Introduce integration tests to Honeycomb

+ Add writer infrastructure initial test

Change-Id: I0c1017f55c9456f145943ca6db6221555b746c8f
Signed-off-by: Maros Marsalek <mmarsale@cisco.com>

11 files changed, 832 insertions, 196 deletions

diff --git a/common/it-parent/pom.xml b/common/it-parent/pom.xml
deleted file mode 100644
index cf3b72ab6..000000000
--- a/common/it-parent/pom.xml
+++ /dev/null
@@ -1,83 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<!--
- Copyright (c) 2015 Cisco and/or its affiliates.
- 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.
--->
-
-<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">
-
-  <parent>
-    <groupId>org.opendaylight.controller</groupId>
-    <artifactId>mdsal-it-parent</artifactId>
-    <version>1.3.2-Beryllium-SR2</version>
-    <relativePath/>
-  </parent>
-
-  <properties>
-    <nexusproxy>http://nexus.fd.io/content</nexusproxy>
-  </properties>
-
-  <modelVersion>4.0.0</modelVersion>
-  <groupId>io.fd.honeycomb.common</groupId>
-  <artifactId>it-parent</artifactId>
-  <version>1.0.0-SNAPSHOT</version>
-  <packaging>pom</packaging>
-  <build>
-    <plugins>
-      <plugin>
-        <artifactId>maven-checkstyle-plugin</artifactId>
-        <version>${checkstyle.version}</version>
-        <executions>
-          <execution>
-            <id>check-license</id>
-            <goals>
-              <goal>check</goal>
-            </goals>
-            <phase>none</phase>
-          </execution>
-        </executions>
-      </plugin>
-      <plugin>
-        <groupId>org.apache.maven.plugins</groupId>
-        <artifactId>maven-dependency-plugin</artifactId>
-        <version>2.10</version>
-        <executions>
-          <execution>
-            <id>unpack-license</id>
-            <phase>none</phase>
-            <goals><goal>unpack</goal></goals>
-          </execution>
-        </executions>
-      </plugin>
-      <plugin>
-        <groupId>org.apache.maven.plugins</groupId>
-        <artifactId>maven-compiler-plugin</artifactId>
-        <configuration>
-          <source>1.8</source>
-          <target>1.8</target>
-        </configuration>
-      </plugin>
-    </plugins>
-  </build>
-
-  <distributionManagement>
-    <repository>
-      <id>fdio-release</id>
-      <url>${nexusproxy}/repositories/fd.io.release/</url>
-    </repository>
-    <snapshotRepository>
-      <id>fdio-snapshot</id>
-      <url>${nexusproxy}/repositories/fd.io.snapshot/</url>
-    </snapshotRepository>
-  </distributionManagement>
-</project>
diff --git a/common/pom.xml b/common/pom.xml
index bb15f2d43..0ac3a74d0 100644
--- a/common/pom.xml
+++ b/common/pom.xml
@@ -29,7 +29,6 @@
     <module>api-parent</module>
     <module>features-parent</module>
     <module>impl-parent</module>
-    <module>it-parent</module>
     <module>karaf-parent</module>
   </modules>
   <!-- DO NOT install or deploy the repo root pom as it's only needed to initiate a build -->
diff --git a/v3po/it/it-test/pom.xml b/v3po/it/it-test/pom.xml
new file mode 100644
index 000000000..04e70e948
--- /dev/null
+++ b/v3po/it/it-test/pom.xml
@@ -0,0 +1,61 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+ Copyright (c) 2016 Cisco and/or its affiliates.
+ 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.
+-->
+<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">
+    <parent>
+        <artifactId>impl-parent</artifactId>
+        <groupId>io.fd.honeycomb.common</groupId>
+        <version>1.0.0-SNAPSHOT</version>
+        <relativePath>../../../common/impl-parent</relativePath>
+    </parent>
+
+    <modelVersion>4.0.0</modelVersion>
+    <groupId>io.fd.honeycomb.v3po</groupId>
+    <artifactId>honeycomb-it-test</artifactId>
+    <version>1.0.0-SNAPSHOT</version>
+
+    <dependencies>
+        <dependency>
+            <groupId>io.fd.honeycomb.v3po</groupId>
+            <artifactId>data-impl</artifactId>
+            <version>${project.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.skinny-framework</groupId>
+            <artifactId>skinny-logback</artifactId>
+            <version>1.0.8</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.mockito</groupId>
+            <artifactId>mockito-all</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>io.fd.honeycomb.v3po</groupId>
+            <artifactId>honeycomb-test-model</artifactId>
+            <version>${project.version}</version>
+        </dependency>
+    </dependencies>
+
+
+</project>
\ No newline at end of file
diff --git a/v3po/it/it-test/src/test/java/io/fd/honeycomb/v3po/data/impl/HoneycombWriteInfraTest.java b/v3po/it/it-test/src/test/java/io/fd/honeycomb/v3po/data/impl/HoneycombWriteInfraTest.java
new file mode 100644
index 000000000..f65b3e186
--- /dev/null
+++ b/v3po/it/it-test/src/test/java/io/fd/honeycomb/v3po/data/impl/HoneycombWriteInfraTest.java
@@ -0,0 +1,587 @@
+/*
+ * Copyright (c) 2016 Cisco and/or its affiliates.
