Add distributed lock primitive

Change-Id: I60f4581d5acb5fc9b9a21d4191874bb56348af58
diff --git a/core/api/src/main/java/org/onosproject/store/primitives/DefaultDistributedLock.java b/core/api/src/main/java/org/onosproject/store/primitives/DefaultDistributedLock.java
new file mode 100644
index 0000000..8e48771
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/store/primitives/DefaultDistributedLock.java
@@ -0,0 +1,80 @@
+/*
+ * Copyright 2018-present Open Networking 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.onosproject.store.primitives;
+
+import java.time.Duration;
+import java.util.Optional;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
+
+import org.onosproject.store.service.AsyncDistributedLock;
+import org.onosproject.store.service.DistributedLock;
+import org.onosproject.store.service.StorageException;
+import org.onosproject.store.service.Synchronous;
+import org.onosproject.store.service.Version;
+
+/**
+ * Default implementation for a {@code DistributedLock} backed by a {@link AsyncDistributedLock}.
+ */
+public class DefaultDistributedLock extends Synchronous<AsyncDistributedLock> implements DistributedLock {
+
+    private final AsyncDistributedLock asyncLock;
+    private final long operationTimeoutMillis;
+
+    public DefaultDistributedLock(AsyncDistributedLock asyncLock, long operationTimeoutMillis) {
+        super(asyncLock);
+        this.asyncLock = asyncLock;
+        this.operationTimeoutMillis = operationTimeoutMillis;
+    }
+
+    @Override
+    public Version lock() {
+        return complete(asyncLock.lock());
+    }
+
+    @Override
+    public Optional<Version> tryLock() {
+        return complete(asyncLock.tryLock());
+    }
+
+    @Override
+    public Optional<Version> tryLock(Duration timeout) {
+        return complete(asyncLock.tryLock(timeout));
+    }
+
+    @Override
+    public void unlock() {
+        complete(asyncLock.unlock());
+    }
+
+    private <T> T complete(CompletableFuture<T> future) {
+        if (operationTimeoutMillis == -1) {
+            return future.join();
+        }
+        try {
+            return future.get(operationTimeoutMillis, TimeUnit.MILLISECONDS);
+        } catch (InterruptedException e) {
+            Thread.currentThread().interrupt();
+            throw new StorageException.Interrupted();
+        } catch (TimeoutException e) {
+            throw new StorageException.Timeout();
+        } catch (ExecutionException e) {
+            throw new StorageException(e.getCause());
+        }
+    }
+}
diff --git a/core/api/src/main/java/org/onosproject/store/primitives/DistributedPrimitiveCreator.java b/core/api/src/main/java/org/onosproject/store/primitives/DistributedPrimitiveCreator.java
index 5fad35a..1e68bdb 100644
--- a/core/api/src/main/java/org/onosproject/store/primitives/DistributedPrimitiveCreator.java
+++ b/core/api/src/main/java/org/onosproject/store/primitives/DistributedPrimitiveCreator.java
@@ -25,6 +25,7 @@
 import org.onosproject.store.service.AsyncConsistentMap;
 import org.onosproject.store.service.AsyncConsistentMultimap;
 import org.onosproject.store.service.AsyncConsistentTreeMap;
+import org.onosproject.store.service.AsyncDistributedLock;
 import org.onosproject.store.service.AsyncDistributedSet;
 import org.onosproject.store.service.AsyncDocumentTree;
 import org.onosproject.store.service.AsyncLeaderElector;
@@ -118,6 +119,14 @@
     <E> AsyncDistributedSet<E> newAsyncDistributedSet(String name, Serializer serializer);
 
     /**
+     * Creates a new {@code AsyncDistributedLock}.
+     *
+     * @param name lock name
+     * @return lock
+     */
+    AsyncDistributedLock newAsyncDistributedLock(String name);
+
+    /**
      * Creates a new {@code AsyncLeaderElector}.
      *
      * @param name leader elector name
diff --git a/core/api/src/main/java/org/onosproject/store/service/AsyncDistributedLock.java b/core/api/src/main/java/org/onosproject/store/service/AsyncDistributedLock.java
new file mode 100644
index 0000000..be35b5e
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/store/service/AsyncDistributedLock.java
@@ -0,0 +1,69 @@
+/*
+ * Copyright 2018-present Open Networking 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.onosproject.store.service;
+
+import java.time.Duration;
+import java.util.Optional;
+import java.util.concurrent.CompletableFuture;
+
+import org.onosproject.store.primitives.DefaultDistributedLock;
+
+/**
+ * Asynchronous lock primitive.
+ */
+public interface AsyncDistributedLock extends DistributedPrimitive {
+    @Override
+    default Type primitiveType() {
+        return Type.LOCK;
+    }
+
+    /**
+     * Acquires the lock, blocking until it's available.
+     *
+     * @return future to be completed once the lock has been acquired
+     */
+    CompletableFuture<Version> lock();
+
+    /**
+     * Attempts to acquire the lock.
+     *
+     * @return future to be completed with a boolean indicating whether the lock was acquired
+     */
+    CompletableFuture<Optional<Version>> tryLock();
+
+    /**
+     * Attempts to acquire the lock for a specified amount of time.
+     *
+     * @param timeout the timeout after which to give up attempting to acquire the lock
+     * @return future to be completed with a boolean indicating whether the lock was acquired
+     */
+    CompletableFuture<Optional<Version>> tryLock(Duration timeout);
+
+    /**
+     * Unlocks the lock.
+     *
+     * @return future to be completed once the lock has been released
+     */
+    CompletableFuture<Void> unlock();
+
+    default DistributedLock asLock() {
+        return asLock(-1);
+    }
+
+    default DistributedLock asLock(long timeoutMillis) {
+        return new DefaultDistributedLock(this, timeoutMillis);
+    }
+}
diff --git a/core/api/src/main/java/org/onosproject/store/service/DistributedLock.java b/core/api/src/main/java/org/onosproject/store/service/DistributedLock.java
new file mode 100644
index 0000000..cce53ff
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/store/service/DistributedLock.java
@@ -0,0 +1,56 @@
+/*
+ * Copyright 2018-present Open Networking 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.onosproject.store.service;
+
+import java.time.Duration;
+import java.util.Optional;
+
+/**
+ * Asynchronous lock primitive.
+ */
+public interface DistributedLock extends DistributedPrimitive {
+    @Override
+    default Type primitiveType() {
+        return Type.LOCK;
+    }
+
+    /**
+     * Acquires the lock, blocking until it's available.
+     *
+     * @return the acquired lock version
+     */
+    Version lock();
+
+    /**
+     * Attempts to acquire the lock.
+     *
+     * @return indicates whether the lock was acquired
+     */
+    Optional<Version> tryLock();
+
+    /**
+     * Attempts to acquire the lock for a specified amount of time.
