HONEYCOMB-94 Reimplement writer registry with better ordering options

Now the registry is flat and allows for full control of writer execution order

Change-Id: I864e1d676588ffe59b596145e0829e81b1a1ed2f
Signed-off-by: Maros Marsalek <mmarsale@cisco.com>

7 files changed, 362 insertions, 91 deletions

diff --git a/v3po/translate-api/src/main/java/io/fd/honeycomb/v3po/translate/write/ChildWriter.java b/v3po/translate-api/src/main/java/io/fd/honeycomb/v3po/translate/write/ChildWriter.java
deleted file mode 100644
index b38f26983..000000000
--- a/v3po/translate-api/src/main/java/io/fd/honeycomb/v3po/translate/write/ChildWriter.java
+++ /dev/null
@@ -1,66 +0,0 @@
-/*
- * 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.translate.write;
-
-import com.google.common.annotations.Beta;
-import javax.annotation.Nonnull;
-import org.opendaylight.yangtools.yang.binding.DataObject;
-import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
-
-/**
- * Child writer allowing its parent to pass the builder object
- *
- * @param <D> Specific DataObject derived type, that is handled by this writer
- */
-@Beta
-public interface ChildWriter<D extends DataObject> extends Writer<D> {
-
-    /**
-     * Extract data object managed by this writer from parent data and perform write.
-     *
-     * @param parentId Id of parent node
-     * @param parentDataAfter Parent data from modification to extract data object from
-     * @param ctx Write context for current modification
-     */
-    void writeChild(@Nonnull final InstanceIdentifier<? extends DataObject> parentId,
-                    @Nonnull final DataObject parentDataAfter,
-                    @Nonnull final WriteContext ctx) throws WriteFailedException;
-
-    /**
-     * Extract data object managed by this writer(if necessary) from parent data and perform delete.
-     *
-     * @param parentId Id of parent node
-     * @param parentDataBefore Parent data before modification to extract data object from
-     * @param ctx Write context for current modification
-     */
-    void deleteChild(@Nonnull final InstanceIdentifier<? extends DataObject> parentId,
-                     @Nonnull final DataObject parentDataBefore,
-                     @Nonnull final WriteContext ctx) throws WriteFailedException;
-
-    /**
-     * Extract data object managed by this writer(if necessary) from parent data and perform delete.
-     *
-     * @param parentId Id of parent node
-     * @param parentDataBefore Parent data before modification to extract data object from
-     * @param parentDataAfter Parent data from modification to extract data object from
-     * @param ctx Write context for current modification
-     */
-    void updateChild(@Nonnull final InstanceIdentifier<? extends DataObject> parentId,
-                     @Nonnull final DataObject parentDataBefore,
-                     @Nonnull final DataObject parentDataAfter,
-                     @Nonnull final WriteContext ctx) throws WriteFailedException;
-}
diff --git a/v3po/translate-api/src/main/java/io/fd/honeycomb/v3po/translate/write/DataObjectUpdate.java b/v3po/translate-api/src/main/java/io/fd/honeycomb/v3po/translate/write/DataObjectUpdate.java
new file mode 100644
index 000000000..0d891ecba
--- /dev/null
+++ b/v3po/translate-api/src/main/java/io/fd/honeycomb/v3po/translate/write/DataObjectUpdate.java
@@ -0,0 +1,114 @@
+/*
+ * 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.translate.write;
+
+import static com.google.common.base.Preconditions.checkArgument;
+import static com.google.common.base.Preconditions.checkNotNull;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+import org.opendaylight.yangtools.yang.binding.DataObject;
+import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
+
+/**