+ *
+ * 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 io.fd.honeycomb.v3po.data.impl;
+
+import static org.junit.Assert.fail;
+import static org.mockito.Matchers.any;
+import static org.mockito.Matchers.eq;
+import static org.mockito.Mockito.atLeastOnce;
+import static org.mockito.Mockito.inOrder;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.verifyNoMoreInteractions;
+import static org.mockito.Mockito.when;
+
+import com.google.common.collect.Lists;
+import com.google.common.collect.Sets;
+import com.google.common.util.concurrent.Futures;
+import io.fd.honeycomb.v3po.data.DataModification;
+import io.fd.honeycomb.v3po.translate.util.write.registry.FlatWriterRegistryBuilder;
+import io.fd.honeycomb.v3po.translate.write.WriteContext;
+import io.fd.honeycomb.v3po.translate.write.Writer;
+import io.fd.honeycomb.v3po.translate.write.WriterRegistry;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+import java.util.Map;
+import javassist.ClassPool;
+import org.junit.Before;
+import org.junit.Test;
+import org.mockito.InOrder;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import org.opendaylight.controller.md.sal.binding.impl.BindingToNormalizedNodeCodec;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.$YangModuleInfoImpl;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.ComplexAugment;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.ComplexAugmentBuilder;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.ContainerWithChoice;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.ContainerWithChoiceBuilder;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.ContainerWithList;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.ContainerWithListBuilder;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.SimpleAugment;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.SimpleAugmentBuilder;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.SimpleContainer;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.SimpleContainerBuilder;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.container.with.choice.Choice;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.container.with.choice.choice.c3.C3;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.container.with.choice.choice.c3.C3Builder;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.container.with.list.ListInContainer;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.container.with.list.ListInContainerBuilder;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.container.with.list.ListInContainerKey;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.container.with.list.list.in.container.ContainerInList;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.container.with.list.list.in.container.ContainerInListBuilder;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.container.with.list.list.in.container.container.in.list.NestedList;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.container.with.list.list.in.container.container.in.list.NestedListBuilder;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.container.with.list.list.in.container.container.in.list.NestedListKey;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.simple.container.ComplexAugmentContainer;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.simple.container.ComplexAugmentContainerBuilder;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.some.attributes.ContainerFromGrouping;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.some.attributes.ContainerFromGroupingBuilder;
+import org.opendaylight.yangtools.binding.data.codec.api.BindingNormalizedNodeSerializer;
+import org.opendaylight.yangtools.binding.data.codec.gen.impl.DataObjectSerializerGenerator;
+import org.opendaylight.yangtools.binding.data.codec.gen.impl.StreamWriterGenerator;
+import org.opendaylight.yangtools.binding.data.codec.impl.BindingNormalizedNodeCodecRegistry;
+import org.opendaylight.yangtools.sal.binding.generator.impl.ModuleInfoBackedContext;
+import org.opendaylight.yangtools.sal.binding.generator.util.BindingRuntimeContext;
+import org.opendaylight.yangtools.sal.binding.generator.util.JavassistUtils;
+import org.opendaylight.yangtools.yang.binding.DataObject;
+import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
+import org.opendaylight.yangtools.yang.binding.KeyedInstanceIdentifier;
+import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
+import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
+import org.opendaylight.yangtools.yang.data.api.schema.tree.TipProducingDataTree;
+import org.opendaylight.yangtools.yang.data.api.schema.tree.TreeType;
+import org.opendaylight.yangtools.yang.data.impl.schema.tree.InMemoryDataTreeFactory;
+import org.opendaylight.yangtools.yang.model.api.SchemaContext;
+
+/**
+ * Testing honeycomb writes from data tree up to mocked writers
+ */
+public class HoneycombWriteInfraTest {
+
+    private TipProducingDataTree dataTree;
+    private BindingNormalizedNodeSerializer serializer;
+    private WriterRegistry writerRegistry;
+    private SchemaContext schemaContext;
+
+    @Mock
+    private org.opendaylight.controller.md.sal.binding.api.ReadWriteTransaction ctxTx;
+    @Mock
+    private org.opendaylight.controller.md.sal.binding.api.DataBroker contextBroker;
+
+    // Simple container
+    // ORDER = 3
+    static final InstanceIdentifier<SimpleContainer> SIMPLE_CONTAINER_ID = InstanceIdentifier.create(SimpleContainer.class);
+    Writer<SimpleContainer> simpleContainerWriter = mockWriter(SIMPLE_CONTAINER_ID);
+    // UNORDERED
+    static final InstanceIdentifier<ComplexAugment> COMPLEX_AUGMENT_ID = SIMPLE_CONTAINER_ID.augmentation(ComplexAugment.class);
+    Writer<ComplexAugment> complexAugmentWriter = mockWriter(COMPLEX_AUGMENT_ID);
+    // 1
+    static final InstanceIdentifier<ComplexAugmentContainer> COMPLEX_AUGMENT_CONTAINER_ID = COMPLEX_AUGMENT_ID.child(ComplexAugmentContainer.class);
+    Writer<ComplexAugmentContainer> complexAugmentContainerWriter = mockWriter(COMPLEX_AUGMENT_CONTAINER_ID);
+    // 2
+    static final InstanceIdentifier<SimpleAugment> SIMPLE_AUGMENT_ID = SIMPLE_CONTAINER_ID.augmentation(SimpleAugment.class);
+    Writer<SimpleAugment> simpleAugmentWriter = mockWriter(SIMPLE_AUGMENT_ID);
+
+    // Container with list