+     *
+     * @param timeout the timeout after which to give up attempting to acquire the lock
+     * @return indicates whether the lock was acquired
+     */
+    Optional<Version> tryLock(Duration timeout);
+
+    /**
+     * Unlocks the lock.
+     */
+    void unlock();
+}
diff --git a/core/api/src/main/java/org/onosproject/store/service/DistributedLockBuilder.java b/core/api/src/main/java/org/onosproject/store/service/DistributedLockBuilder.java
new file mode 100644
index 0000000..7e61c6a
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/store/service/DistributedLockBuilder.java
@@ -0,0 +1,28 @@
+/*
+ * Copyright 2018-present Open Networking 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.onosproject.store.service;
+
+import org.onosproject.store.primitives.DistributedPrimitiveBuilder;
+
+/**
+ * Builder for DistributedLock.
+ */
+public abstract class DistributedLockBuilder
+    extends DistributedPrimitiveBuilder<DistributedLockBuilder, AsyncDistributedLock> {
+    public DistributedLockBuilder() {
+        super(DistributedPrimitive.Type.LOCK);
+    }
+}
\ No newline at end of file
diff --git a/core/api/src/main/java/org/onosproject/store/service/DistributedPrimitive.java b/core/api/src/main/java/org/onosproject/store/service/DistributedPrimitive.java
index 8a440f3..620e16d 100644
--- a/core/api/src/main/java/org/onosproject/store/service/DistributedPrimitive.java
+++ b/core/api/src/main/java/org/onosproject/store/service/DistributedPrimitive.java
@@ -99,7 +99,12 @@
         /**
          * Transaction Context.
          */
-        TRANSACTION_CONTEXT
+        TRANSACTION_CONTEXT,
+
+        /**
+         * Distributed lock.
+         */
+        LOCK,
     }
 
     /**
diff --git a/core/api/src/main/java/org/onosproject/store/service/StorageService.java b/core/api/src/main/java/org/onosproject/store/service/StorageService.java
index 94843fc..2dd42fa 100644
--- a/core/api/src/main/java/org/onosproject/store/service/StorageService.java
+++ b/core/api/src/main/java/org/onosproject/store/service/StorageService.java
@@ -24,4 +24,201 @@
  * this service for their distributed state management and coordination.
  */
 public interface StorageService extends PrimitiveService {
+
+    /**
+     * Creates a new EventuallyConsistentMapBuilder.
+     *
+     * @param <K> key type
+     * @param <V> value type
+     * @return builder for an eventually consistent map
+     */
+    <K, V> EventuallyConsistentMapBuilder<K, V> eventuallyConsistentMapBuilder();
+
+    /**
+     * Creates a new ConsistentMapBuilder.
+     *
+     * @param <K> key type
+     * @param <V> value type
+     * @return builder for a consistent map
+     */
+    <K, V> ConsistentMapBuilder<K, V> consistentMapBuilder();
+
+    /**
+     * Creates a new ConsistentMapBuilder.
+     *
+     * @param <V> value type
+     * @return builder for a consistent map
+     */
+    <V> DocumentTreeBuilder<V> documentTreeBuilder();
+
+    /**
+     * Creates a new {@code AsyncConsistentTreeMapBuilder}.
+     *
+     * @param <V> value type
+     * @return builder for a async consistent tree map
+     */
+    <V> ConsistentTreeMapBuilder<V> consistentTreeMapBuilder();
+
+    /**
+     * Creates a new {@code AsyncConsistentSetMultimapBuilder}.
+     *
+     * @param <K> key type
+     * @param <V> value type
+     * @return builder for a set based async consistent multimap
+     */
+    <K, V> ConsistentMultimapBuilder<K, V> consistentMultimapBuilder();
+
+    /**
+     * Creates a new {@code AtomicCounterMapBuilder}.
+     *
+     * @param <K> key type
+     * @return builder for an atomic counter map
+     */
+    <K> AtomicCounterMapBuilder<K> atomicCounterMapBuilder();
+
+    /**
+     * Creates a new DistributedSetBuilder.
+     *
+     * @param <E> set element type
+     * @return builder for an distributed set
+     */
+    <E> DistributedSetBuilder<E> setBuilder();
+
+    /**
+     * Creates a new AtomicCounterBuilder.
+     *
+     * @return atomic counter builder
+     */
+    AtomicCounterBuilder atomicCounterBuilder();
+
+    /**
+     * Creates a new AtomicIdGeneratorBuilder.
+     *
+     * @return atomic ID generator builder
+     */
+    AtomicIdGeneratorBuilder atomicIdGeneratorBuilder();
+
+    /**
+     * Creates a new AtomicValueBuilder.
+     *
+     * @param <V> atomic value type
+     * @return atomic value builder
+     */
+    <V> AtomicValueBuilder<V> atomicValueBuilder();
+
+    /**
+     * Creates a new DistributedLockBuilder.
+     *
+     * @return lock builder
+     */
+    DistributedLockBuilder lockBuilder();
+
+    /**
+     * Creates a new LeaderElectorBuilder.
+     *
+     * @return leader elector builder
+     */
+    LeaderElectorBuilder leaderElectorBuilder();
+
+    /**
+     * Creates a new transaction context builder.
+     *
+     * @return a builder for a transaction context.
+     */
+    TransactionContextBuilder transactionContextBuilder();
+
+    /**
+     * Returns an instance of {@code AsyncAtomicCounter} with specified name.
+     * @param name counter name
+     *
+     * @return AsyncAtomicCounter instance
+     */
+    default AsyncAtomicCounter getAsyncAtomicCounter(String name) {
+        return atomicCounterBuilder().withName(name).build();
+    }
+
+    /**
+     * Returns an instance of {@code AsyncAtomicIdGenerator} with specified name.
+     *
+     * @param name ID generator name
+     * @return AsyncAtomicIdGenerator instance
+     */
+    default AsyncAtomicIdGenerator getAsyncAtomicIdGenerator(String name) {
+        return atomicIdGeneratorBuilder().withName(name).build();
+    }
+
+    /**
+     * Returns an instance of {@code AtomicCounter} with specified name.
+     * @param name counter name
+     *
+     * @return AtomicCounter instance
+     */
+    default AtomicCounter getAtomicCounter(String name) {
+        return getAsyncAtomicCounter(name).asAtomicCounter();
+    }
+
+    /**
+     * Returns an instance of {@code AtomicIdGenerator} with specified name.
+     *
+     * @param name ID generator name
+     * @return AtomicIdGenerator instance
+     */
+    default AtomicIdGenerator getAtomicIdGenerator(String name) {
+        return getAsyncAtomicIdGenerator(name).asAtomicIdGenerator();
+    }
+
+    /**
+     * Returns an instance of {@code WorkQueue} with specified name.
