Support for fragments in the client

client/api/src/main/java/org/eclipse/microprofile/graphql/client/core/Argument.java

@@ -15,7 +15,6 @@
  */
 package org.eclipse.microprofile.graphql.client.core;
 
-
 import java.util.List;
 
 import static java.util.Arrays.asList;

client/api/src/main/java/org/eclipse/microprofile/graphql/client/core/Document.java

@@ -25,7 +25,7 @@ public interface Document extends Buildable {
     /*
         Static factory methods
     */
-    static Document document(Operation... operations) {
+    static Document document(FragmentOrOperation... operations) {
         Document document = getNewInstanceOf(Document.class);
 
         document.setOperations(asList(operations));
@@ -38,5 +38,5 @@ static Document document(Operation... operations) {
     */
     List<Operation> getOperations();
 
-    void setOperations(List<Operation> operations);
+    void setOperations(List<FragmentOrOperation> operations);
 }

client/api/src/main/java/org/eclipse/microprofile/graphql/client/core/Enum.java

@@ -29,7 +29,6 @@ static Enum gqlEnum(String value) {
         return gqlEnum;
     }
 
-
     /*
         Getter/Setter
     */

client/api/src/main/java/org/eclipse/microprofile/graphql/client/core/Field.java

@@ -21,7 +21,7 @@
 import static java.util.Collections.emptyList;
 import static org.eclipse.microprofile.graphql.client.core.utils.ServiceUtils.getNewInstanceOf;
 
-public interface Field extends Buildable {
+public interface Field extends FieldOrFragment {
     /*
         Static factory methods
     */
@@ -41,7 +41,7 @@ static Field field(String name) {
     }
 
     // (name, subfields)
-    static Field field(String name, Field... fields) {
+    static Field field(String name, FieldOrFragment... fields) {
         Field field = getNewInstanceOf(Field.class);
 
         field.setName(name);
@@ -84,7 +84,7 @@ static Field field(String name, List<Argument> args, Field... fields) {
 
     void setArguments(List<Argument> arguments);
 
-    List<Field> getFields();
+    List<FieldOrFragment> getFields();
 
-    void setFields(List<Field> fields);
+    void setFields(List<FieldOrFragment> fields);
 }

client/api/src/main/java/org/eclipse/microprofile/graphql/client/core/FieldOrFragment.java

@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2020 Contributors to the Eclipse Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.eclipse.microprofile.graphql.client.core;
+
+/**
+ * Represents one of these nodes in a GraphQL document:
+ * - regular field (name), for example "color"
+ * - reference to a named fragment, for example "...comparisonFields"
+ * - an inline fragment, for example ("... on Person { name } ")
+ */
+public interface FieldOrFragment extends Buildable {
+}

client/api/src/main/java/org/eclipse/microprofile/graphql/client/core/Fragment.java

@@ -0,0 +1,80 @@
+/*
+ * Copyright (c) 2020 Contributors to the Eclipse Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.eclipse.microprofile.graphql.client.core;
+
+import java.util.List;
+
+import static org.eclipse.microprofile.graphql.client.core.utils.ServiceUtils.getNewInstanceOf;
+import static java.util.Arrays.asList;
+
+/**
+ * Represents a named fragment definition in a GraphQL document. Such definition consists of a name,
+ * target type, and a set of fields.
+ */
+public interface Fragment extends FragmentOrOperation {
+    /*
+     * Static factory methods
+     */
+    static List<Fragment> fragments(Fragment... fragments) {
+        return asList(fragments);
+    }
+
+    static FragmentBuilder fragment(String name) {
+        return new FragmentBuilder(name);
+    }
+
+    /*
+     * Getter/Setter
+     */
+    String getName();
+
+    void setName(String name);
+
+    String getTargetType();
+
+    void setTargetType(String name);
+
+    List<FieldOrFragment> getFields();
+
+    void setFields(List<FieldOrFragment> fields);
+
+    class FragmentBuilder {
+
+        private String name;
+
+        private String targetType;
+
+        private List<FieldOrFragment> fields;
+
+        FragmentBuilder(String name) {
+            this.name = name;
+        }
+
+        public Fragment on(String targetType, FieldOrFragment... fields) {
+            this.targetType = targetType;
+            this.fields = asList(fields);
+            return build();
+        }
+
+        Fragment build() {
+            Fragment fragment = getNewInstanceOf(Fragment.class);
+            fragment.setName(name);
+            fragment.setTargetType(targetType);
+            fragment.setFields(fields);
+            return fragment;
+        }
+    }
+}