+    // 9
+    static final InstanceIdentifier<ContainerWithList> CONTAINER_WITH_LIST_ID = InstanceIdentifier.create(ContainerWithList.class);
+    Writer<ContainerWithList> containerWithListWriter = mockWriter(CONTAINER_WITH_LIST_ID);
+    // 7
+    static final InstanceIdentifier<ListInContainer> LIST_IN_CONTAINER_ID = CONTAINER_WITH_LIST_ID.child(ListInContainer.class);
+    Writer<ListInContainer> listInContainerWriter = mockWriter(LIST_IN_CONTAINER_ID);
+    // 8
+    static final InstanceIdentifier<ContainerInList> CONTAINER_IN_LIST_ID = LIST_IN_CONTAINER_ID.child(ContainerInList.class);
+    Writer<ContainerInList> containerInListWriter = mockWriter(CONTAINER_IN_LIST_ID);
+    // 6
+    static final InstanceIdentifier<NestedList> NESTED_LIST_ID = CONTAINER_IN_LIST_ID.child(NestedList.class);
+    Writer<NestedList> nestedListWriter = mockWriter(NESTED_LIST_ID);
+
+    // Container with choice
+    // 4
+    static final InstanceIdentifier<ContainerWithChoice> CONTAINER_WITH_CHOICE_ID = InstanceIdentifier.create(ContainerWithChoice.class);
+    Writer<ContainerWithChoice> containerWithChoiceWriter = mockWriter(CONTAINER_WITH_CHOICE_ID);
+    // 5
+    static final InstanceIdentifier<ContainerFromGrouping> CONTAINER_FROM_GROUPING_ID = CONTAINER_WITH_CHOICE_ID.child(ContainerFromGrouping.class);
+    Writer<ContainerFromGrouping> containerFromGroupingWriter = mockWriter(CONTAINER_FROM_GROUPING_ID);
+    // 2
+    static final InstanceIdentifier<C3> C3_ID = CONTAINER_WITH_CHOICE_ID.child(C3.class);
+    Writer<C3> c3Writer = mockWriter(C3_ID);
+
+
+    private static <D extends DataObject> Writer<D> mockWriter(final InstanceIdentifier<D> id) {
+        final Writer<D> mock = (Writer<D>) mock(Writer.class);
+        when(mock.getManagedDataObjectType()).thenReturn(id);
+        return mock;
+    }
+
+    @Before
+    public void setUp() throws Exception {
+        MockitoAnnotations.initMocks(this);
+        when(contextBroker.newReadWriteTransaction()).thenReturn(ctxTx);
+        when(ctxTx.submit()).thenReturn(Futures.immediateCheckedFuture(null));
+
+        initSerializer();
+        initDataTree();
+        initWriterRegistry();
+    }
+
+    private void initDataTree() {
+        dataTree = InMemoryDataTreeFactory.getInstance().create(TreeType.CONFIGURATION);
+        dataTree.setSchemaContext(schemaContext);
+    }
+
+    private void initSerializer() {
+        final ModuleInfoBackedContext moduleInfoBackedContext = ModuleInfoBackedContext.create();
+        moduleInfoBackedContext.addModuleInfos(Collections.singleton($YangModuleInfoImpl.getInstance()));
+        schemaContext = moduleInfoBackedContext.tryToCreateSchemaContext().get();
+
+        final DataObjectSerializerGenerator serializerGenerator = new StreamWriterGenerator(JavassistUtils.forClassPool(
+                ClassPool.getDefault()));
+        final BindingNormalizedNodeCodecRegistry codecRegistry = new BindingNormalizedNodeCodecRegistry(serializerGenerator);
+        serializer = new BindingToNormalizedNodeCodec(moduleInfoBackedContext, codecRegistry);
+        final BindingRuntimeContext ctx =
+                BindingRuntimeContext.create(moduleInfoBackedContext, schemaContext);
+        codecRegistry.onBindingRuntimeContextUpdated(ctx);
+    }
+
+    private void initWriterRegistry() {
+        writerRegistry = new FlatWriterRegistryBuilder()
+                .addWriter(complexAugmentWriter) // unordered
+                .addWriter(nestedListWriter) // 6
+                .addWriterAfter(listInContainerWriter, NESTED_LIST_ID) // 7
+                .addWriterAfter(containerInListWriter, LIST_IN_CONTAINER_ID) // 8
+                .addWriterAfter(containerWithListWriter, CONTAINER_IN_LIST_ID) // 9
+                .addWriterBefore(containerFromGroupingWriter, NESTED_LIST_ID) // 5
+                .addWriterBefore(containerWithChoiceWriter, CONTAINER_FROM_GROUPING_ID) // 4
+                .addWriterBefore(simpleContainerWriter, CONTAINER_WITH_CHOICE_ID) // 3
+                .addWriterBefore(c3Writer, SIMPLE_CONTAINER_ID) // 2
+                .addWriterBefore(simpleAugmentWriter, SIMPLE_CONTAINER_ID) // 2
+                .addWriterBefore(complexAugmentContainerWriter, Sets.newHashSet(C3_ID, SIMPLE_AUGMENT_ID)) // 1
+                .build();
+    }
+
+    @Test
+    public void testWriteEmptyNonPresenceContainer() throws Exception {
+        final ModifiableDataTreeDelegator modifiableDataTreeDelegator =
+                new ModifiableDataTreeDelegator(serializer, dataTree, writerRegistry, contextBroker);
+
+        final DataModification dataModification = modifiableDataTreeDelegator.newModification();
+        final SimpleContainer data = new SimpleContainerBuilder()
+                .build();
+
+        final Map.Entry<YangInstanceIdentifier, NormalizedNode<?, ?>> normalizedNode =
+                serializer.toNormalizedNode(SIMPLE_CONTAINER_ID, data);
+        dataModification.write(normalizedNode.getKey(), normalizedNode.getValue());
+
+        dataModification.commit();
+
+        verify(simpleContainerWriter).getManagedDataObjectType();
+        verifyNoMoreInteractions(simpleContainerWriter);
+    }
+
+    @Test
+    public void testWriteEverything() throws Exception {
+        final ModifiableDataTreeDelegator modifiableDataTreeDelegator =
+                new ModifiableDataTreeDelegator(serializer, dataTree, writerRegistry, contextBroker);
+
+        final DataModification dataModification = modifiableDataTreeDelegator.newModification();
+        // Now write everything we can
+        writeSimpleContainer(dataModification);
+        writeContainerWithChoice(dataModification);
+        writeContainerWithList(dataModification);
+        dataModification.commit();
+
+        final Writer<?>[] orderedWriters = getOrderedWriters();
+        final InOrder inOrder = inOrder(orderedWriters);
+        verifyOrderedWrites(orderedWriters, inOrder);
+    }
+
+    private void verifyOrderedWrites(final Writer<?>[] orderedWriters, final InOrder inOrder)
+            throws io.fd.honeycomb.v3po.translate.write.WriteFailedException {
+        // TODO Modifications are not produced for nodes that do not contain any actual leaves (except when choice is a child) do we need those triggers ?