+ * Simple wrapper for BA id + data before and after state. Does not allow both before and after to be null.
+ */
+public class DataObjectUpdate {
+
+    @Nonnull
+    private final InstanceIdentifier<?> id;
+    @Nullable
+    private final DataObject dataBefore;
+    @Nullable
+    private final DataObject dataAfter;
+
+    private DataObjectUpdate(@Nonnull final InstanceIdentifier<?> id,
+                             @Nullable final DataObject dataBefore,
+                             @Nullable final DataObject dataAfter) {
+        this.id = checkNotNull(id);
+        this.dataAfter = dataAfter;
+        this.dataBefore = dataBefore;
+    }
+
+    public DataObject getDataBefore() {
+        return dataBefore;
+    }
+
+    public DataObject getDataAfter() {
+        return dataAfter;
+    }
+
+    public InstanceIdentifier<?> getId() {
+        return id;
+    }
+
+    public static DataObjectUpdate create(@Nonnull final InstanceIdentifier<?> id,
+                                    @Nullable final DataObject dataBefore,
+                                    @Nullable final DataObject dataAfter) {
+        checkArgument(!(dataBefore == null && dataAfter == null), "Both before and after data are null");
+        if (dataBefore != null) {
+            checkArgument(id.getTargetType().isAssignableFrom(dataBefore.getClass()));
+        }
+        if (dataAfter != null) {
+            checkArgument(id.getTargetType().isAssignableFrom(dataAfter.getClass()));
+        }
+
+        return dataAfter == null
+                ? new DataObjectDelete(id, dataBefore)
+                : new DataObjectUpdate(id, dataBefore, dataAfter);
+    }
+
+    @Override
+    public boolean equals(final Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
+
+        final DataObjectUpdate that = (DataObjectUpdate) o;
+
+        return id.equals(that.id);
+
+    }
+
+    @Override
+    public int hashCode() {
+        return id.hashCode();
+    }
+
+    @Override
+    public String toString() {
+        return "DataObjectUpdate{" + "id=" + id
+                + ", dataBefore=" + dataBefore
+                + ", dataAfter=" + dataAfter
+                + '}';
+    }
+
+    public DataObjectUpdate reverse() {
+        return DataObjectUpdate.create(id, dataAfter, dataBefore);
+    }
+
+    public static class DataObjectDelete extends DataObjectUpdate {
+
+        private DataObjectDelete(@Nonnull final InstanceIdentifier<?> id,
+                                 @Nullable final DataObject dataBefore) {
+            super(id, dataBefore, null);
+        }
+    }
+}
diff --git a/v3po/translate-api/src/main/java/io/fd/honeycomb/v3po/translate/write/ModifiableWriterRegistry.java b/v3po/translate-api/src/main/java/io/fd/honeycomb/v3po/translate/write/ModifiableWriterRegistry.java
new file mode 100644
index 000000000..71ecbb806
--- /dev/null
+++ b/v3po/translate-api/src/main/java/io/fd/honeycomb/v3po/translate/write/ModifiableWriterRegistry.java
@@ -0,0 +1,78 @@
+/*
+ * 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.translate.write;
+
+import com.google.common.annotations.Beta;
+import java.util.Collection;
+import java.util.Set;
+import javax.annotation.Nonnull;
+import org.opendaylight.yangtools.yang.binding.DataObject;
+import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
+
+/**
+ * Mutable registry that allows adding new writers.
+ */
+@Beta
+public interface ModifiableWriterRegistry {
+
+    /**
+     * Add a writer responsible for writing only a single complex node.
+     */
+    ModifiableWriterRegistry addWriter(@Nonnull Writer<? extends DataObject> writer);
+
+    /**
+     * Add a writer responsible for writing multiple complex nodes within a subtree its responsible for.
+     * Identifiers for subtree nodes handled by a single writer have to be relative from {@link DataObject} that