client/api/src/main/java/org/eclipse/microprofile/graphql/client/core/FragmentOrOperation.java

@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2020 Contributors to the Eclipse Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.eclipse.microprofile.graphql.client.core;
+
+/**
+ * Represents a node in a GraphQL document that can contain either an operation (query/mutation/subscription),
+ * or a definition of a named fragment. On the top level, a GraphQL document basically consists of a list
+ * of these nodes.
+ */
+public interface FragmentOrOperation extends Buildable {
+}

client/api/src/main/java/org/eclipse/microprofile/graphql/client/core/FragmentReference.java

@@ -0,0 +1,52 @@
+/*
+ * Copyright (c) 2020 Contributors to the Eclipse Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.eclipse.microprofile.graphql.client.core;
+
+
+import static org.eclipse.microprofile.graphql.client.core.utils.ServiceUtils.getNewInstanceOf;
+
+/**
+ * Represents a reference to a named fragment.
+ */
+public interface FragmentReference extends FieldOrFragment {
+
+    /**
+     * Create a fragment reference by specifying the name of the target fragment.
+     * In the resulting document, this will appear as `...FRAGMENTNAME`
+     */
+    static FragmentReference fragmentRef(String name) {
+        FragmentReference ref = getNewInstanceOf(FragmentReference.class);
+        ref.setName(name);
+        return ref;
+    }
+
+    /**
+     * Create a fragment reference by providing a built instance of a named fragment.
+     * This will actually only use the name of the fragment - in the resulting document,
+     * this will appear as `...FRAGMENTNAME`
+     */
+    static FragmentReference fragmentRef(Fragment fragment) {
+        FragmentReference ref = getNewInstanceOf(FragmentReference.class);
+        ref.setName(fragment.getName());
+        return ref;
+    }
+
+    String getName();
+
+    void setName(String name);
+
+}

client/api/src/main/java/org/eclipse/microprofile/graphql/client/core/InlineFragment.java

@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) 2020 Contributors to the Eclipse Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.eclipse.microprofile.graphql.client.core;
+
+import java.util.List;
+
+import static org.eclipse.microprofile.graphql.client.core.utils.ServiceUtils.getNewInstanceOf;
+import static java.util.Arrays.asList;
+
+/**
+ * Represents an inline fragment in a GraphQL document. This can be used
+ * anywhere where a field is expected (thus it implements `FieldOrFragment`).
+ */
+public interface InlineFragment extends FieldOrFragment {
+
+    static InlineFragment on(String type, FieldOrFragment... fields) {
+        InlineFragment fragment = getNewInstanceOf(InlineFragment.class);
+
+        fragment.setType(type);
+        fragment.setFields(asList(fields));
+
+        return fragment;
+    }
+
+    String getType();
+
+    void setType(String name);
+
+    List<FieldOrFragment> getFields();
+
+    void setFields(List<FieldOrFragment> fields);
+
+}

client/api/src/main/java/org/eclipse/microprofile/graphql/client/core/InputObject.java

@@ -17,8 +17,8 @@
 
 import java.util.List;
 
-import static java.util.Arrays.asList;
 import static org.eclipse.microprofile.graphql.client.core.utils.ServiceUtils.getNewInstanceOf;
+import static java.util.Arrays.asList;
 
 public interface InputObject extends Buildable {
     /*