+        // Unordered
+        // verify(complexAugmentWriter).update(eq(COMPLEX_AUGMENT_ID), eq(null), eq(getComplexAugment()), any(WriteContext.class));
+        // 1
+        inOrder.verify(complexAugmentContainerWriter)
+                .update(eq(COMPLEX_AUGMENT_CONTAINER_ID), eq(null), eq(getComplexAugmentContainer()), any(WriteContext.class));
+        // 2
+        inOrder.verify(c3Writer)
+                .update(eq(C3_ID), eq(null), eq(getC3()), any(WriteContext.class));
+        // 2
+        verify(simpleAugmentWriter)
+                .update(eq(SIMPLE_AUGMENT_ID), eq(null), eq(getSimpleAugment()), any(WriteContext.class));
+        // 3
+        inOrder.verify(simpleContainerWriter)
+                .update(eq(SIMPLE_CONTAINER_ID), eq(null), eq(getSimpleContainer()), any(WriteContext.class));
+        // 4
+        inOrder.verify(containerWithChoiceWriter)
+                .update(eq(CONTAINER_WITH_CHOICE_ID), eq(null), eq(getContainerWithChoiceWithComplexCase()), any(WriteContext.class));
+        // 5
+        inOrder.verify(containerFromGroupingWriter)
+                .update(eq(CONTAINER_FROM_GROUPING_ID), eq(null), eq(getContainerFromGrouping()), any(WriteContext.class));
+
+        final KeyedInstanceIdentifier<ListInContainer, ListInContainerKey> keyedListInContainer1 =
+                CONTAINER_WITH_LIST_ID.child(ListInContainer.class, new ListInContainerKey((long) 1));
+        final KeyedInstanceIdentifier<NestedList, NestedListKey> keyedNestedList1 =
+                keyedListInContainer1.child(ContainerInList.class).child(NestedList.class, new NestedListKey("1"));
+        final KeyedInstanceIdentifier<ListInContainer, ListInContainerKey> keyedListInContainer2 =
+                CONTAINER_WITH_LIST_ID.child(ListInContainer.class, new ListInContainerKey((long) 2));
+        final KeyedInstanceIdentifier<NestedList, NestedListKey> keyedNestedList2 =
+                keyedListInContainer2.child(ContainerInList.class).child(NestedList.class, new NestedListKey("2"));
+
+        // 6 - two items
+        inOrder.verify(nestedListWriter)
+                .update(eq(keyedNestedList1), eq(null), eq(getSingleNestedList("1")), any(WriteContext.class));
+        verify(nestedListWriter)
+                .update(eq(keyedNestedList2), eq(null), eq(getSingleNestedList("2")), any(WriteContext.class));
+
+        // 7 - two items
+        inOrder.verify(listInContainerWriter)
+                .update(eq(keyedListInContainer1), eq(null), eq(getSingleListInContainer((long)1)), any(WriteContext.class));
+        verify(listInContainerWriter)
+                .update(eq(keyedListInContainer2), eq(null), eq(getSingleListInContainer((long)2)), any(WriteContext.class));
+
+        // 8
+        inOrder.verify(containerInListWriter)
+                .update(eq(keyedListInContainer1.child(ContainerInList.class)), eq(null), eq(getContainerInList("1")), any(WriteContext.class));
+        verify(containerInListWriter)
+                .update(eq(keyedListInContainer2.child(ContainerInList.class)), eq(null), eq(getContainerInList("2")), any(WriteContext.class));
+
+        // 9 - Ignored because the container has no leaves, only complex child nodes
+        // inOrder.verify(containerWithListWriter)
+        // .update(eq(CONTAINER_WITH_LIST_ID), eq(null), eq(getContainerWithList()), any(WriteContext.class));
+
+        for (Writer<?> orderedWriter : orderedWriters) {
+            verify(orderedWriter).getManagedDataObjectType();
+            verifyNoMoreInteractions(orderedWriter);
+        }
+    }
+
+    private Writer<?>[] getOrderedWriters() {
+        return new Writer<?>[]{complexAugmentWriter, // Unordered
+                    complexAugmentContainerWriter, // 1
+                    c3Writer, // 2
+                    simpleAugmentWriter, // 2
+                    simpleContainerWriter, // 3
+                    containerWithChoiceWriter, // 4
+                    containerFromGroupingWriter, // 5
+                    nestedListWriter, // 6
+                    listInContainerWriter, // 7
+                    containerInListWriter, // 8
+                    containerWithListWriter};
+    }
+
+    @Test
+    public void testDeletes() throws Exception {
+        final ModifiableDataTreeDelegator modifiableDataTreeDelegator =
+                new ModifiableDataTreeDelegator(serializer, dataTree, writerRegistry, contextBroker);
+
+        DataModification dataModification = modifiableDataTreeDelegator.newModification();
+        // Now write everything we can
+        writeSimpleContainer(dataModification);
+        writeContainerWithChoice(dataModification);
+        writeContainerWithList(dataModification);
+        dataModification.commit();
+        // Verify writes to be able to verifyNoMore interactions at the end
+        verifyOrderedWrites(getOrderedWriters(), inOrder(getOrderedWriters()));
+
+        dataModification = modifiableDataTreeDelegator.newModification();
+        deleteSimpleContainer(dataModification);
+        deleteContainerWithChoice(dataModification);
+        deleteContainerWithList(dataModification);
+        dataModification.commit();
+
+        final Writer<?>[] orderedWriters = getOrderedWriters();
+        Collections.reverse(Arrays.asList(orderedWriters));
+        final InOrder inOrder = inOrder(orderedWriters);
+
+        final KeyedInstanceIdentifier<ListInContainer, ListInContainerKey> keyedListInContainer1 =
+                CONTAINER_WITH_LIST_ID.child(ListInContainer.class, new ListInContainerKey((long) 1));
+        final KeyedInstanceIdentifier<NestedList, NestedListKey> keyedNestedList1 =
+                keyedListInContainer1.child(ContainerInList.class).child(NestedList.class, new NestedListKey("1"));
+        final KeyedInstanceIdentifier<ListInContainer, ListInContainerKey> keyedListInContainer2 =
