HONEYCOMB-61: Restore configuration and context from persisted files

Change-Id: I6edce127f8895f5d65998b4be71a0a111ca2e8bb
Signed-off-by: Maros Marsalek <mmarsale@cisco.com>

4 files changed, 117 insertions, 0 deletions

diff --git a/v3po/vpp-cfg-init/src/main/java/io/fd/honeycomb/v3po/vpp/data/init/DataTreeInitializer.java b/v3po/vpp-cfg-init/src/main/java/io/fd/honeycomb/v3po/vpp/data/init/DataTreeInitializer.java
index 3cb6f14e4..d760401f9 100644
--- a/v3po/vpp-cfg-init/src/main/java/io/fd/honeycomb/v3po/vpp/data/init/DataTreeInitializer.java
+++ b/v3po/vpp-cfg-init/src/main/java/io/fd/honeycomb/v3po/vpp/data/init/DataTreeInitializer.java
@@ -43,5 +43,9 @@ public interface DataTreeInitializer extends AutoCloseable {
         public InitializeException(final String message, final Throwable cause) {
             super(message, cause);
         }
+
+        public InitializeException(final String msg) {
+            super(msg);
+        }
     }
 }
diff --git a/v3po/vpp-cfg-init/src/main/java/io/fd/honeycomb/v3po/vpp/data/init/InterfacesInitializer.java b/v3po/vpp-cfg-init/src/main/java/io/fd/honeycomb/v3po/vpp/data/init/InterfacesInitializer.java
index fde2a2893..9ecbe0c13 100644
--- a/v3po/vpp-cfg-init/src/main/java/io/fd/honeycomb/v3po/vpp/data/init/InterfacesInitializer.java
+++ b/v3po/vpp-cfg-init/src/main/java/io/fd/honeycomb/v3po/vpp/data/init/InterfacesInitializer.java
@@ -43,6 +43,8 @@ public class InterfacesInitializer extends AbstractDataTreeConverter<InterfacesS
                 InstanceIdentifier.create(Interfaces.class));
     }
 
+    // TODO move to v3po2vpp
+
     @Override
     protected Interfaces convert(final InterfacesState operationalData) {
         LOG.debug("InterfacesInitializer.convert()");
diff --git a/v3po/vpp-cfg-init/src/main/java/io/fd/honeycomb/v3po/vpp/data/init/RestoringInitializer.java b/v3po/vpp-cfg-init/src/main/java/io/fd/honeycomb/v3po/vpp/data/init/RestoringInitializer.java
new file mode 100644
index 000000000..eed22313c
--- /dev/null
+++ b/v3po/vpp-cfg-init/src/main/java/io/fd/honeycomb/v3po/vpp/data/init/RestoringInitializer.java
@@ -0,0 +1,109 @@
+/*
+ * 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.vpp.data.init;
+
+import static com.google.common.base.Preconditions.checkArgument;
+
+import io.fd.honeycomb.v3po.translate.util.JsonUtils;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.StandardOpenOption;
+import javax.annotation.Nonnull;
+import org.opendaylight.controller.md.sal.common.api.data.LogicalDatastoreType;
+import org.opendaylight.controller.md.sal.common.api.data.TransactionCommitFailedException;
+import org.opendaylight.controller.md.sal.dom.api.DOMDataBroker;
+import org.opendaylight.controller.md.sal.dom.api.DOMDataWriteTransaction;
+import org.opendaylight.controller.sal.core.api.model.SchemaService;
+import org.opendaylight.yang.gen.v1.urn.honeycomb.params.xml.ns.yang.vpp.data.init.rev160407.RestorationType;
+import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
+import org.opendaylight.yangtools.yang.data.api.schema.ContainerNode;
+import org.opendaylight.yangtools.yang.data.api.schema.DataContainerChild;
+
+public class RestoringInitializer implements DataTreeInitializer {
+
+    private final SchemaService schemaService;
+    private final Path path;
+    private final DOMDataBroker dataTree;
+    private final RestorationType restorationType;
+    private final LogicalDatastoreType datastoreType;
+
+    public RestoringInitializer(@Nonnull final SchemaService schemaService,
+                                @Nonnull final Path path,
+                                @Nonnull final DOMDataBroker dataTree,
+                                @Nonnull final RestorationType restorationType,
+                                @Nonnull final LogicalDatastoreType datastoreType) {
+        this.schemaService = schemaService;
+        this.datastoreType = datastoreType;
+        this.path = checkStorage(path);
+        this.dataTree = dataTree;
+        this.restorationType = restorationType;
+    }
+
+    private Path checkStorage(final Path path) {
+        try {
+            if(Files.exists(path)) {
+                checkArgument(!Files.isDirectory(path), "File %s is a directory", path);
+                checkArgument(Files.isReadable(path), "File %s is not readable", path);
+            } else {
+                return checkStorage(Files.createFile(path));
+            }
+        } catch (IOException e) {
+            throw new IllegalArgumentException("Cannot use " + path + " for restoring data", e);
+        }
+
+        return path;
+    }
+
+    @Override
+    public void initialize() throws InitializeException {
+        if(!Files.exists(path)) {
+            return;
+        }
+
+        try {
+            final ContainerNode containerNode = JsonUtils
+                .readJsonRoot(schemaService.getGlobalContext(), Files.newInputStream(path, StandardOpenOption.READ));
+
+            final DOMDataWriteTransaction domDataWriteTransaction = dataTree.newWriteOnlyTransaction();
+            for (DataContainerChild<? extends YangInstanceIdentifier.PathArgument, ?> dataContainerChild : containerNode
+                .getValue()) {
+                final YangInstanceIdentifier iid = YangInstanceIdentifier.create(dataContainerChild.getIdentifier());
+                switch (restorationType) {
+                    case Merge:
+                        domDataWriteTransaction.merge(datastoreType, iid, dataContainerChild);
+                        break;
+                    case Put:
+                        domDataWriteTransaction.put(datastoreType, iid, dataContainerChild);
+                        break;
+                    default:
+                        throw new InitializeException(
+                            "Unable to initialize data using " + restorationType + " restoration strategy. Unsupported");
+                }
+            }
+
+            // Block here to prevent subsequent initializers processing before context is fully restored
+            domDataWriteTransaction.submit().checkedGet();
+
+        } catch (IOException | TransactionCommitFailedException e) {
+            throw new InitializeException("Unable to restore data from " + path, e);
+        }
+    }
+
+    @Override
+    public void close() {}
+}
diff --git a/v3po/vpp-cfg-init/src/main/java/io/fd/honeycomb/v3po/vpp/data/init/VppInitializer.java b/v3po/vpp-cfg-init/src/main/java/io/fd/honeycomb/v3po/vpp/data/init/VppInitializer.java
index 77bb3a563..d7a67870a 100644
--- a/v3po/vpp-cfg-init/src/main/java/io/fd/honeycomb/v3po/vpp/data/init/VppInitializer.java
+++ b/v3po/vpp-cfg-init/src/main/java/io/fd/honeycomb/v3po/vpp/data/init/VppInitializer.java
@@ -42,6 +42,8 @@ public class VppInitializer extends AbstractDataTreeConverter<VppState, Vpp> {
         super(bindingDataBroker, InstanceIdentifier.create(VppState.class), InstanceIdentifier.create(Vpp.class));
     }
 
+    // TODO move to v3po2vpp
+
     @Override
     protected Vpp convert(final VppState operationalData) {
         LOG.debug("VppInitializer.convert()");