Support for javaType and existingJavaType extensions in java-generator

CHANGELOG.md

@@ -5,6 +5,7 @@
 #### Bugs
 
 #### Improvements
+* Fix #5843: Support javaType and existingJavaType extensions in java-generator
 
 #### Dependency Upgrade
 

doc/java-generation-from-CRD.md

@@ -174,6 +174,39 @@ And the corresponding configurations of the Maven plugin are (output of `mvn hel
       The URLs to be used to download CRDs from remote locations
 ```
 
+## Extension support
+
+The `JavaType` extension allows the fully qualified name of the generated class to be specified,
+and potentially reused such as `Point` in the example snippet below. The `existingJavaType` extension
+allows the generator to make use of an existing java type, such as `Affinity` in the example snippet
+below.
+
+```
+spec:
+  versions:
+    - schema:
+        openAPIV3Schema:
+          type: object
+          properties:
+            spec:
+              type: object
+              properties:
+                affinity:
+                  type: object
+                  existingJavaType: io.fabric8.kubernetes.api.model.Affinity
+                point-A:
+                  type: object
+                  javaType: com.example.Point
+                  properties:
+                    x-position:
+                      type: integer
+                    y-position:
+                      type: integer
+                point-B:
+                  type: object
+                  existingJavaType: com.example.Point
+```
+
 ## Compiling the generated code
 
 The generated code depends on a few dependencies to successfully compile:

java-generator/core/src/main/java/io/fabric8/java/generator/nodes/AbstractJSONSchema2Pojo.java

@@ -294,6 +294,20 @@ private static AbstractJSONSchema2Pojo fromJsonSchema(
             prop.getDefault());
       case OBJECT:
         final boolean preserveUnknownFields = Boolean.TRUE.equals(prop.getXKubernetesPreserveUnknownFields());
+        // Added to support javaType and existingJavaType extensions for generating Java classes
+        boolean existingClass = false;
+        String type = null;
+        if (null != prop.getJavaType()) {
+          type = prop.getJavaType();
+        } else if (null != prop.getExistingJavaType()) {
+          type = prop.getExistingJavaType();
+          existingClass = true;
+        }
+        if (null != type) {
+          int index = type.lastIndexOf(".");
+          parentPkg = type.substring(0, Math.max(0, index));
+          key = type.substring(index + 1);
+        }
         return new JObject(
             parentPkg,
             key,
@@ -303,7 +317,8 @@ private static AbstractJSONSchema2Pojo fromJsonSchema(
             config,
             prop.getDescription(),
             isNullable,
-            prop.getDefault());
+            prop.getDefault(),
+            existingClass);
       case ENUM:
         String enumType = JAVA_LANG_STRING;
         switch (prop.getType()) {

java-generator/core/src/main/java/io/fabric8/java/generator/nodes/JObject.java

@@ -53,6 +53,7 @@ public class JObject extends AbstractJSONSchema2Pojo implements JObjectExtraAnno
   private final Set<String> deprecated = new HashSet<>();
 
   private final boolean preserveUnknownFields;
+  private final boolean existingClass; // Added to support existingJavaType extensions for generating Java classes
 
   public JObject(
       String pkg,
@@ -63,11 +64,13 @@ public JObject(
       Config config,
       String description,
       final boolean isNullable,
-      JsonNode defaultValue) {
+      JsonNode defaultValue,
+      boolean existingClass) {
     super(config, description, isNullable, defaultValue, null);
     this.required = new HashSet<>(Optional.ofNullable(required).orElse(Collections.emptyList()));
     this.fields = new HashMap<>();
     this.preserveUnknownFields = preserveUnknownFields;
+    this.existingClass = existingClass;
 
     this.pkg = (pkg == null) ? "" : pkg.trim();
     String pkgPrefix = (this.pkg.isEmpty()) ? this.pkg : this.pkg + ".";
@@ -153,6 +156,9 @@ private String getSortedFieldsAsParam(Set<String> list) {
 
   @Override
   public GeneratorResult generateJava() {
+    if (existingClass) {
+      return new GeneratorResult(Collections.emptyList());
+    }
     CompilationUnit cu = new CompilationUnit();
     if (!this.pkg.isEmpty()) {
       cu.setPackageDeclaration(new PackageDeclaration(new Name(this.pkg)));

java-generator/core/src/test/java/io/fabric8/java/generator/ApprovalTest.java

@@ -44,7 +44,8 @@ private static Stream<Arguments> getCRDGenerationInputData() {
         Arguments.of("testJokeCrd", "jokerequests-crd.yml", "JokeRequest", "JokeRequestJavaCr", new Config()),