+                CONTAINER_WITH_LIST_ID.child(ListInContainer.class, new ListInContainerKey((long) 2));
+        final KeyedInstanceIdentifier<NestedList, NestedListKey> keyedNestedList2 =
+                keyedListInContainer2.child(ContainerInList.class).child(NestedList.class, new NestedListKey("2"));
+
+        // Deletes are handled in reverse order
+        // 1
+        inOrder.verify(containerInListWriter)
+                .update(eq(keyedListInContainer1.child(ContainerInList.class)), eq(getContainerInList("1")), eq(null), any(WriteContext.class));
+        verify(containerInListWriter)
+                .update(eq(keyedListInContainer2.child(ContainerInList.class)), eq(getContainerInList("2")), eq(null), any(WriteContext.class));
+
+        // 2
+        inOrder.verify(listInContainerWriter)
+                .update(eq(keyedListInContainer1), eq(getSingleListInContainer((long)1)), eq(null),  any(WriteContext.class));
+        verify(listInContainerWriter)
+                .update(eq(keyedListInContainer2), eq(getSingleListInContainer((long)2)), eq(null), any(WriteContext.class));
+
+        // 3
+        inOrder.verify(nestedListWriter)
+                .update(eq(keyedNestedList1), eq(getSingleNestedList("1")), eq(null), any(WriteContext.class));
+        verify(nestedListWriter)
+                .update(eq(keyedNestedList2), eq(getSingleNestedList("2")), eq(null), any(WriteContext.class));
+        // 4
+        inOrder.verify(containerFromGroupingWriter)
+                .update(eq(CONTAINER_FROM_GROUPING_ID), eq(getContainerFromGrouping()), eq(null), any(WriteContext.class));
+        // 5
+        inOrder.verify(containerWithChoiceWriter)
+                .update(eq(CONTAINER_WITH_CHOICE_ID), eq(getContainerWithChoiceWithComplexCase()), eq(null), any(WriteContext.class));
+        // 6
+        inOrder.verify(simpleContainerWriter)
+                .update(eq(SIMPLE_CONTAINER_ID), eq(getSimpleContainer()), eq(null), any(WriteContext.class));
+        // 7
+        verify(simpleAugmentWriter)
+                .update(eq(SIMPLE_AUGMENT_ID), eq(getSimpleAugment()), eq(null), any(WriteContext.class));
+        // 8
+        inOrder.verify(c3Writer)
+                .update(eq(C3_ID), eq(getC3()), eq(null), any(WriteContext.class));
+        // 9
+        inOrder.verify(complexAugmentContainerWriter)
+                .update(eq(COMPLEX_AUGMENT_CONTAINER_ID), eq(getComplexAugmentContainer()), eq(null), any(WriteContext.class));
+
+        for (Writer<?> orderedWriter : orderedWriters) {
+            verify(orderedWriter).getManagedDataObjectType();
+            verifyNoMoreInteractions(orderedWriter);
+        }
+    }
+
+    private void writeContainerWithList(final DataModification dataModification) {
+        final Map.Entry<YangInstanceIdentifier, NormalizedNode<?, ?>> normalizedNode =
+                serializer.toNormalizedNode(CONTAINER_WITH_LIST_ID, getContainerWithList());
+        dataModification.write(normalizedNode.getKey(), normalizedNode.getValue());
+    }
+
+    private void deleteContainerWithList(final DataModification dataModification) {
+        dataModification.delete(serializer.toYangInstanceIdentifier(CONTAINER_WITH_LIST_ID));
+    }
+
+    private ContainerWithList getContainerWithList() {
+        return new ContainerWithListBuilder()
+                .setListInContainer(getListInContainer((long)1, (long)2))
+                .build();
+    }
+
+    private List<ListInContainer> getListInContainer(final Long... keys) {
+        final ArrayList<ListInContainer> objects = Lists.newArrayList();
+        for (Long key : keys) {
+            objects.add(getSingleListInContainer(key));
+        }
+        return objects;
+    }
+
+    private ListInContainer getSingleListInContainer(final Long key) {
+        return new ListInContainerBuilder()
+                .setId(key)
+                .setContainerInList(getContainerInList(Long.toString(key)))
+                .build();
+    }
+
+    private ContainerInList getContainerInList(String... nestedKeys) {
+        return new ContainerInListBuilder()
+                .setName("inlist")
+                .setNestedList(getNestedList(nestedKeys))
+                .build();
+    }
+
+    private List<NestedList> getNestedList(String... keys) {
+        final ArrayList<NestedList> nestedList = new ArrayList<>();
+        for (String key : keys) {
+            nestedList.add(getSingleNestedList(key));
+        }
+        return nestedList;
+    }
+
+    private NestedList getSingleNestedList(final String key) {
+        return new NestedListBuilder()
+                .setNestedId(key)
+                .setNestedName(key)
+                .build();
+    }
+
+    private void writeContainerWithChoice(final DataModification dataModification) {
+        writeContainerWithChoice(dataModification, getContainerWithChoiceWithComplexCase());
+    }
+
+
+    private void deleteContainerWithChoice(final DataModification dataModification) {
+        dataModification.delete(serializer.toYangInstanceIdentifier(CONTAINER_WITH_CHOICE_ID));
+    }
+
+    private void writeContainerWithChoice(final DataModification dataModification,
+                                          final ContainerWithChoice containerWithChoice) {
+        final Map.Entry<YangInstanceIdentifier, NormalizedNode<?, ?>> normalizedNode =
+                serializer.toNormalizedNode(CONTAINER_WITH_CHOICE_ID, containerWithChoice);
+        dataModification.write(normalizedNode.getKey(), normalizedNode.getValue());
+    }
+
+    private ContainerWithChoice getContainerWithChoiceWithComplexCase() {
+        return new ContainerWithChoiceBuilder()
+                .setLeafFromGrouping("fromG")
+                .setName("name")
+                .setContainerFromGrouping(getContainerFromGrouping())
+                .setChoice(getComplexCase())