+     * represents subtree root.
+     */
+    ModifiableWriterRegistry addSubtreeWriter(@Nonnull Set<InstanceIdentifier<?>> handledChildren,
+                                              @Nonnull Writer<? extends DataObject> writer);
+
+    /**
+     * Add a writer and make sure it will be executed before writer identifier by relatedType is executed.
+     */
+    ModifiableWriterRegistry addWriterBefore(@Nonnull Writer<? extends DataObject> writer,
+                                             @Nonnull InstanceIdentifier<?> relatedType);
+
+    ModifiableWriterRegistry addSubtreeWriterBefore(@Nonnull Set<InstanceIdentifier<?>> handledChildren,
+                                                    @Nonnull Writer<? extends DataObject> writer,
+                                                    @Nonnull InstanceIdentifier<?> relatedType);
+
+    ModifiableWriterRegistry addWriterBefore(@Nonnull Writer<? extends DataObject> writer,
+                                             @Nonnull Collection<InstanceIdentifier<?>> relatedTypes);
+
+    ModifiableWriterRegistry addSubtreeWriterBefore(@Nonnull Set<InstanceIdentifier<?>> handledChildren,
+                                                    @Nonnull Writer<? extends DataObject> writer,
+                                                    @Nonnull Collection<InstanceIdentifier<?>> relatedTypes);
+
+    /**
+     * Add a writer and make sure it will be executed after writer identifier by relatedType is executed.
+     */
+    ModifiableWriterRegistry addWriterAfter(@Nonnull Writer<? extends DataObject> writer,
+                                            @Nonnull InstanceIdentifier<?> relatedType);
+
+    ModifiableWriterRegistry addSubtreeWriterAfter(@Nonnull Set<InstanceIdentifier<?>> handledChildren,
+                                                   @Nonnull Writer<? extends DataObject> writer,
+                                                   @Nonnull InstanceIdentifier<?> relatedType);
+
+    ModifiableWriterRegistry addWriterAfter(@Nonnull Writer<? extends DataObject> writer,
+                                            @Nonnull Collection<InstanceIdentifier<?>> relatedTypes);
+
+    ModifiableWriterRegistry addSubtreeWriterAfter(@Nonnull Set<InstanceIdentifier<?>> handledChildren,
+                                                   @Nonnull Writer<? extends DataObject> writer,
+                                                   @Nonnull Collection<InstanceIdentifier<?>> relatedTypes);
+}
diff --git a/v3po/translate-api/src/main/java/io/fd/honeycomb/v3po/translate/write/WriterFactory.java b/v3po/translate-api/src/main/java/io/fd/honeycomb/v3po/translate/write/WriterFactory.java
new file mode 100644
index 000000000..4287964db
--- /dev/null
+++ b/v3po/translate-api/src/main/java/io/fd/honeycomb/v3po/translate/write/WriterFactory.java
@@ -0,0 +1,28 @@
+/*
+ * 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.translate.write;
+
+import com.google.common.annotations.Beta;
+
+@Beta
+public interface WriterFactory {
+
+    /**
+     * Initialize 1 or more writers and add them to provided registry.
+     */
+    void init(ModifiableWriterRegistry registry);
+}
diff --git a/v3po/translate-api/src/main/java/io/fd/honeycomb/v3po/translate/write/WriterRegistry.java b/v3po/translate-api/src/main/java/io/fd/honeycomb/v3po/translate/write/WriterRegistry.java
index d30f06d13..64735017f 100644
--- a/v3po/translate-api/src/main/java/io/fd/honeycomb/v3po/translate/write/WriterRegistry.java
+++ b/v3po/translate-api/src/main/java/io/fd/honeycomb/v3po/translate/write/WriterRegistry.java
@@ -19,47 +19,131 @@ package io.fd.honeycomb.v3po.translate.write;
 import static com.google.common.base.Preconditions.checkNotNull;
 