+     *
+     * @param <E> work element type
+     * @param name work queue name
+     * @param serializer serializer
+     * @return WorkQueue instance
+     */
+    <E> WorkQueue<E> getWorkQueue(String name, Serializer serializer);
+
+    /**
+     * Returns an instance of {@code AsyncDocumentTree} with specified name.
+     *
+     * @param <V> tree node value type
+     * @param name document tree name
+     * @param serializer serializer
+     * @return AsyncDocumentTree instance
+     */
+    <V> AsyncDocumentTree<V> getDocumentTree(String name, Serializer serializer);
+
+     /** Returns a set backed instance of {@code AsyncConsistentMultimap} with
+     * the specified name.
+     *
+     * @param name the multimap name
+     * @param serializer serializer
+     * @param <K> key type
+     * @param <V> value type
+     * @return set backed {@code AsyncConsistentMultimap} instance
+     */
+    <K, V> AsyncConsistentMultimap<K, V> getAsyncSetMultimap(String name,
+                                                             Serializer serializer);
+
+    /**
+     * Returns an instance of {@code AsyncConsistentTreeMap} with the specified
+     * name.
+     *
+     * @param name the treemap name
+     * @param serializer serializer
+     * @param <V> value type
+     * @return set backed {@code AsyncConsistentTreeMap} instance
+     */
+    <V> AsyncConsistentTreeMap<V> getAsyncTreeMap(String name,
+                                                  Serializer serializer);
+
+    /**
+     * Returns an instance of {@code Topic} with specified name.
+     *
+     * @param <T> topic message type
+     * @param name topic name
+     * @param serializer serializer
+     *
+     * @return Topic instance
+     */
+    <T> Topic<T> getTopic(String name, Serializer serializer);
 }
diff --git a/core/api/src/test/java/org/onosproject/store/service/StorageServiceAdapter.java b/core/api/src/test/java/org/onosproject/store/service/StorageServiceAdapter.java
index 14850ce..4d528e2 100644
--- a/core/api/src/test/java/org/onosproject/store/service/StorageServiceAdapter.java
+++ b/core/api/src/test/java/org/onosproject/store/service/StorageServiceAdapter.java
@@ -60,6 +60,11 @@
     }
 
     @Override
+    public DistributedLockBuilder lockBuilder() {
+        return null;
+    }
+
+    @Override
     public LeaderElectorBuilder leaderElectorBuilder() {
         return null;
     }
diff --git a/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/DefaultDistributedLockBuilder.java b/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/DefaultDistributedLockBuilder.java
new file mode 100644
index 0000000..fffebcc
--- /dev/null
+++ b/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/DefaultDistributedLockBuilder.java
@@ -0,0 +1,37 @@
+/*
+ * Copyright 2018-present Open Networking 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.onosproject.store.primitives.impl;
+
+import org.onosproject.store.primitives.DistributedPrimitiveCreator;
+import org.onosproject.store.service.AsyncDistributedLock;
+import org.onosproject.store.service.DistributedLockBuilder;
+
+/**
+ * Default implementation of DistributedLockBuilder.
+ */
+public class DefaultDistributedLockBuilder extends DistributedLockBuilder {
+
+    private final DistributedPrimitiveCreator primitiveCreator;
+
+    public DefaultDistributedLockBuilder(DistributedPrimitiveCreator primitiveCreator) {
+        this.primitiveCreator = primitiveCreator;
+    }
+
+    @Override
+    public AsyncDistributedLock build() {
+        return primitiveCreator.newAsyncDistributedLock(name());
+    }
+}
diff --git a/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/FederatedDistributedPrimitiveCreator.java b/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/FederatedDistributedPrimitiveCreator.java
index 04b94ff..0e53f77 100644
--- a/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/FederatedDistributedPrimitiveCreator.java
+++ b/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/FederatedDistributedPrimitiveCreator.java
@@ -40,6 +40,7 @@
 import org.onosproject.store.service.AsyncConsistentMap;
 import org.onosproject.store.service.AsyncConsistentMultimap;
 import org.onosproject.store.service.AsyncConsistentTreeMap;
+import org.onosproject.store.service.AsyncDistributedLock;
 import org.onosproject.store.service.AsyncDistributedSet;
 import org.onosproject.store.service.AsyncDocumentTree;
 import org.onosproject.store.service.AsyncLeaderElector;
@@ -130,6 +131,11 @@
     }
 
     @Override
+    public AsyncDistributedLock newAsyncDistributedLock(String name) {
+        return getCreator(name).newAsyncDistributedLock(name);
+    }
+
+    @Override
     public AsyncLeaderElector newAsyncLeaderElector(String name, long leaderTimeout, TimeUnit timeUnit) {
         checkNotNull(name);
         Map<PartitionId, AsyncLeaderElector> leaderElectors =
diff --git a/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/StorageManager.java b/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/StorageManager.java
index 2474d74..de3229f 100644
--- a/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/StorageManager.java
+++ b/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/StorageManager.java
@@ -47,6 +47,7 @@
 import org.onosproject.store.service.ConsistentMapBuilder;
 import org.onosproject.store.service.ConsistentMultimapBuilder;
 import org.onosproject.store.service.ConsistentTreeMapBuilder;
+import org.onosproject.store.service.DistributedLockBuilder;
 import org.onosproject.store.service.DistributedSetBuilder;
 import org.onosproject.store.service.DocumentTreeBuilder;
 import org.onosproject.store.service.EventuallyConsistentMapBuilder;
@@ -236,6 +237,12 @@
     }
 
     @Override
+    public DistributedLockBuilder lockBuilder() {
+        checkPermission(STORAGE_WRITE);
+        return new DefaultDistributedLockBuilder(federatedPrimitiveCreator);
+    }
+
+    @Override
     public LeaderElectorBuilder leaderElectorBuilder() {
         checkPermission(STORAGE_WRITE);
         return new DefaultLeaderElectorBuilder(federatedPrimitiveCreator);
diff --git a/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/StoragePartition.java b/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/StoragePartition.java
index 5d33e1c..9458ec5 100644
--- a/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/StoragePartition.java
+++ b/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/StoragePartition.java
@@ -40,6 +40,7 @@
 import org.onosproject.store.primitives.resources.impl.AtomixConsistentSetMultimapService;
 import org.onosproject.store.primitives.resources.impl.AtomixConsistentTreeMapService;
 import org.onosproject.store.primitives.resources.impl.AtomixCounterService;
+import org.onosproject.store.primitives.resources.impl.AtomixDistributedLockService;
 import org.onosproject.store.primitives.resources.impl.AtomixDocumentTreeService;
 import org.onosproject.store.primitives.resources.impl.AtomixLeaderElectorService;
 import org.onosproject.store.primitives.resources.impl.AtomixWorkQueueService;
@@ -78,6 +79,7 @@
                             () -> new AtomixDocumentTreeService(Ordering.NATURAL))
                     .put(String.format("%s-%s", DistributedPrimitive.Type.DOCUMENT_TREE.name(), Ordering.INSERTION),
                             () -> new AtomixDocumentTreeService(Ordering.INSERTION))
+                    .put(DistributedPrimitive.Type.LOCK.name(), AtomixDistributedLockService::new)
                     .build();
 
     public StoragePartition(
diff --git a/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/StoragePartitionClient.java b/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/StoragePartitionClient.java
index 723dc51..c5d281a 100644
--- a/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/StoragePartitionClient.java
+++ b/core/store/primitives/src/main/java/org/onosproject/store/primitives/impl/StoragePartitionClient.java
@@ -35,6 +35,7 @@
 import org.onosproject.store.primitives.resources.impl.AtomixConsistentSetMultimap;