+                .build();
+    }
+
+    private Choice getComplexCase() {
+        return new org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.hc.test.rev150105.container.with.choice.choice.C3Builder()
+                .setC3(getC3())
+                .build();
+    }
+
+    private C3 getC3() {
+        return new C3Builder()
+                .setName("c3")
+                .build();
+    }
+
+    private void writeContainerFromGrouping(final DataModification dataModification) {
+        final Map.Entry<YangInstanceIdentifier, NormalizedNode<?, ?>> normalizedNode =
+                serializer.toNormalizedNode(CONTAINER_FROM_GROUPING_ID, getContainerFromGrouping());
+        dataModification.write(normalizedNode.getKey(), normalizedNode.getValue());
+    }
+
+    private ContainerFromGrouping getContainerFromGrouping() {
+        return new ContainerFromGroupingBuilder()
+                .setLeafInContainerFromGrouping(111)
+                .build();
+    }
+
+
+    private void writeSimpleContainer(final DataModification dataModification) {
+        final Map.Entry<YangInstanceIdentifier, NormalizedNode<?, ?>> normalizedNode =
+                serializer.toNormalizedNode(SIMPLE_CONTAINER_ID, getSimpleContainer());
+        dataModification.write(normalizedNode.getKey(), normalizedNode.getValue());
+    }
+
+    private void deleteSimpleContainer(final DataModification dataModification) {
+        final YangInstanceIdentifier yangId =
+                serializer.toYangInstanceIdentifier(SIMPLE_CONTAINER_ID);
+        dataModification.delete(yangId);
+    }
+
+    private SimpleContainer getSimpleContainer() {
+        return new SimpleContainerBuilder()
+                    .setSimpleContainerName("n")
+                    .addAugmentation(SimpleAugment.class, getSimpleAugment())
+                    .addAugmentation(ComplexAugment.class, getComplexAugment())
+                    .build();
+    }
+
+    private ComplexAugment getComplexAugment() {
+        return new ComplexAugmentBuilder()
+                .setComplexAugmentContainer(getComplexAugmentContainer())
+                .build();
+    }
+
+    private ComplexAugmentContainer getComplexAugmentContainer() {
+        return new ComplexAugmentContainerBuilder().setSomeLeaf("s").build();
+    }
+
+    private SimpleAugment getSimpleAugment() {
+        return new SimpleAugmentBuilder().setSimpleAugmentLeaf("a").build();
+    }
+
+    @Test
+    public void testWriteAndDeleteInTx() throws Exception {
+        final ModifiableDataTreeDelegator modifiableDataTreeDelegator =
+                new ModifiableDataTreeDelegator(serializer, dataTree, writerRegistry, contextBroker);
+
+        final DataModification dataModification = modifiableDataTreeDelegator.newModification();
+        // Now write everything we can
+        writeSimpleContainer(dataModification);
+        deleteSimpleContainer(dataModification);
+        dataModification.commit();
+
+        verify(simpleContainerWriter).getManagedDataObjectType();
+        // No modification
+        verifyNoMoreInteractions(simpleContainerWriter);
+    }
+
+    @Test
+    public void testSubtreeWriter() throws Exception {
+        writerRegistry = new FlatWriterRegistryBuilder()
+                // Handles also container from grouping
+                .addSubtreeWriter(Sets.newHashSet(CONTAINER_FROM_GROUPING_ID), containerWithChoiceWriter)
+                .build();
+
+        final ModifiableDataTreeDelegator modifiableDataTreeDelegator =
+                new ModifiableDataTreeDelegator(serializer, dataTree, writerRegistry, contextBroker);
+
+        final ContainerWithChoice containerWithChoice =
+                new ContainerWithChoiceBuilder().setContainerFromGrouping(getContainerFromGrouping()).build();
+
+        // Test write subtree node
+        DataModification dataModification = modifiableDataTreeDelegator.newModification();
+        writeContainerFromGrouping(dataModification);
+        dataModification.commit();
+
+        verify(containerWithChoiceWriter, atLeastOnce()).getManagedDataObjectType();
+        verify(containerWithChoiceWriter)
+                .update(eq(CONTAINER_WITH_CHOICE_ID), eq(null), eq(containerWithChoice), any(WriteContext.class));
+        verifyNoMoreInteractions(containerWithChoiceWriter);
+
+        // Test delete sub-node
+        dataModification = modifiableDataTreeDelegator.newModification();
+        final ContainerWithChoice containerWithChoiceEmpty = new ContainerWithChoiceBuilder().build();
+        deleteContainerFromGrouping(dataModification);
+        dataModification.commit();
+
+        verify(containerWithChoiceWriter, atLeastOnce()).getManagedDataObjectType();
+        verify(containerWithChoiceWriter)
+                .update(eq(CONTAINER_WITH_CHOICE_ID), eq(containerWithChoice), eq(containerWithChoiceEmpty), any(WriteContext.class));
+        verifyNoMoreInteractions(containerWithChoiceWriter);
+
+        // Test write with subtree node that's not handled by subtree writer
+        dataModification = modifiableDataTreeDelegator.newModification();
+        writeContainerWithChoice(dataModification);
+        try {
+            dataModification.commit();
+            fail("Missing writer for C3 should occur");
+        } catch (IllegalArgumentException e) {
+            return;
+        }
+    }
+
+    private void deleteContainerFromGrouping(final DataModification dataModification) {
+        dataModification.delete(serializer.toYangInstanceIdentifier(CONTAINER_FROM_GROUPING_ID));
+    }
+}
\ No newline at end of file
diff --git a/v3po/it/pom.xml b/v3po/it/pom.xml
index e7afb7535..e565f22df 100644
--- a/v3po/it/pom.xml
+++ b/v3po/it/pom.xml
@@ -13,36 +13,39 @@
  See the License for the specific language governing permissions and
  limitations under the License.