 import com.google.common.annotations.Beta;
-import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableSet;
+import com.google.common.collect.Multimap;
+import com.google.common.collect.Sets;
 import io.fd.honeycomb.v3po.translate.TranslationException;
-import java.util.List;
-import java.util.Map;
+import java.util.Set;
 import javax.annotation.Nonnull;
 import org.opendaylight.yangtools.yang.binding.DataObject;
 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
 
 /**
- * Special {@link Writer} capable of performing bulk updates
+ * Special {@link Writer} capable of performing bulk updates.
  */
 @Beta
 public interface WriterRegistry extends Writer<DataObject> {
 
     /**
-     * Performs bulk update
+     * Performs bulk update.
      *
      * @throws BulkUpdateException in case bulk update fails
-     * @throws TranslationException        in case some other error occurs while processing update request
+     * @throws TranslationException in case some other error occurs while processing update request
      */
-    void update(@Nonnull final Map<InstanceIdentifier<?>, DataObject> dataBefore,
-                @Nonnull final Map<InstanceIdentifier<?>, DataObject> dataAfter,
-                @Nonnull final WriteContext ctx) throws TranslationException;
+    void update(@Nonnull DataObjectUpdates updates,
+                @Nonnull WriteContext ctx) throws TranslationException;
+
+    /**
+     * Simple DTO containing updates for {@link WriterRegistry}. Currently only deletes and updates (create + update)
+     * are distinguished.
+     */
+    @Beta
+    final class DataObjectUpdates {
+
+        private final Multimap<InstanceIdentifier<?>, DataObjectUpdate> updates;
+        private final Multimap<InstanceIdentifier<?>, DataObjectUpdate.DataObjectDelete> deletes;
+
+        /**
+         * Create new instance.
+         *
+         * @param updates All updates indexed by their unkeyed {@link InstanceIdentifier}
+         * @param deletes All deletes indexed by their unkeyed {@link InstanceIdentifier}
+         */
+        public DataObjectUpdates(@Nonnull final Multimap<InstanceIdentifier<?>, DataObjectUpdate> updates,
+                                 @Nonnull final Multimap<InstanceIdentifier<?>, DataObjectUpdate.DataObjectDelete> deletes) {
+            this.deletes = deletes;
+            this.updates = updates;
+        }
+
+        public Multimap<InstanceIdentifier<?>, DataObjectUpdate> getUpdates() {
+            return updates;
+        }
+
+        public Multimap<InstanceIdentifier<?>, DataObjectUpdate.DataObjectDelete> getDeletes() {
+            return deletes;
+        }
+
+        public boolean isEmpty() {
+            return updates.isEmpty() && deletes.isEmpty();
+        }
+
+        @Override
+        public String toString() {
+            return "DataObjectUpdates{" + "updates=" + updates + ", deletes=" + deletes + '}';
+        }
+
+        /**
+         * Get a {@link Set} containing all update types from both updates as well as deletes.
+         */
+        public Set<InstanceIdentifier<?>> getTypeIntersection() {
+            return Sets.union(deletes.keySet(), updates.keySet());
+        }
+
+        /**
+         * Check whether there is only a single type of data object to be updated.
+         *
+         * @return true if there is only a single type of updates (update + delete)
+         */
+        public boolean containsOnlySingleType() {
+            return getTypeIntersection().size() == 1;
+        }
+
+        @Override
+        public boolean equals(final Object other) {
+            if (this == other) {
+                return true;
+            }
+            if (other == null || getClass() != other.getClass()) {
+                return false;
+            }
+
+            final DataObjectUpdates that = (DataObjectUpdates) other;
+
+            if (!updates.equals(that.updates)) {
+                return false;
+            }
+            return deletes.equals(that.deletes);
+
+        }
+
+        @Override
+        public int hashCode() {
+            int result = updates.hashCode();
+            result = 31 * result + deletes.hashCode();
+            return result;
+        }
+
+    }
 
     /**
      * Thrown when bulk update failed.
      */
     @Beta
-    class BulkUpdateException extends WriteFailedException {
+    class BulkUpdateException extends TranslationException {
 
         private final Reverter reverter;
+        private final Set<InstanceIdentifier<?>> failedIds;
 
         /**
          * Constructs an BulkUpdateException.
-         *
-         * @param failedId instance identifier of the data object that caused bulk update to fail.
-         * @param cause    the cause of bulk update failure
+         * @param failedIds instance identifiers of the data objects that were not processed during bulk update.
+         * @param cause the cause of bulk update failure
          */
-        public BulkUpdateException(@Nonnull final InstanceIdentifier<?> failedId, @Nonnull final Reverter reverter,
-                                   final Throwable cause) {
-            super(failedId, "Bulk update failed at " + failedId, cause);
+        public BulkUpdateException(@Nonnull final Set<InstanceIdentifier<?>> failedIds,
+                                   @Nonnull final Reverter reverter,
+                                   @Nonnull final Throwable cause) {
+            super("Bulk update failed at: " + failedIds, cause);
+            this.failedIds = failedIds;
             this.reverter = checkNotNull(reverter, "reverter should not be null");
         }
 
