chore: add Integrate with maven example (#1579)

docs/integration.md

@@ -54,3 +54,20 @@ To be on the safeside, only enable the user to chose between the internal option
 
 ## Integrate Modelina in an AsyncAPI generator template
 TODO
+
+## Integrate Modelina into Maven
+
+There are at least two ways you can integrate Modelina into your build process for Maven projects, either with the AsyncAPI CLI or with a custom build script. Which one to choose all depends on your scenario, look below:
+
+**Custom build script**
+- DO work with other inputs then AsyncAPI
+- DO work when needing extensive build options and configurations
+
+Checkout the Maven example here: [Integrate Modelina into Maven](../examples/integrate-modelina-into-maven/maven-project/)
+
+**AsyncAPI CLI**
+
+- DO NOT work if you have other inputs then AsyncAPI
+- DO NOT need extensive build options and configuration
+
+We don't have a full example for this, but you can use similar concept as the custom build script. However, instead you just install and call the AsyncAPI CLI directly in the plugin execution when utilizing the [frontend-maven-plugin](https://github.com/eirslett/frontend-maven-plugin) and [more specifically the NPX execution](https://github.com/eirslett/frontend-maven-plugin#npx).

docs/languages/Java.md

@@ -92,3 +92,6 @@ Currently not supported, [let everyone know you need it](https://github.com/asyn
 
 ### To and from binary
 Currently not supported, [let everyone know you need it](https://github.com/asyncapi/modelina/issues/new?assignees=&labels=enhancement&template=enhancement.md)!
+
+## Integrate Modelina into Maven
+We have created an example Maven project to show you how to generate AsyncAPI payload models from your AsyncAPI file and integrate it into the build process. [You can find the integration example here](../integration.md#integrate-modelina-into-maven).

examples/README.md

@@ -68,8 +68,9 @@ These are all the basic generator examples that shows a bare minimal example of
 
 ## Integrations
 These are examples of how you can integrate Modelina into a specific scenario:
-- [integrate with React](./integrate-with-react) - A basic example that shows how you can integrate Modelina with React.
+- [integrate-with-react](./integrate-with-react) - A basic example that shows how you can integrate Modelina with React.
 - [integrate-with-next](./integrate-with-next) - A basic example that shows how you can integrate Modelina with Next.
+- [integrate-modelina-into-maven](./integrate-modelina-into-maven) - A basic example that shows how you can integrate Modelina into the Java Maven build process.
 
 ## Python
 These are all specific examples only relevant to the Python generator:
@@ -94,6 +95,7 @@ These are all specific examples only relevant to the Java generator:
 - [java-generate-equals](./java-generate-equals) - A basic example that shows how to generate models that overwrite the `equal` method
 - [java-generate-javax-constraint-annotation](./java-generate-javax-constraint-annotation) - A basic example that shows how Java data models having `javax.validation.constraints` annotations can be generated.
 - [java-generate-javadoc](./java-generate-javadoc) - A basic example of how to generate Java models including JavaDocs.
+- [integrate-modelina-into-maven](./integrate-modelina-into-maven/) - A basic example that shows how you can integrate Modelina into the Java Maven build process.
 
 ## C#
 These are all specific examples only relevant to the C# generator:

examples/integrate-modelina-into-maven/README.md

@@ -0,0 +1,3 @@
+# Integrate Modelina into Maven 
+
+This example show how you can integrate Modelina into Maven with a custom build script. [Please have a look at the Maven project README file for further information](./maven-project/README.md).

examples/integrate-modelina-into-maven/maven-project/.gitignore

@@ -0,0 +1,25 @@
+
+target/
+pom.xml.tag
+pom.xml.releaseBackup
+pom.xml.versionsBackup
+pom.xml.next
+release.properties
+dependency-reduced-pom.xml
+buildNumber.properties
+.mvn/timing.properties
+# https://github.com/takari/maven-wrapper#usage-without-binary-jar
+.mvn/wrapper/maven-wrapper.jar
+
+# Eclipse m2e generated files
+# Eclipse Core
+.project
+# JDT-specific (Eclipse Java Development Tools)
+.classpath
+
+bin
+.settings
+
+# Ignore Modelina generation node modules 
+scripts/modelina/java_runtime_node
+scripts/modelina/node_modules

examples/integrate-modelina-into-maven/maven-project/README.md

@@ -0,0 +1,10 @@
+# Integrate Modelina into Maven
+
+This Java Maven project shows an example how to integrate Modelina and AsyncAPI into your build process. 
+
+Here is how it works:
+- The script `./scripts/modelina/generate.ts` is what generates all the models, and what Maven uses to generate the models. This can also be executed manually through `npm run generate`.
+- The input, in this case, is an AsyncAPI document located in the root of the project `./asyncapi.json`. The input can be anything, just alter the generator script.
+- The Maven project file `./pom.xml` then utilizes the [frontend-maven-plugin](https://github.com/eirslett/frontend-maven-plugin) to execute the generate script on build so you will always have the up to date models from your AsyncAPI document.
+
+> NOTICE: The only thing you manually have to change for this to work in your project is the dependency entry for `"@asyncapi/modelina": "file:../../../../../",` in the `./scripts/modelina/package.json` file to use the latest Modelina version (we only use a local one for testing purposes).

