HONEYCOMB-61: Config persister

Add PersistingDataTree adapter for in memory config data tree
Using JSON NormalizedNode writers from ODL

Change-Id: Ida91fe6aa34aaeaedcd061ba1551afe49bbddbbb
Signed-off-by: Maros Marsalek <mmarsale@cisco.com>

3 files changed, 158 insertions, 0 deletions

diff --git a/v3po/data-impl/src/test/java/io/fd/honeycomb/v3po/data/impl/PersistingDataTreeAdapterTest.java b/v3po/data-impl/src/test/java/io/fd/honeycomb/v3po/data/impl/PersistingDataTreeAdapterTest.java
new file mode 100644
index 000000000..986d7cfb1
--- /dev/null
+++ b/v3po/data-impl/src/test/java/io/fd/honeycomb/v3po/data/impl/PersistingDataTreeAdapterTest.java
@@ -0,0 +1,137 @@
+/*
+ * 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.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+import static org.mockito.Matchers.any;
+import static org.mockito.Mockito.doReturn;
+import static org.mockito.Mockito.doThrow;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+
+import com.google.common.io.ByteStreams;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import org.junit.Before;
+import org.junit.Test;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import org.opendaylight.controller.sal.core.api.model.SchemaService;
+import org.opendaylight.yangtools.yang.common.QName;
+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.DataTree;
+import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidate;
+import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeSnapshot;
+import org.opendaylight.yangtools.yang.data.impl.schema.Builders;
+import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNodes;
+import org.opendaylight.yangtools.yang.parser.stmt.reactor.CrossSourceStatementReactor;
+import org.opendaylight.yangtools.yang.parser.stmt.rfc6020.YangInferencePipeline;
+import org.opendaylight.yangtools.yang.parser.stmt.rfc6020.YangStatementSourceImpl;
+import org.opendaylight.yangtools.yang.parser.stmt.rfc6020.effective.EffectiveSchemaContext;
+
+public class PersistingDataTreeAdapterTest {
+
+    public static final String NAMESPACE = "urn:opendaylight:params:xml:ns:yang:test:persistence";
+
+    // The root QNAME can be anything, onyl its children are iterated
+    private static final QName ROOT_QNAME = QName.create("random",  "data");
+    private static final QName TOP_CONTAINER_NAME = QName.create(NAMESPACE, "2015-01-05", "top-container");
+    private static final QName STRING_LEAF_QNAME = QName.create(TOP_CONTAINER_NAME, "string");
+
+    @Mock
+    private DataTree delegatingDataTree;
+    @Mock
+    private SchemaService schemaService;
+    @Mock
+    private DataTreeSnapshot snapshot;
+
+    private Path tmpPersistFile;
+
+    private PersistingDataTreeAdapter persistingDataTreeAdapter;
+
+    @Before
+    public void setUp() throws Exception {
+        MockitoAnnotations.initMocks(this);
+        tmpPersistFile = Files.createTempFile("testing-hc-persistence", "json");
+
+        // Build test yang schemas
+        final CrossSourceStatementReactor.BuildAction buildAction = YangInferencePipeline.RFC6020_REACTOR.newBuild();
+        buildAction.addSource(new YangStatementSourceImpl(getClass().getResourceAsStream("/test-persistence.yang")));
+        final EffectiveSchemaContext effectiveSchemaContext = buildAction.buildEffective();
+        doReturn(effectiveSchemaContext).when(schemaService).getGlobalContext();
+
+        persistingDataTreeAdapter = new PersistingDataTreeAdapter(delegatingDataTree, schemaService, tmpPersistFile);
+    }
+
+    @Test
+    public void testPersist() throws Exception {
+        doReturn(snapshot).when(delegatingDataTree).takeSnapshot();
+
+        NormalizedNode<?, ?> data = getData("testing");
+        doReturn(com.google.common.base.Optional.of(data)).when(snapshot).readNode(YangInstanceIdentifier.EMPTY);
+        persistingDataTreeAdapter.commit(null);
+        assertTrue(Files.exists(tmpPersistFile));
+
+        String persisted = new String(Files.readAllBytes(tmpPersistFile));
+        String expected =
+            new String(ByteStreams.toByteArray(getClass().getResourceAsStream("/expected-persisted-output.txt")));
+
+        assertEquals(expected, persisted);
+
+        data = getData("testing2");
+        doReturn(com.google.common.base.Optional.of(data)).when(snapshot).readNode(YangInstanceIdentifier.EMPTY);
+        persistingDataTreeAdapter.commit(null);
+
+        verify(delegatingDataTree, times(2)).commit(null);
+
+        persisted = new String(Files.readAllBytes(tmpPersistFile));
+        assertEquals(expected.replace("testing", "testing2"), persisted);
+
+        persistingDataTreeAdapter.close();
+
+        // File has to stay even after close
+        assertTrue(Files.exists(tmpPersistFile));
+    }
+
+    @Test
+    public void testNoPersistOnFailure() throws Exception {
+        doThrow(new IllegalStateException("testing errors")).when(delegatingDataTree).commit(any(DataTreeCandidate.class));
+
+        try {
+            persistingDataTreeAdapter.commit(null);
+            fail("Exception expected");
+        } catch (IllegalStateException e) {
+            assertFalse(Files.exists(tmpPersistFile));
+            verify(delegatingDataTree, times(0)).takeSnapshot();
+            verify(delegatingDataTree).commit(any(DataTreeCandidate.class));
+        }
+    }
+
+    private NormalizedNode<?, ?> getData(final String stringValue) {
+        return Builders.containerBuilder()
+                .withNodeIdentifier(new YangInstanceIdentifier.NodeIdentifier(ROOT_QNAME))
+                .withChild(Builders.containerBuilder()
+                    .withNodeIdentifier(new YangInstanceIdentifier.NodeIdentifier(TOP_CONTAINER_NAME))
+                    .withChild(ImmutableNodes.leafNode(STRING_LEAF_QNAME, stringValue))
+                    .build())
+                .build();
+    }
+}
\ No newline at end of file
diff --git a/v3po/data-impl/src/test/resources/expected-persisted-output.txt b/v3po/data-impl/src/test/resources/expected-persisted-output.txt
new file mode 100644
index 000000000..fb21d61e8
--- /dev/null
+++ b/v3po/data-impl/src/test/resources/expected-persisted-output.txt
@@ -0,0 +1,5 @@
+{
+  "test-persistence:top-container": {
+    "string": "testing"
+  }
+}
\ No newline at end of file
diff --git a/v3po/data-impl/src/test/resources/test-persistence.yang b/v3po/data-impl/src/test/resources/test-persistence.yang
new file mode 100644
index 000000000..b7dbbb1bc
--- /dev/null
+++ b/v3po/data-impl/src/test/resources/test-persistence.yang
@@ -0,0 +1,16 @@
+module test-persistence {
+    yang-version 1;
+    namespace "urn:opendaylight:params:xml:ns:yang:test:persistence";
+    prefix "tp";
+
+    revision "2015-01-05" {
+        description "Initial revision";
+    }
+
+    container top-container {
+        leaf string {
+            type string;
+        }
+    }
+
+}