 import org.onosproject.store.primitives.resources.impl.AtomixConsistentTreeMap;
 import org.onosproject.store.primitives.resources.impl.AtomixCounter;
+import org.onosproject.store.primitives.resources.impl.AtomixDistributedLock;
 import org.onosproject.store.primitives.resources.impl.AtomixDocumentTree;
 import org.onosproject.store.primitives.resources.impl.AtomixIdGenerator;
 import org.onosproject.store.primitives.resources.impl.AtomixLeaderElector;
@@ -47,6 +48,7 @@
 import org.onosproject.store.service.AsyncConsistentMap;
 import org.onosproject.store.service.AsyncConsistentMultimap;
 import org.onosproject.store.service.AsyncConsistentTreeMap;
+import org.onosproject.store.service.AsyncDistributedLock;
 import org.onosproject.store.service.AsyncDistributedSet;
 import org.onosproject.store.service.AsyncDocumentTree;
 import org.onosproject.store.service.AsyncLeaderElector;
@@ -260,6 +262,21 @@
     }
 
     @Override
+    public AsyncDistributedLock newAsyncDistributedLock(String name) {
+        return new AtomixDistributedLock(client.newProxyBuilder()
+                .withName(name)
+                .withServiceType(DistributedPrimitive.Type.LOCK.name())
+                .withReadConsistency(ReadConsistency.LINEARIZABLE)
+                .withCommunicationStrategy(CommunicationStrategy.LEADER)
+                .withMinTimeout(Duration.ofSeconds(1))
+                .withMaxTimeout(Duration.ofSeconds(5))
+                .withMaxRetries(MAX_RETRIES)
+                .build()
+                .open()
+                .join());
+    }
+
+    @Override
     public AsyncLeaderElector newAsyncLeaderElector(String name, long leaderTimeout, TimeUnit timeUnit) {
         AtomixLeaderElector leaderElector = new AtomixLeaderElector(client.newProxyBuilder()
                 .withName(name)
diff --git a/core/store/primitives/src/main/java/org/onosproject/store/primitives/resources/impl/AtomixDistributedLock.java b/core/store/primitives/src/main/java/org/onosproject/store/primitives/resources/impl/AtomixDistributedLock.java
new file mode 100644
index 0000000..c5a4250
--- /dev/null
+++ b/core/store/primitives/src/main/java/org/onosproject/store/primitives/resources/impl/AtomixDistributedLock.java
@@ -0,0 +1,164 @@
+/*
+ * Copyright 2018-present Open Networking 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.onosproject.store.primitives.resources.impl;
+
+import java.time.Duration;
+import java.util.Iterator;
+import java.util.Map;
+import java.util.Optional;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import io.atomix.protocols.raft.proxy.RaftProxy;
+import io.atomix.utils.concurrent.Futures;
+import org.onlab.util.KryoNamespace;
+import org.onosproject.store.serializers.KryoNamespaces;
+import org.onosproject.store.service.AsyncDistributedLock;
+import org.onosproject.store.service.Serializer;
+import org.onosproject.store.service.StorageException;
+import org.onosproject.store.service.Version;
+
+import static org.onosproject.store.primitives.resources.impl.AtomixDistributedLockOperations.LOCK;
+import static org.onosproject.store.primitives.resources.impl.AtomixDistributedLockOperations.Lock;
+import static org.onosproject.store.primitives.resources.impl.AtomixDistributedLockOperations.UNLOCK;
+import static org.onosproject.store.primitives.resources.impl.AtomixDistributedLockOperations.Unlock;
+
+/**
+ * Atomix lock implementation.
+ */
+public class AtomixDistributedLock extends AbstractRaftPrimitive implements AsyncDistributedLock {
+    private static final Serializer SERIALIZER = Serializer.using(KryoNamespace.newBuilder()
+        .register(KryoNamespaces.BASIC)
+        .register(AtomixDistributedLockOperations.NAMESPACE)
+        .register(AtomixDistributedLockEvents.NAMESPACE)
+        .build());
+
+    private final Map<Integer, CompletableFuture<Version>> futures = new ConcurrentHashMap<>();
+    private final AtomicInteger id = new AtomicInteger();
+    private int lock;
+
+    public AtomixDistributedLock(RaftProxy proxy) {
+        super(proxy);
+        proxy.addStateChangeListener(this::handleStateChange);
+        proxy.addEventListener(AtomixDistributedLockEvents.LOCK, SERIALIZER::decode, this::handleLocked);
+        proxy.addEventListener(AtomixDistributedLockEvents.FAIL, SERIALIZER::decode, this::handleFailed);
+    }
+
+    private void handleLocked(LockEvent event) {
+        CompletableFuture<Version> future = futures.remove(event.id());
+        if (future != null) {
+            this.lock = event.id();
+            future.complete(new Version(event.version()));
+        }
+    }
+
+    private void handleFailed(LockEvent event) {
+        CompletableFuture<Version> future = futures.remove(event.id());
+        if (future != null) {
+            future.complete(null);
+        }
+    }
+
+    private void handleStateChange(RaftProxy.State state) {
+        if (state != RaftProxy.State.CONNECTED) {
+            Iterator<Map.Entry<Integer, CompletableFuture<Version>>> iterator = futures.entrySet().iterator();
+            while (iterator.hasNext()) {
+                Map.Entry<Integer, CompletableFuture<Version>> entry = iterator.next();
+                entry.getValue().completeExceptionally(new StorageException.Unavailable());
+                proxy.invoke(UNLOCK, SERIALIZER::encode, new Unlock(entry.getKey()));
+                iterator.remove();
+            }
+            lock = 0;
+        }
+    }
+
+    @Override
+    public CompletableFuture<Version> lock() {
+        RaftProxy.State state = proxy.getState();
+        if (state != RaftProxy.State.CONNECTED) {
+            return Futures.exceptionalFuture(new StorageException.Unavailable());
+        }
+
+        CompletableFuture<Version> future = new CompletableFuture<>();
+        int id = this.id.incrementAndGet();
+        futures.put(id, future);
+        proxy.invoke(LOCK, SERIALIZER::encode, new Lock(id, -1)).whenComplete((result, error) -> {
+            if (error != null) {
+                futures.remove(id);
+                future.completeExceptionally(error);
+            }
+        });
+        return future;
+    }
+
+    @Override
+    public CompletableFuture<Optional<Version>> tryLock() {
+        RaftProxy.State state = proxy.getState();
+        if (state != RaftProxy.State.CONNECTED) {
+            return Futures.exceptionalFuture(new StorageException.Unavailable());
+        }
+
+        CompletableFuture<Version> future = new CompletableFuture<>();
+        int id = this.id.incrementAndGet();
+        futures.put(id, future);
+        proxy.invoke(LOCK, SERIALIZER::encode, new Lock(id, 0)).whenComplete((result, error) -> {
+            if (error != null) {
+                futures.remove(id);
+                future.completeExceptionally(error);
+            }
+        });
+        return future.thenApply(Optional::ofNullable);
+    }
+
+    @Override
+    public CompletableFuture<Optional<Version>> tryLock(Duration timeout) {
+        RaftProxy.State state = proxy.getState();
+        if (state != RaftProxy.State.CONNECTED) {
+            return Futures.exceptionalFuture(new StorageException.Unavailable());
+        }
+
+        CompletableFuture<Version> future = new CompletableFuture<>();
+        int id = this.id.incrementAndGet();
+        futures.put(id, future);
+        proxy.invoke(LOCK, SERIALIZER::encode, new Lock(id, timeout.toMillis())).whenComplete((result, error) -> {
+            if (error != null) {
+                futures.remove(id);
+                future.completeExceptionally(error);
+            }
+        });
+        return future.thenApply(Optional::ofNullable);
+    }
+
+    @Override
+    public CompletableFuture<Void> unlock() {
+        int lock = this.lock;
+        this.lock = 0;
+        if (lock != 0) {
+            return proxy.invoke(UNLOCK, SERIALIZER::encode, new Unlock(lock));
+        }
+        return CompletableFuture.completedFuture(null);
+    }
+
+    /**
+     * Closes the lock.