         Arguments.of("testAkkaMicroservicesCrd", "akka-microservices-crd.yml", "AkkaMicroservice", "AkkaMicroserviceJavaCr",
             new Config()),
-        Arguments.of("testCalicoIPPoolCrd", "calico-ippool-crd.yml", "IPPool", "CalicoIPPoolCr", new Config()));
+        Arguments.of("testCalicoIPPoolCrd", "calico-ippool-crd.yml", "IPPool", "CalicoIPPoolCr", new Config()),
+        Arguments.of("testJavaType", "java-type-crd.yml", "JavaType", "JavaTypeCr", new Config()));
   }
 
   @ParameterizedTest

java-generator/core/src/test/java/io/fabric8/java/generator/GeneratorTest.java

@@ -295,7 +295,8 @@ void testEmptyObject() {
         defaultConfig,
         null,
         Boolean.FALSE,
-        null);
+        null,
+        false);
 
     // Act
     GeneratorResult res = obj.generateJava();
@@ -318,7 +319,8 @@ void testEmptyObjectWithoutNamespace() {
         defaultConfig,
         null,
         Boolean.FALSE,
-        null);
+        null,
+        false);
 
     // Act
     GeneratorResult res = obj.generateJava();
@@ -345,7 +347,8 @@ void testObjectOfPrimitives() {
         defaultConfig,
         null,
         Boolean.FALSE,
-        null);
+        null,
+        false);
 
     // Act
     GeneratorResult res = obj.generateJava();
@@ -379,7 +382,8 @@ void testObjectWithRequiredField() {
         defaultConfig,
         null,
         Boolean.FALSE,
-        null);
+        null,
+        false);
 
     // Act
     GeneratorResult res = obj.generateJava();
@@ -401,7 +405,8 @@ void testObjectWithAndWithoutGeneratedAnnotation() {
         defaultConfig,
         null,
         Boolean.FALSE,
-        null);
+        null,
+        false);
     Config config = new Config(null, null, false, new HashMap<>());
     JObject obj2 = new JObject(
         "v1alpha1",
@@ -412,7 +417,8 @@ void testObjectWithAndWithoutGeneratedAnnotation() {
         config,
         null,
         Boolean.FALSE,
-        null);
+        null,
+        false);
     String generatedAnnotationName = AbstractJSONSchema2Pojo.newGeneratedAnnotation().getNameAsString();
 
     // Act
@@ -592,7 +598,8 @@ void testArrayOfObjects() {
             defaultConfig,
             null,
             Boolean.FALSE,
-            null),
+            null,
+            false),
         defaultConfig,
         null,
         false,
@@ -620,7 +627,8 @@ void testMapOfObjects() {
             defaultConfig,
             null,
             Boolean.FALSE,
-            null),
+            null,
+            false),
         defaultConfig,
         null,
         Boolean.FALSE,
@@ -651,7 +659,8 @@ void testObjectOfObjects() {
         defaultConfig,
         null,
         Boolean.FALSE,
-        null);
+        null,
+        false);
 
     // Act
     GeneratorResult res = obj.generateJava();
@@ -681,7 +690,8 @@ void testObjectWithPreservedFields() {
         defaultConfig,
         null,
         Boolean.FALSE,
-        null);
+        null,
+        false);
 
     // Act
     GeneratorResult res = obj.generateJava();
@@ -708,7 +718,8 @@ void testConfigToGeneratePreservedUnknownFields() {
         config,
         null,
         Boolean.FALSE,
-        null);
+        null,
+        false);
 
     // Act
     GeneratorResult res = obj.generateJava();
@@ -739,7 +750,8 @@ void testObjectWithSpecialFieldNames() {
         defaultConfig,
         null,
         Boolean.FALSE,
-        null);
+        null,
+        false);
 
     // Act
     GeneratorResult res = obj.generateJava();
@@ -767,7 +779,7 @@ void testObjectNullableFieldsManagement() {
     nonNullableObj.setNullable(Boolean.FALSE);
     props.put("o2", nonNullableObj);
 
-    JObject obj = new JObject(null, "t", props, null, false, defaultConfig, null, Boolean.FALSE, null);
+    JObject obj = new JObject(null, "t", props, null, false, defaultConfig, null, Boolean.FALSE, null, false);
 
     // Act
     GeneratorResult res = obj.generateJava();
@@ -816,7 +828,7 @@ void testObjectWithAdditionalPropertiesTrue() {
     obj.setAdditionalProperties(new JSONSchemaPropsOrBool(true, null));
     props.put("o1", obj);
 
-    JObject jobj = new JObject(null, "t", props, null, false, defaultConfig, null, Boolean.FALSE, null);
+    JObject jobj = new JObject(null, "t", props, null, false, defaultConfig, null, Boolean.FALSE, null, false);
 
     // Act
     GeneratorResult res = jobj.generateJava();
@@ -850,7 +862,7 @@ void testClassNamesDisambiguationWithPackageNesting() {
     newObj2.setProperties(obj2Props);
     props.put("o1", newObj1);
     props.put("o2", newObj2);
