44 @@ export function collateModels(asyncapi) {
   }
 
   return models;
+}
+
+
+// The rest of the generator depends on a message object
+//  having a payload with properties. This is needed to
+//  be able to generate Java classes with attributes
+//  matching the expected properties.
+//
+// Some AsyncAPI documents don't include payload properties
+//  but provide a sample message instead. For these
+//  documents, we can attempt to derive a schema from
+//  the sample, and use that schema to generate a usable
+//  set of properties.
+export function getMessagePayload(message) {
+  let payload = message.payload();
+  if (!payload) {
+    payload = {
+      required: () => { return false; }
+    };
+  }
+  if (!payload.properties || !payload.properties()) {
+    const generatedProperties = {};
+
+    const examples = message.examples().all();
+    if (examples && examples.length > 0) {
+      const example = examples[0];
+      const examplePayload = example.payload();
+      const jsonSchema = json('schema', examplePayload).properties;
+      Object.keys(jsonSchema).forEach((propertyName) => {
+        generatedProperties[propertyName] = {
+          type: () => { return jsonSchema[propertyName].type; },
+          format: () => { return; },
+          required: () => { return false; }
+        };
+      });
+    }
+
+    payload.properties = () => { return generatedProperties; };
+  }
+  return payload;
 }