 -->
-
 <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">
 
-  <parent>
-    <groupId>io.fd.honeycomb.common</groupId>
-    <artifactId>it-parent</artifactId>
-    <version>1.0.0-SNAPSHOT</version>
-    <relativePath>../../common/it-parent</relativePath>
-  </parent>
-
-  <modelVersion>4.0.0</modelVersion>
-  <groupId>io.fd.honeycomb.v3po</groupId>
-  <artifactId>v3po-it</artifactId>
+  <groupId>io.fd.honeycomb.common</groupId>
+  <artifactId>honeycomb-it-aggregator</artifactId>
   <version>1.0.0-SNAPSHOT</version>
-  <packaging>bundle</packaging>
-
-  <properties>
-    <skipITs>false</skipITs>
-    <karaf.distro.groupId>io.fd.honeycomb.v3po</karaf.distro.groupId>
-    <karaf.distro.artifactId>v3po-karaf</karaf.distro.artifactId>
-    <karaf.distro.version>1.0.0-SNAPSHOT</karaf.distro.version>
-    <karaf.distro.type>zip</karaf.distro.type>
-  </properties>
-
-  <dependencies>
-    <dependency>
-      <groupId>${project.groupId}</groupId>
-      <artifactId>v3po-features</artifactId>
-      <version>${project.version}</version>
-    </dependency>
-  </dependencies>
+  <name>honeycomb</name>
+  <packaging>pom</packaging>
+  <modelVersion>4.0.0</modelVersion>
+  <prerequisites>
+    <maven>3.1.1</maven>
+  </prerequisites>
+  <modules>
+    <module>test-model</module>
+    <module>it-test</module>
+  </modules>
+  <!-- DO NOT install or deploy the repo root pom as it's only needed to initiate a build -->
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-deploy-plugin</artifactId>
+        <configuration>
+          <skip>true</skip>
+        </configuration>
+      </plugin>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-install-plugin</artifactId>
+        <configuration>
+          <skip>true</skip>
+        </configuration>
+      </plugin>
+    </plugins>
+  </build>
 
 </project>
diff --git a/v3po/it/src/test/java/io/fd/honeycomb/v3po/it/V3poIT.java b/v3po/it/src/test/java/io/fd/honeycomb/v3po/it/V3poIT.java
deleted file mode 100644
index abd282183..000000000
--- a/v3po/it/src/test/java/io/fd/honeycomb/v3po/it/V3poIT.java
+++ /dev/null
@@ -1,77 +0,0 @@
-/*
- * Copyright (c) 2015 Cisco and/or its affiliates.
- * 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 io.fd.honeycomb.v3po.it;
-
-import static org.ops4j.pax.exam.CoreOptions.composite;
-import static org.ops4j.pax.exam.CoreOptions.maven;
-import static org.ops4j.pax.exam.karaf.options.KarafDistributionOption.editConfigurationFilePut;
-
-import org.junit.Assert;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.opendaylight.controller.mdsal.it.base.AbstractMdsalTestBase;
-import org.ops4j.pax.exam.Option;
-import org.ops4j.pax.exam.junit.PaxExam;
-import org.ops4j.pax.exam.karaf.options.LogLevelOption.LogLevel;
-import org.ops4j.pax.exam.options.MavenUrlReference;
-import org.ops4j.pax.exam.spi.reactors.ExamReactorStrategy;
-import org.ops4j.pax.exam.spi.reactors.PerClass;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-@RunWith(PaxExam.class)
-@ExamReactorStrategy(PerClass.class)
-public class V3poIT extends AbstractMdsalTestBase {
-    private static final Logger LOG = LoggerFactory.getLogger(V3poIT.class);
-
-    @Override
-    public String getModuleName() {
-        return "v3po";
-    }
-
-    @Override
-    public String getInstanceName() {
-        return "v3po-default";
-    }
-
-    @Override
-    public MavenUrlReference getFeatureRepo() {
-        return maven()
-                .groupId("io.fd.honeycomb.v3po")
-                .artifactId("v3po-features")
-                .classifier("features")
-                .type("xml")
-                .versionAsInProject();
-    }
-
-    @Override
-    public String getFeatureName() {
-        return "odl-v3po-ui";
-    }
-
-    @Override
-    public Option getLoggingOption() {
-        Option option = editConfigurationFilePut(ORG_OPS4J_PAX_LOGGING_CFG,
-                logConfiguration(V3poIT.class),
-                LogLevel.INFO.name());
-        option = composite(option, super.getLoggingOption());
-        return option;
-    }
-
-    @Test
-    public void testv3poFeatureLoad() {
-        Assert.assertTrue(true);
-    }
-}
diff --git a/v3po/it/test-model/pom.xml b/v3po/it/test-model/pom.xml
new file mode 100644
index 000000000..f92109f6e
--- /dev/null
+++ b/v3po/it/test-model/pom.xml
@@ -0,0 +1,36 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+ Copyright (c) 2015 Cisco and/or its affiliates.
+ 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.