-    JObject obj = new JObject("v1alpha1", "t", props, null, false, defaultConfig, null, Boolean.FALSE, null);
+    JObject obj = new JObject("v1alpha1", "t", props, null, false, defaultConfig, null, Boolean.FALSE, null, false);
 
     // Act
     GeneratorResult res = obj.generateJava();
@@ -905,7 +917,7 @@ void testObjectDefaultFieldsManagement() {
     objWithoutDefaultValues.setType("object");
     props.put("o2", objWithoutDefaultValues);
 
-    JObject obj = new JObject(null, "t", props, null, false, defaultConfig, null, Boolean.FALSE, null);
+    JObject obj = new JObject(null, "t", props, null, false, defaultConfig, null, Boolean.FALSE, null, false);
 
     // Act
     GeneratorResult res = obj.generateJava();
@@ -959,7 +971,7 @@ void testExactlyMoreThanOneDuplicatedFieldFailsWithException() {
     // Assert
     assertThrows(JavaGeneratorException.class, () -> {
       // Act
-      JObject obj = new JObject(null, "t", props, null, false, defaultConfig, null, Boolean.FALSE, null);
+      JObject obj = new JObject(null, "t", props, null, false, defaultConfig, null, Boolean.FALSE, null, false);
     },
         "An exception is expected to be thrown when an object contains more that one duplicated field");
   }
@@ -978,8 +990,31 @@ void testExactlyDuplicatedFieldNotMarkedAsDeprecatedFailsWithException() {
     // Assert
     assertThrows(JavaGeneratorException.class, () -> {
       // Act
-      JObject obj = new JObject(null, "t", props, null, false, defaultConfig, null, Boolean.FALSE, null);
+      JObject obj = new JObject(null, "t", props, null, false, defaultConfig, null, Boolean.FALSE, null, false);
     },
         "An exception is expected to be thrown when an object contains one duplicated field that is not marked as deprecated");
   }
+
+  @Test
+  void testExistingJavaTypeObject() {
+    // Arrange
+    JObject obj = new JObject(
+        "v1alpha1",
+        "T",
+        null,
+        null,
+        false,
+        defaultConfig,
+        null,
+        Boolean.FALSE,
+        null,
+        true);
+
+    // Act
+    GeneratorResult res = obj.generateJava();
+
+    // Assert
+    assertEquals("v1alpha1.T", obj.getType());
+    assertEquals(0, res.getTopLevelClasses().size());
+  }
 }

java-generator/core/src/test/resources/io/fabric8/java/generator/approvals/ApprovalTest.generate_withValidCrd_shouldGeneratePojos.testJavaType.approved.txt

@@ -0,0 +1,54 @@
+JavaTypeCr[0] = package org.test.v1;
+
+@io.fabric8.kubernetes.model.annotation.Version(value = "v1" , storage = true , served = true)
+@io.fabric8.kubernetes.model.annotation.Group("example.com")
+@io.fabric8.kubernetes.model.annotation.Plural("javatypes")
+@javax.annotation.processing.Generated("io.fabric8.java.generator.CRGeneratorRunner")
+public class JavaType extends io.fabric8.kubernetes.client.CustomResource<org.test.v1.JavaTypeSpec, java.lang.Void> implements io.fabric8.kubernetes.api.model.Namespaced {
+}
+
+JavaTypeCr[1] = package org.test.v1;
+
+@com.fasterxml.jackson.annotation.JsonInclude(com.fasterxml.jackson.annotation.JsonInclude.Include.NON_NULL)
+@com.fasterxml.jackson.annotation.JsonPropertyOrder({"affinity","point-A","point-B"})
+@com.fasterxml.jackson.databind.annotation.JsonDeserialize(using = com.fasterxml.jackson.databind.JsonDeserializer.None.class)
+@javax.annotation.processing.Generated("io.fabric8.java.generator.CRGeneratorRunner")
+public class JavaTypeSpec implements io.fabric8.kubernetes.api.model.KubernetesResource {
+
+    @com.fasterxml.jackson.annotation.JsonProperty("affinity")
+    @com.fasterxml.jackson.annotation.JsonSetter(nulls = com.fasterxml.jackson.annotation.Nulls.SKIP)
+    private io.fabric8.kubernetes.api.model.Affinity affinity;
+
+    public io.fabric8.kubernetes.api.model.Affinity getAffinity() {
+        return affinity;
+    }
+
+    public void setAffinity(io.fabric8.kubernetes.api.model.Affinity affinity) {
+        this.affinity = affinity;
+    }
+
+    @com.fasterxml.jackson.annotation.JsonProperty("point-A")
+    @com.fasterxml.jackson.annotation.JsonSetter(nulls = com.fasterxml.jackson.annotation.Nulls.SKIP)
+    private com.example.Point pointA;
+
+    public com.example.Point getPointA() {
+        return pointA;
+    }
+
+    public void setPointA(com.example.Point pointA) {
+        this.pointA = pointA;
+    }
+
+    @com.fasterxml.jackson.annotation.JsonProperty("point-B")
+    @com.fasterxml.jackson.annotation.JsonSetter(nulls = com.fasterxml.jackson.annotation.Nulls.SKIP)
+    private com.example.Point pointB;
+
+    public com.example.Point getPointB() {
+        return pointB;
+    }
+
+    public void setPointB(com.example.Point pointB) {
+        this.pointB = pointB;
+    }
+}
+