examples/integrate-modelina-into-maven/maven-project/asyncapi.json

@@ -0,0 +1,26 @@
+{
+  "asyncapi": "2.2.0",
+  "info": {
+    "title": "example",
+    "version": "0.1.0"
+  },
+  "channels": {
+    "/test": {
+      "subscribe": {
+        "message": {
+          "payload": {
+            "$schema": "http://json-schema.org/draft-07/schema#",
+            "type": "object",
+            "additionalProperties": false,
+            "properties": {
+              "email": {
+                "type": "string",
+                "format": "email"
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

examples/integrate-modelina-into-maven/maven-project/pom.xml

@@ -0,0 +1,113 @@
+<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+
+  <groupId>com.mycompany.app</groupId>
+  <artifactId>maven-project</artifactId>
+  <version>1.0-SNAPSHOT</version>
+
+  <name>maven-project</name>
+  <url>http://www.example.com</url>
+
+  <properties>
+    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+    <maven.compiler.source>1.8</maven.compiler.source>
+    <maven.compiler.target>1.8</maven.compiler.target>
+  </properties>
+
+  <dependencies>
+    <dependency>
+      <groupId>junit</groupId>
+      <artifactId>junit</artifactId>
+      <version>4.11</version>
+      <scope>test</scope>
+    </dependency>
+    <!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-annotations -->
+    <dependency>
+        <groupId>com.fasterxml.jackson.core</groupId>
+        <artifactId>jackson-annotations</artifactId>
+        <version>2.15.0</version>
+    </dependency>
+    <dependency>
+        <groupId>com.fasterxml.jackson.core</groupId>
+        <artifactId>jackson-databind</artifactId>
+        <version>2.15.0</version>
+    </dependency>
+    <!-- https://mvnrepository.com/artifact/org.hamcrest/hamcrest-all -->
+    <dependency>
+        <groupId>org.hamcrest</groupId>
+        <artifactId>hamcrest-all</artifactId>
+        <version>1.3</version>
+        <scope>test</scope>
+    </dependency>
+  </dependencies>
+
+  <build>
+    <plugins>
+      <!-- clean lifecycle, see https://maven.apache.org/ref/current/maven-core/lifecycles.html#clean_Lifecycle -->
+      <plugin>
+        <artifactId>maven-clean-plugin</artifactId>
+        <version>3.1.0</version>
+      </plugin>
+      <!-- default lifecycle, jar packaging: see https://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_jar_packaging -->
+      <plugin>
+        <artifactId>maven-resources-plugin</artifactId>
+        <version>3.0.2</version>
+      </plugin>
+      <plugin>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <version>3.8.0</version>
+      </plugin>
+      <plugin>
+        <artifactId>maven-surefire-plugin</artifactId>
+        <version>2.22.1</version>
+      </plugin>
+      <plugin>
+        <artifactId>maven-jar-plugin</artifactId>
+        <version>3.0.2</version>
+      </plugin>
+      <plugin>
+        <artifactId>maven-install-plugin</artifactId>
+        <version>2.5.2</version>
+      </plugin>
+      <plugin>
+        <artifactId>maven-deploy-plugin</artifactId>
+        <version>2.8.2</version>
+      </plugin>
+      <plugin>
+        <groupId>com.github.eirslett</groupId>
+        <artifactId>frontend-maven-plugin</artifactId>
+        <version>1.12.1</version>
+        <configuration>
+          <workingDirectory>./scripts/modelina</workingDirectory>
+          <installDirectory>java_runtime_node</installDirectory>
+        </configuration>
+        <executions>
+          <!-- It will install nodejs and npm -->
+          <execution> 
+            <id>install node and npm</id>
+            <phase>generate-sources</phase>
+            <goals>
+              <goal>install-node-and-npm</goal>
+            </goals>
+            <configuration>
+              <nodeVersion>v18.15.0</nodeVersion>
+            </configuration>
+          </execution>
+          <execution>
+            <id>Generate sources</id>
+            <phase>generate-sources</phase>
+            <goals>
+              <goal>npm</goal>
+            </goals>
+            <configuration>
+              <arguments>run generate</arguments>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
+    </plugins>
+  </build>
+</project>

examples/integrate-modelina-into-maven/maven-project/scripts/modelina/generate.ts

@@ -0,0 +1,22 @@
+import { JAVA_JACKSON_PRESET, JavaFileGenerator } from '@asyncapi/modelina';
+import path from 'path';
+
+// Where should the models be placed relative to root maven project?
+const PACKAGE_NAME = 'java/com/mycompany/app';
+const MODEL_DIR = `src/main/${PACKAGE_NAME}`;
+
+const FINAL_OUTPUT_PATH = path.resolve(__dirname, '../../', MODEL_DIR);
+// Setup the generator and all it's configurations
+const generator = new JavaFileGenerator({
+  presets: [JAVA_JACKSON_PRESET]
+});
+
+// Load the input from file, memory, or remotely.
+// Here we just use a local AsyncAPI file
+import INPUT from '../../asyncapi.json';
+const input = INPUT;
+
+// Generate all the files
+generator.generateToFiles(input, FINAL_OUTPUT_PATH, {
+  packageName: 'com.mycompany.app'
+});