@@ -72,10 +156,13 @@ public interface WriterRegistry extends Writer<DataObject> {
             reverter.revert();
         }
 
+        public Set<InstanceIdentifier<?>> getFailedIds() {
+            return failedIds;
+        }
     }
 
     /**
-     * Abstraction over revert mechanism in case of a bulk update failure
+     * Abstraction over revert mechanism in case of a bulk update failure.
      */
     @Beta
     interface Reverter {
@@ -95,19 +182,19 @@ public interface WriterRegistry extends Writer<DataObject> {
         class RevertFailedException extends TranslationException {
 
             // TODO change to list of VppDataModifications to make debugging easier
-            private final List<InstanceIdentifier<?>> notRevertedChanges;
+            private final Set<InstanceIdentifier<?>> notRevertedChanges;
 
             /**
-             * Constructs an RevertFailedException with the list of changes that were not reverted.
+             * Constructs a RevertFailedException with the list of changes that were not reverted.
              *
              * @param notRevertedChanges list of changes that were not reverted
              * @param cause              the cause of revert failure
              */
-            public RevertFailedException(@Nonnull final List<InstanceIdentifier<?>> notRevertedChanges,
+            public RevertFailedException(@Nonnull final Set<InstanceIdentifier<?>> notRevertedChanges,
                                          final Throwable cause) {
                 super(cause);
                 checkNotNull(notRevertedChanges, "notRevertedChanges should not be null");
-                this.notRevertedChanges = ImmutableList.copyOf(notRevertedChanges);
+                this.notRevertedChanges = ImmutableSet.copyOf(notRevertedChanges);
             }
 
             /**
@@ -116,7 +203,7 @@ public interface WriterRegistry extends Writer<DataObject> {
              * @return list of changes that were not reverted
              */
             @Nonnull
-            public List<InstanceIdentifier<?>> getNotRevertedChanges() {
+            public Set<InstanceIdentifier<?>> getNotRevertedChanges() {
                 return notRevertedChanges;
             }
         }
diff --git a/v3po/translate-api/src/main/java/io/fd/honeycomb/v3po/translate/write/WriterRegistryBuilder.java b/v3po/translate-api/src/main/java/io/fd/honeycomb/v3po/translate/write/WriterRegistryBuilder.java
new file mode 100644
index 000000000..55ef66ec6
--- /dev/null
+++ b/v3po/translate-api/src/main/java/io/fd/honeycomb/v3po/translate/write/WriterRegistryBuilder.java
@@ -0,0 +1,25 @@
+/*
+ * 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.translate.write;
+
+/**
+ * Builder for writer registries.
+ */
+public interface WriterRegistryBuilder {
+
+    WriterRegistry build();
+}
diff --git a/v3po/translate-api/src/main/yang/translate-api.yang b/v3po/translate-api/src/main/yang/translate-api.yang
index 4a8093ab8..414ee20e1 100644
--- a/v3po/translate-api/src/main/yang/translate-api.yang
+++ b/v3po/translate-api/src/main/yang/translate-api.yang
@@ -24,14 +24,19 @@ module translate-api {
         config:java-class io.fd.honeycomb.v3po.translate.read.ReaderRegistry;
     }
 
-    identity honeycomb-writer {
+    identity honeycomb-writer-factory {
         base "config:service-type";
-        config:java-class io.fd.honeycomb.v3po.translate.write.Writer;
+        config:java-class io.fd.honeycomb.v3po.translate.write.WriterFactory;
     }
 
     identity honeycomb-writer-registry {
         base "config:service-type";
-        config:java-class io.fd.honeycomb.v3po.translate.write.WriterRegistry;
+        config:java-class io.fd.honeycomb.v3po.translate.write.ModifiableWriterRegistry;
+    }
+
+    identity honeycomb-writer-registry-builder {
+        base "config:service-type";
+        config:java-class io.fd.honeycomb.v3po.translate.write.WriterRegistryBuilder;
     }
 
     identity honeycomb-mapping-context {