+     *
+     * @return a future to be completed once the lock has been closed
+     */
+    public CompletableFuture<Void> close() {
+        return proxy.close();
+    }
+}
\ No newline at end of file
diff --git a/core/store/primitives/src/main/java/org/onosproject/store/primitives/resources/impl/AtomixDistributedLockEvents.java b/core/store/primitives/src/main/java/org/onosproject/store/primitives/resources/impl/AtomixDistributedLockEvents.java
new file mode 100644
index 0000000..0ef9270
--- /dev/null
+++ b/core/store/primitives/src/main/java/org/onosproject/store/primitives/resources/impl/AtomixDistributedLockEvents.java
@@ -0,0 +1,46 @@
+/*
+ * Copyright 2018-present Open Networking 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.onosproject.store.primitives.resources.impl;
+
+import io.atomix.protocols.raft.event.EventType;
+import org.onlab.util.KryoNamespace;
+import org.onosproject.store.serializers.KryoNamespaces;
+
+/**
+ * Raft value events.
+ */
+public enum AtomixDistributedLockEvents implements EventType {
+    LOCK("lock"),
+    FAIL("fail");
+
+    private final String id;
+
+    AtomixDistributedLockEvents(String id) {
+        this.id = id;
+    }
+
+    @Override
+    public String id() {
+        return id;
+    }
+
+    public static final KryoNamespace NAMESPACE = KryoNamespace.newBuilder()
+        .nextId(KryoNamespaces.BEGIN_USER_CUSTOM_ID + 50)
+        .register(LockEvent.class)
+        .register(byte[].class)
+        .build(AtomixDistributedLockEvents.class.getSimpleName());
+
+}
diff --git a/core/store/primitives/src/main/java/org/onosproject/store/primitives/resources/impl/AtomixDistributedLockOperations.java b/core/store/primitives/src/main/java/org/onosproject/store/primitives/resources/impl/AtomixDistributedLockOperations.java
new file mode 100644
index 0000000..5cfbc84
--- /dev/null
+++ b/core/store/primitives/src/main/java/org/onosproject/store/primitives/resources/impl/AtomixDistributedLockOperations.java
@@ -0,0 +1,137 @@
+/*
+ * Copyright 2018-present Open Networking 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.onosproject.store.primitives.resources.impl;
+
+import io.atomix.protocols.raft.operation.OperationId;
+import io.atomix.protocols.raft.operation.OperationType;
+import org.onlab.util.KryoNamespace;
+import org.onosproject.store.serializers.KryoNamespaces;
+
+import static com.google.common.base.MoreObjects.toStringHelper;
+
+/**
+ * {@link org.onosproject.store.service.DistributedLock} operations.
+ * <p>
+ * WARNING: Do not refactor enum values. Only add to them.
+ * Changing values risk breaking the ability to backup/restore/upgrade clusters.
+ */
+public enum AtomixDistributedLockOperations implements OperationId {
+    LOCK(OperationType.COMMAND),
+    UNLOCK(OperationType.COMMAND);
+
+    private final OperationType type;
+
+    AtomixDistributedLockOperations(OperationType type) {
+        this.type = type;
+    }
+
+    @Override
+    public String id() {
+        return name();
+    }
+
+    @Override
+    public OperationType type() {
+        return type;
+    }
+
+    public static final KryoNamespace NAMESPACE = KryoNamespace.newBuilder()
+        .register(KryoNamespaces.BASIC)
+        .nextId(KryoNamespaces.BEGIN_USER_CUSTOM_ID)
+        .register(Lock.class)
+        .register(Unlock.class)
+        .build(AtomixDistributedLockOperations.class.getSimpleName());
+
+    /**
+     * Abstract lock operation.
+     */
+    public abstract static class LockOperation {
+        @Override
+        public String toString() {
+            return toStringHelper(this).toString();
+        }
+    }
+
+    /**
+     * Lock command.
+     */
+    public static class Lock extends LockOperation {
+        private final int id;
+        private final long timeout;
+
+        public Lock() {
+            this(0, 0);
+        }
+
+        public Lock(int id, long timeout) {
+            this.id = id;
+            this.timeout = timeout;
+        }
+
+        /**
+         * Returns the lock identifier.
+         *
+         * @return the lock identifier
+         */
+        public int id() {
+            return id;
+        }
+
+        /**
+         * Returns the lock attempt timeout.
+         *
+         * @return the lock attempt timeout
+         */
+        public long timeout() {
+            return timeout;
+        }
+
+        @Override
+        public String toString() {
+            return toStringHelper(this)
+                .add("id", id)
+                .add("timeout", timeout)
+                .toString();
+        }
+    }
+
+    /**
+     * Unlock command.
+     */
+    public static class Unlock extends LockOperation {
+        private final int id;
+
+        public Unlock(int id) {
+            this.id = id;
+        }
+
+        /**
+         * Returns the lock identifier.