+-->
+<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">
+  <parent>
+    <groupId>io.fd.honeycomb.common</groupId>
+    <artifactId>api-parent</artifactId>
+    <version>1.0.0-SNAPSHOT</version>
+    <relativePath>../../../common/api-parent</relativePath>
+  </parent>
+
+  <modelVersion>4.0.0</modelVersion>
+  <groupId>io.fd.honeycomb.v3po</groupId>
+  <artifactId>honeycomb-test-model</artifactId>
+  <version>1.0.0-SNAPSHOT</version>
+  <packaging>bundle</packaging>
+
+  <dependencies>
+    <dependency>
+      <groupId>org.opendaylight.mdsal.model</groupId>
+      <artifactId>yang-ext</artifactId>
+    </dependency>
+  </dependencies>
+</project>
diff --git a/v3po/it/test-model/src/main/yang/hc-test.yang b/v3po/it/test-model/src/main/yang/hc-test.yang
new file mode 100644
index 000000000..204c5c089
--- /dev/null
+++ b/v3po/it/test-model/src/main/yang/hc-test.yang
@@ -0,0 +1,113 @@
+module hc-test {
+  yang-version 1;
+  namespace "urn:opendaylight:params:xml:ns:yang:hc:test";
+  prefix "hct";
+
+  revision "2015-01-05" {
+    description "Testing HC model with bindings";
+  }
+
+  import yang-ext {
+    prefix "ext";
+  }
+
+  // ORDER 3
+  container simple-container {
+    leaf simple-container-name {
+      type string;
+    }
+  }
+
+  grouping some-attributes {
+    leaf leaf-from-grouping {
+        type string;
+    }
+
+    // ORDER 5
+    container container-from-grouping {
+        leaf leaf-in-container-from-grouping {
+            type int32;
+        }
+    }
+  }
+
+  // ORDER 9 (no real attributes though)
+  container container-with-list {
+    // ORDER 7
+    list list-in-container {
+        key "id";
+
+        leaf id {
+            type uint32;
+        }
+
+        // ORDER 8
+        container container-in-list {
+            leaf name {
+                type string;
+            }
+
+            // ORDER 6
+            list nested-list {
+                key "nested-id";
+
+                leaf nested-id {
+                    type string;
+                }
+
+                leaf nested-name {
+                    type string;
+                }
+            }
+        }
+    }
+  }
+
+  // ORDER 4
+  container container-with-choice {
+    leaf name {
+        type string;
+    }
+
+    uses some-attributes;
+
+    choice choice {
+        leaf c1 {
+            type string;
+        }
+
+        leaf c2 {
+            type string;
+        }
+
+        // ORDER: 2
+        container c3 {
+            leaf name {
+                type string;
+            }
+        }
+    }
+  }
+
+  // ORDER: 2
+  augment "/hct:simple-container" {
+    ext:augment-identifier "simple-augment";
+
+    leaf simple-augment-leaf {
+        type string;
+    }
+  }
+
+  // UNORDERED
+  augment "/hct:simple-container" {
+    ext:augment-identifier "complex-augment";
+
+    // ORDER: 1
+    container complex-augment-container {
+        leaf some-leaf {
+            type string;
+        }
+    }
+  }
+
+}
diff --git a/v3po/pom.xml b/v3po/pom.xml
index 908acbdb6..a4675297d 100644
--- a/v3po/pom.xml
+++ b/v3po/pom.xml
@@ -48,7 +48,7 @@
     <module>karaf</module>
     <module>features</module>
     <module>artifacts</module>
-    <!--module>it</module-->
+    <module>it</module>
   </modules>
   <!-- DO NOT install or deploy the repo root pom as it's only needed to initiate a build -->
   <build>
diff --git a/v3po/translate-utils/src/main/java/io/fd/honeycomb/v3po/translate/util/write/registry/FlatWriterRegistry.java b/v3po/translate-utils/src/main/java/io/fd/honeycomb/v3po/translate/util/write/registry/FlatWriterRegistry.java
index 79d8eb88d..4abad23a6 100644
--- a/v3po/translate-utils/src/main/java/io/fd/honeycomb/v3po/translate/util/write/registry/FlatWriterRegistry.java
+++ b/v3po/translate-utils/src/main/java/io/fd/honeycomb/v3po/translate/util/write/registry/FlatWriterRegistry.java
@@ -17,7 +17,6 @@
 package io.fd.honeycomb.v3po.translate.util.write.registry;
 
 import static com.google.common.base.Preconditions.checkArgument;
-import static com.google.common.base.Preconditions.checkNotNull;
 
 import com.google.common.base.Optional;
 import com.google.common.collect.HashMultimap;
@@ -261,11 +260,9 @@ final class FlatWriterRegistry implements WriterRegistry {
         return !Sets.intersection(writer.getHandledChildTypes(), updates.keySet()).isEmpty();
     }
 
+    @Nullable
     private Writer<?> getWriter(@Nonnull final InstanceIdentifier<?> singleType) {
-        final Writer<?> writer = writers.get(singleType);
-        checkNotNull(writer,
-                "Unable to write %s. Missing writer. Current writers for: %s", singleType, writers.keySet());
-        return writer;
+        return writers.get(singleType);
     }
 
     @Nonnull
diff --git a/v3po/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/write/registry/FlatWriterRegistryTest.java b/v3po/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/write/registry/FlatWriterRegistryTest.java
index 7fb5779f3..df3296557 100644
--- a/v3po/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/write/registry/FlatWriterRegistryTest.java
+++ b/v3po/translate-utils/src/test/java/io/fd/honeycomb/v3po/translate/util/write/registry/FlatWriterRegistryTest.java
@@ -272,7 +272,7 @@ public class FlatWriterRegistryTest {
         updates.put(iid, DataObjectUpdate.create(iid, mock(type), mock(type)));
     }
 
-    @Test(expected = NullPointerException.class)
+    @Test(expected = IllegalArgumentException.class)
     public void testSingleUpdateMissingWriter() throws Exception {
         final FlatWriterRegistry flatWriterRegistry =
                 new FlatWriterRegistry(ImmutableMap.of());