+         *
+         * @return the lock identifier
+         */
+        public int id() {
+            return id;
+        }
+
+        @Override
+        public String toString() {
+            return toStringHelper(this)
+                .add("id", id)
+                .toString();
+        }
+    }
+}
\ No newline at end of file
diff --git a/core/store/primitives/src/main/java/org/onosproject/store/primitives/resources/impl/AtomixDistributedLockService.java b/core/store/primitives/src/main/java/org/onosproject/store/primitives/resources/impl/AtomixDistributedLockService.java
new file mode 100644
index 0000000..a2dab95
--- /dev/null
+++ b/core/store/primitives/src/main/java/org/onosproject/store/primitives/resources/impl/AtomixDistributedLockService.java
@@ -0,0 +1,231 @@
+/*
+ * Copyright 2018-present Open Networking 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.onosproject.store.primitives.resources.impl;
+
+import java.time.Duration;
+import java.util.ArrayDeque;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Queue;
+
+import io.atomix.protocols.raft.service.AbstractRaftService;
+import io.atomix.protocols.raft.service.Commit;
+import io.atomix.protocols.raft.service.RaftServiceExecutor;
+import io.atomix.protocols.raft.session.RaftSession;
+import io.atomix.protocols.raft.storage.snapshot.SnapshotReader;
+import io.atomix.protocols.raft.storage.snapshot.SnapshotWriter;
+import io.atomix.utils.concurrent.Scheduled;
+import org.onlab.util.KryoNamespace;
+import org.onosproject.store.serializers.KryoNamespaces;
+import org.onosproject.store.service.Serializer;
+
+import static com.google.common.base.MoreObjects.toStringHelper;
+import static org.onosproject.store.primitives.resources.impl.AtomixDistributedLockEvents.FAIL;
+import static org.onosproject.store.primitives.resources.impl.AtomixDistributedLockOperations.LOCK;
+import static org.onosproject.store.primitives.resources.impl.AtomixDistributedLockOperations.Lock;
+import static org.onosproject.store.primitives.resources.impl.AtomixDistributedLockOperations.UNLOCK;
+import static org.onosproject.store.primitives.resources.impl.AtomixDistributedLockOperations.Unlock;
+
+/**
+ * Raft atomic value service.
+ */
+public class AtomixDistributedLockService extends AbstractRaftService {
+    private static final Serializer SERIALIZER = Serializer.using(KryoNamespace.newBuilder()
+        .register(KryoNamespaces.BASIC)
+        .register(AtomixDistributedLockOperations.NAMESPACE)
+        .register(AtomixDistributedLockEvents.NAMESPACE)
+        .register(LockHolder.class)
+        .register(ArrayDeque.class)
+        .build());
+
+    private LockHolder lock;
+    private Queue<LockHolder> queue = new ArrayDeque<>();
+    private final Map<Long, Scheduled> timers = new HashMap<>();
+
+    @Override
+    protected void configure(RaftServiceExecutor executor) {
+        executor.register(LOCK, SERIALIZER::decode, this::lock);
+        executor.register(UNLOCK, SERIALIZER::decode, this::unlock);
+    }
+
+    @Override
+    public void snapshot(SnapshotWriter writer) {
+        writer.writeObject(lock, SERIALIZER::encode);
+        writer.writeObject(queue, SERIALIZER::encode);
+    }
+
+    @Override
+    public void install(SnapshotReader reader) {
+        lock = reader.readObject(SERIALIZER::decode);
+        queue = reader.readObject(SERIALIZER::decode);
+        timers.values().forEach(Scheduled::cancel);
+        timers.clear();
+        for (LockHolder holder : queue) {
+            if (holder.expire > 0) {
+                timers.put(holder.index,
+                    scheduler().schedule(Duration.ofMillis(holder.expire - wallClock().getTime().unixTimestamp()),
+                        () -> {
+                            timers.remove(holder.index);
+                            queue.remove(holder);
+                            RaftSession session = sessions().getSession(holder.session);
+                            if (session != null && session.getState().active()) {
+                                session.publish(FAIL, SERIALIZER::encode, new LockEvent(holder.id, holder.index));
+                            }
+                        }));
+            }
+        }
+    }
+
+    @Override
+    public void onExpire(RaftSession session) {
+        releaseSession(session);
+    }
+
+    @Override
+    public void onClose(RaftSession session) {
+        releaseSession(session);
+    }
+
+    /**
+     * Applies a lock commit.
+     *
+     * @param commit the lock commit
+     */
+    protected void lock(Commit<Lock> commit) {
+        if (lock == null) {
+            lock = new LockHolder(
+                commit.value().id(),
+                commit.index(),
+                commit.session().sessionId().id(),
+                0);
+            commit.session().publish(
+                AtomixDistributedLockEvents.LOCK,
+                SERIALIZER::encode,
+                new LockEvent(commit.value().id(), commit.index()));
+        } else if (commit.value().timeout() == 0) {
+            commit.session().publish(FAIL, SERIALIZER::encode, new LockEvent(commit.value().id(), commit.index()));
+        } else if (commit.value().timeout() > 0) {
+            LockHolder holder = new LockHolder(
+                commit.value().id(),
+                commit.index(),
+                commit.session().sessionId().id(),
+                wallClock().getTime().unixTimestamp() + commit.value().timeout());
+            queue.add(holder);
+            timers.put(commit.index(), scheduler().schedule(Duration.ofMillis(commit.value().timeout()), () -> {
+                timers.remove(commit.index());
+                queue.remove(holder);
+                if (commit.session().getState().active()) {
+                    commit.session().publish(
+                        FAIL,
+                        SERIALIZER::encode,
+                        new LockEvent(commit.value().id(), commit.index()));
+                }
+            }));
+        } else {
+            LockHolder holder = new LockHolder(
+                commit.value().id(),
+                commit.index(),
+                commit.session().sessionId().id(),
+                0);
+            queue.add(holder);
+        }
+    }
+
+    /**
+     * Applies an unlock commit.
+     *
+     * @param commit the unlock commit
+     */
+    protected void unlock(Commit<Unlock> commit) {
+        if (lock != null) {
+            if (lock.session != commit.session().sessionId().id()) {
+                return;
+            }
+
+            lock = queue.poll();
+            while (lock != null) {
+                Scheduled timer = timers.remove(lock.index);
+                if (timer != null) {
+                    timer.cancel();
+                }
+
+                RaftSession session = sessions().getSession(lock.session);
+                if (session == null || session.getState() == RaftSession.State.EXPIRED
+                    || session.getState() == RaftSession.State.CLOSED) {
+                    lock = queue.poll();
+                } else {
+                    session.publish(
+                        AtomixDistributedLockEvents.LOCK,
+                        SERIALIZER::encode,
+                        new LockEvent(lock.id, commit.index()));
+                    break;
+                }
+            }
+        }
+    }
+
+    private void releaseSession(RaftSession session) {
+        if (lock != null && lock.session == session.sessionId().id()) {
+            lock = queue.poll();
+            while (lock != null) {
+                if (lock.session == session.sessionId().id()) {
+                    lock = queue.poll();
+                } else {
+                    Scheduled timer = timers.remove(lock.index);
+                    if (timer != null) {
+                        timer.cancel();
+                    }
+
+                    RaftSession lockSession = sessions().getSession(lock.session);
+                    if (lockSession == null || lockSession.getState() == RaftSession.State.EXPIRED
+                        || lockSession.getState() == RaftSession.State.CLOSED) {
+                        lock = queue.poll();
+                    } else {
+                        lockSession.publish(
+                            AtomixDistributedLockEvents.LOCK,
+                            SERIALIZER::encode,
+                            new LockEvent(lock.id, lock.index));
+                        break;
+                    }
+                }
+            }
+        }
+    }
+
+    private class LockHolder {
+        private final int id;
+        private final long index;
+        private final long session;
+        private final long expire;
+
+        public LockHolder(int id, long index, long session, long expire) {
+            this.id = id;
+            this.index = index;
+            this.session = session;
+            this.expire = expire;
+        }
+
+        @Override
+        public String toString() {
+            return toStringHelper(this)
+                .add("id", id)
+                .add("index", index)
+                .add("session", session)
+                .add("expire", expire)
+                .toString();
+        }
+    }
+}
\ No newline at end of file
diff --git a/core/store/primitives/src/main/java/org/onosproject/store/primitives/resources/impl/LockEvent.java b/core/store/primitives/src/main/java/org/onosproject/store/primitives/resources/impl/LockEvent.java
new file mode 100644
index 0000000..cddb41f
--- /dev/null
+++ b/core/store/primitives/src/main/java/org/onosproject/store/primitives/resources/impl/LockEvent.java
@@ -0,0 +1,61 @@
+/*
+ * Copyright 2018-present Open Networking 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.onosproject.store.primitives.resources.impl;
+
+import static com.google.common.base.MoreObjects.toStringHelper;
+
+/**
+ * Locked event.
+ */
+public class LockEvent {
+  private final int id;
+  private final long version;
+
+  public LockEvent() {
+    this(0, 0);
+  }
+
+  public LockEvent(int id, long version) {
+    this.id = id;
+    this.version = version;
+  }
+
+  /**
+   * Returns the lock ID.
+   *
+   * @return The lock ID.
+   */
+  public int id() {
+    return id;
+  }
+
+  /**
+   * Returns the lock version.
+   *
+   * @return The lock version.
+   */
+  public long version() {
+    return version;
+  }
+
+  @Override
+  public String toString() {
+    return toStringHelper(this)
+        .add("id", id)
+        .add("version", version)
+        .toString();
+  }
+}
diff --git a/core/store/primitives/src/test/java/org/onosproject/store/primitives/resources/impl/AtomixDistributedLockServiceTest.java b/core/store/primitives/src/test/java/org/onosproject/store/primitives/resources/impl/AtomixDistributedLockServiceTest.java
new file mode 100644
index 0000000..69942a7
--- /dev/null
+++ b/core/store/primitives/src/test/java/org/onosproject/store/primitives/resources/impl/AtomixDistributedLockServiceTest.java
@@ -0,0 +1,116 @@
+/*
+ * Copyright 2018-present Open Networking 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.onosproject.store.primitives.resources.impl;
+
+import java.util.concurrent.atomic.AtomicLong;
+
+import io.atomix.protocols.raft.ReadConsistency;
+import io.atomix.protocols.raft.cluster.MemberId;
+import io.atomix.protocols.raft.impl.RaftContext;
+import io.atomix.protocols.raft.operation.OperationType;
+import io.atomix.protocols.raft.protocol.RaftServerProtocol;
+import io.atomix.protocols.raft.service.ServiceId;
+import io.atomix.protocols.raft.service.ServiceType;
+import io.atomix.protocols.raft.service.impl.DefaultCommit;
+import io.atomix.protocols.raft.service.impl.DefaultServiceContext;
+import io.atomix.protocols.raft.session.SessionId;
+import io.atomix.protocols.raft.session.impl.RaftSessionContext;
+import io.atomix.protocols.raft.storage.RaftStorage;
+import io.atomix.protocols.raft.storage.snapshot.Snapshot;
+import io.atomix.protocols.raft.storage.snapshot.SnapshotReader;
+import io.atomix.protocols.raft.storage.snapshot.SnapshotStore;
+import io.atomix.protocols.raft.storage.snapshot.SnapshotWriter;
+import io.atomix.storage.StorageLevel;
+import io.atomix.time.WallClockTimestamp;
+import io.atomix.utils.concurrent.AtomixThreadFactory;
+import io.atomix.utils.concurrent.SingleThreadContextFactory;
+import io.atomix.utils.concurrent.ThreadContext;
+import org.junit.Test;
+
+import static org.easymock.EasyMock.expect;
+import static org.easymock.EasyMock.mock;
+import static org.easymock.EasyMock.replay;
+import static org.onosproject.store.service.DistributedPrimitive.Type.LEADER_ELECTOR;
+
+/**
+ * Distributed lock service test.
+ */
+public class AtomixDistributedLockServiceTest {
+    @Test
+    public void testSnapshot() throws Exception {
+        SnapshotStore store = new SnapshotStore(RaftStorage.newBuilder()
+            .withPrefix("test")
+            .withStorageLevel(StorageLevel.MEMORY)
+            .build());
+        Snapshot snapshot = store.newSnapshot(ServiceId.from(1), "test", 2, new WallClockTimestamp());
+
+        AtomicLong index = new AtomicLong();
+        DefaultServiceContext context = mock(DefaultServiceContext.class);
+        expect(context.serviceType()).andReturn(ServiceType.from(LEADER_ELECTOR.name())).anyTimes();
+        expect(context.serviceName()).andReturn("test").anyTimes();
+        expect(context.serviceId()).andReturn(ServiceId.from(1)).anyTimes();
+        expect(context.executor()).andReturn(mock(ThreadContext.class)).anyTimes();
+        expect(context.currentIndex()).andReturn(index.get()).anyTimes();
+        expect(context.currentOperation()).andReturn(OperationType.COMMAND).anyTimes();
+
+        RaftContext server = mock(RaftContext.class);
+        expect(server.getProtocol()).andReturn(mock(RaftServerProtocol.class));
+
+        replay(context, server);
+
+        AtomixDistributedLockService service = new AtomixDistributedLockService();
+        service.init(context);
+
+        RaftSessionContext session = new RaftSessionContext(
+            SessionId.from(1),
+            MemberId.from("1"),
+            "test",
+            ServiceType.from(LEADER_ELECTOR.name()),
+            ReadConsistency.LINEARIZABLE,
+            100,
+            5000,
+            System.currentTimeMillis(),
+            context,
+            server,
+            new SingleThreadContextFactory(new AtomixThreadFactory()));
+        session.open();
+
+        service.lock(new DefaultCommit<>(
+            index.incrementAndGet(),
+            AtomixDistributedLockOperations.LOCK,
+            new AtomixDistributedLockOperations.Lock(1, 0),
+            session,
+            System.currentTimeMillis()));
+
+        try (SnapshotWriter writer = snapshot.openWriter()) {
+            service.snapshot(writer);
+        }
+
+        snapshot.complete();
+
+        service = new AtomixDistributedLockService();
+        try (SnapshotReader reader = snapshot.openReader()) {
+            service.install(reader);
+        }
+
+        service.unlock(new DefaultCommit<>(
+            index.incrementAndGet(),
+            AtomixDistributedLockOperations.UNLOCK,
+            new AtomixDistributedLockOperations.Unlock(1),
+            session,
+            System.currentTimeMillis()));
+    }
+}
diff --git a/core/store/primitives/src/test/java/org/onosproject/store/primitives/resources/impl/AtomixDistributedLockTest.java b/core/store/primitives/src/test/java/org/onosproject/store/primitives/resources/impl/AtomixDistributedLockTest.java
new file mode 100644
index 0000000..cc32ba9
--- /dev/null
+++ b/core/store/primitives/src/test/java/org/onosproject/store/primitives/resources/impl/AtomixDistributedLockTest.java
@@ -0,0 +1,131 @@
+/*
+ * Copyright 2018-present Open Networking 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.onosproject.store.primitives.resources.impl;
+
+import java.time.Duration;
+import java.util.Optional;
+import java.util.concurrent.CompletableFuture;
+
+import io.atomix.protocols.raft.proxy.RaftProxy;
+import io.atomix.protocols.raft.service.RaftService;
+import org.junit.Test;
+import org.onosproject.store.service.Version;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+/**
+ * Raft lock test.
+ */
+public class AtomixDistributedLockTest extends AtomixTestBase<AtomixDistributedLock> {
+    @Override
+    protected RaftService createService() {
+        return new AtomixDistributedLockService();
+    }
+
+    @Override
+    protected AtomixDistributedLock createPrimitive(RaftProxy proxy) {
+        return new AtomixDistributedLock(proxy);
+    }
+
+    /**
+     * Tests locking and unlocking a lock.
+     */
+    @Test
+    public void testLockUnlock() throws Throwable {
+        AtomixDistributedLock lock = newPrimitive("test-lock-unlock");
+        lock.lock().join();
+        lock.unlock().join();
+    }
+
+    /**
+     * Tests releasing a lock when the client's session is closed.
+     */
+    @Test
+    public void testReleaseOnClose() throws Throwable {
+        AtomixDistributedLock lock1 = newPrimitive("test-lock-release-on-close");
+        AtomixDistributedLock lock2 = newPrimitive("test-lock-release-on-close");
+        lock1.lock().join();
+        CompletableFuture<Version> future = lock2.lock();
+        lock1.close();
+        future.join();
+    }
+
+    /**
+     * Tests attempting to acquire a lock.
+     */
+    @Test
+    public void testTryLockFail() throws Throwable {
+        AtomixDistributedLock lock1 = newPrimitive("test-try-lock-fail");
+        AtomixDistributedLock lock2 = newPrimitive("test-try-lock-fail");
+
+        lock1.lock().join();
+
+        assertFalse(lock2.tryLock().join().isPresent());
+    }
+
+    /**
+     * Tests attempting to acquire a lock.
+     */
+    @Test
+    public void testTryLockSucceed() throws Throwable {
+        AtomixDistributedLock lock = newPrimitive("test-try-lock-succeed");
+        assertTrue(lock.tryLock().join().isPresent());
+    }
+
+    /**
+     * Tests attempting to acquire a lock with a timeout.
+     */
+    @Test
+    public void testTryLockFailWithTimeout() throws Throwable {
+        AtomixDistributedLock lock1 = newPrimitive("test-try-lock-fail-with-timeout");
+        AtomixDistributedLock lock2 = newPrimitive("test-try-lock-fail-with-timeout");
+
+        lock1.lock().join();
+
+        assertFalse(lock2.tryLock(Duration.ofSeconds(1)).join().isPresent());
+    }
+
+    /**
+     * Tests attempting to acquire a lock with a timeout.
+     */
+    @Test
+    public void testTryLockSucceedWithTimeout() throws Throwable {
+        AtomixDistributedLock lock1 = newPrimitive("test-try-lock-succeed-with-timeout");
+        AtomixDistributedLock lock2 = newPrimitive("test-try-lock-succeed-with-timeout");
+
+        lock1.lock().join();
+
+        CompletableFuture<Optional<Version>> future = lock2.tryLock(Duration.ofSeconds(1));
+        lock1.unlock().join();
+        assertTrue(future.join().isPresent());
+    }
+
+    /**
+     * Tests unlocking a lock with a blocking call in the event thread.
+     */
+    @Test
+    public void testBlockingUnlock() throws Throwable {
+        AtomixDistributedLock lock1 = newPrimitive("test-blocking-unlock");
+        AtomixDistributedLock lock2 = newPrimitive("test-blocking-unlock");
+
+        lock1.lock().thenRun(() -> {
+            lock1.unlock().join();
+        }).join();
+
+        lock2.lock().join();
+    }
+}
diff --git a/protocols/pcep/server/ctl/src/test/java/org/onosproject/pcelabelstore/util/StorageServiceAdapter.java b/protocols/pcep/server/ctl/src/test/java/org/onosproject/pcelabelstore/util/StorageServiceAdapter.java
index 2f97c7d..4ba8a2c 100644
--- a/protocols/pcep/server/ctl/src/test/java/org/onosproject/pcelabelstore/util/StorageServiceAdapter.java
+++ b/protocols/pcep/server/ctl/src/test/java/org/onosproject/pcelabelstore/util/StorageServiceAdapter.java
@@ -25,6 +25,7 @@
 import org.onosproject.store.service.ConsistentMapBuilder;
 import org.onosproject.store.service.ConsistentMultimapBuilder;
 import org.onosproject.store.service.ConsistentTreeMapBuilder;
+import org.onosproject.store.service.DistributedLockBuilder;
 import org.onosproject.store.service.DistributedSetBuilder;
 import org.onosproject.store.service.DocumentTreeBuilder;
 import org.onosproject.store.service.EventuallyConsistentMapBuilder;
@@ -80,6 +81,11 @@
     }
 
     @Override
+    public DistributedLockBuilder lockBuilder() {
+        return null;
+    }
+
+    @Override
     public LeaderElectorBuilder leaderElectorBuilder() {
         return null;
     }