Add basic level policy support to Ditto Java Client

.github/workflows/maven.yml

@@ -23,7 +23,7 @@ jobs:
         java: [ '1.8' ]
 
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v2
     - name: set up JDK ${{ matrix.java }}
       uses: actions/setup-java@v1
       with:

.github/workflows/nodejs.yml

@@ -24,7 +24,7 @@ jobs:
         node-version: [10.x, 12.x]
 
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v2
     - name: Use Node.js ${{ matrix.node-version }}
       uses: actions/setup-node@v1
       with:

java/README.md

@@ -98,6 +98,19 @@ client.twin().create("org.eclipse.ditto:new-thing").handle((createdThing, throwa
 }).get(); // this will block the thread! work asynchronously whenever possible!
 ```
 
+#### Manage policies
+
+```java
+        client.policies().create(newPolicy)
+                .thenAccept(createdPolicy -> System.out.println("Created new Policy: " + createdPolicy)).get();
+
+        client.twin()
+                .forId(ThingId.of("org.eclipse.ditto:new-thing"))
+                .setPolicyId(newPolicy.getEntityId().get())
+                .thenAccept(_void -> System.out.println("PolicyId was adapted"))
+                .get();
+```
+
 #### Subscribe for change notifications
 
 ```java

java/src/main/assembly/assembly.xml

@@ -41,6 +41,7 @@
                 <include>org.eclipse.ditto:ditto-signals-base</include>
                 <include>org.eclipse.ditto:ditto-signals-commands-base</include>
                 <include>org.eclipse.ditto:ditto-signals-commands-things</include>
+                <include>org.eclipse.ditto:ditto-signals-commands-policies</include>
                 <include>org.eclipse.ditto:ditto-signals-commands-messages</include>
                 <include>org.eclipse.ditto:ditto-signals-commands-live</include>
                 <include>org.eclipse.ditto:ditto-signals-events-base</include>

java/src/main/java/org/eclipse/ditto/client/DittoClient.java

@@ -15,6 +15,7 @@
 import java.util.concurrent.CompletableFuture;
 
 import org.eclipse.ditto.client.live.Live;
+import org.eclipse.ditto.client.policies.Policies;
 import org.eclipse.ditto.client.twin.Twin;
 import org.eclipse.ditto.protocoladapter.Adaptable;
 
@@ -56,4 +57,12 @@ public interface DittoClient {
      */
     CompletableFuture<Adaptable> sendDittoProtocol(Adaptable dittoProtocolAdaptable);
 
+    /**
+     * Returns the client's {@link Policies} singleton which provides the necessary functionality to manage and monitor
+     * {@link org.eclipse.ditto.model.policies.Policy}s.
+     *
+     * @return the Policy handle
+     * @since 1.1.0
+     */
+    Policies policies();
 }

java/src/main/java/org/eclipse/ditto/client/DittoClients.java

@@ -66,11 +66,28 @@ public static DittoClient newInstance(final MessagingProvider messagingProvider)
     public static DittoClient newInstance(final MessagingProvider twinMessagingProvider,
             final MessagingProvider liveMessagingProvider) {
 
-        final ResponseForwarder responseForwarder = ResponseForwarder.getInstance();
+        return newInstance(twinMessagingProvider, liveMessagingProvider, twinMessagingProvider);
+    }
+
+    /**
+     * Creates a new {@link org.eclipse.ditto.client.DittoClient} with a specific {@code Twin} and {@code Live}
+     * {@link org.eclipse.ditto.client.messaging.MessagingProvider}.
+     *
+     * @param twinMessagingProvider the messaging provider for the {@code Twin} part of the client.
+     * @param liveMessagingProvider the messaging provider for the {@code Live} part of the client.
+     * @param policyMessagingProvider the messaging provider for the {@code Policy} part of the client.
+     * @return the client.
+     * @throws org.eclipse.ditto.client.messaging.AuthenticationException if authentication failed.
+     * @throws org.eclipse.ditto.client.messaging.MessagingException if a connection to the configured endpoint
+     * could not be established
+     * @since 1.1.0
+     */
+    public static DittoClient newInstance(final MessagingProvider twinMessagingProvider,
+            final MessagingProvider liveMessagingProvider, final MessagingProvider policyMessagingProvider) {
+
         final MessageSerializerRegistry messageSerializerRegistry =
                 MessageSerializerFactory.newInstance().getMessageSerializerRegistry();
-        return DefaultDittoClient.newInstance(twinMessagingProvider, liveMessagingProvider, responseForwarder,
-                messageSerializerRegistry);
+        return newInstance(twinMessagingProvider, liveMessagingProvider, policyMessagingProvider, messageSerializerRegistry);
     }
 
     /**
@@ -88,9 +105,30 @@ public static DittoClient newInstance(final MessagingProvider twinMessagingProvi
     public static DittoClient newInstance(final MessagingProvider twinMessagingProvider,
             final MessagingProvider liveMessagingProvider, final MessageSerializerRegistry messageSerializerRegistry) {
 
+        return newInstance(twinMessagingProvider, liveMessagingProvider, twinMessagingProvider, messageSerializerRegistry);
+    }
+
+    /**
+     * Creates a new {@link org.eclipse.ditto.client.DittoClient} with a specific {@code Twin}, {@code Live} and
+     * {@code Policy} {@link org.eclipse.ditto.client.messaging.MessagingProvider}.
+     *
+     * @param twinMessagingProvider the messaging provider for the {@code Twin} part of the client.
+     * @param liveMessagingProvider the messaging provider for the {@code Live} part of the client.
+     * @param policyMessagingProvider the messaging provider for the {@code Policy} part of the client.
+     * @param messageSerializerRegistry a registry of {@code MessageSerializer}s for the {@code Live} part of the client.
+     * @return the client.
+     * @throws org.eclipse.ditto.client.messaging.AuthenticationException if authentication failed.
+     * @throws org.eclipse.ditto.client.messaging.MessagingException if a connection to the configured endpoint
+     * could not be established
+     * @since 1.1.0
+     */
+    public static DittoClient newInstance(final MessagingProvider twinMessagingProvider,
+            final MessagingProvider liveMessagingProvider, final MessagingProvider policyMessagingProvider,
+            final MessageSerializerRegistry messageSerializerRegistry) {
+
         final ResponseForwarder responseForwarder = ResponseForwarder.getInstance();
-        return DefaultDittoClient.newInstance(twinMessagingProvider, liveMessagingProvider, responseForwarder,
-                messageSerializerRegistry);
+        return DefaultDittoClient.newInstance(twinMessagingProvider, liveMessagingProvider, policyMessagingProvider,
+                responseForwarder, messageSerializerRegistry);
     }
 
 }

java/src/main/java/org/eclipse/ditto/client/configuration/WebSocketMessagingConfiguration.java

@@ -87,7 +87,7 @@ private static final class WebSocketMessagingConfigurationBuilder implements Mes
         private boolean reconnectEnabled = true;
         private ProxyConfiguration proxyConfiguration;
         private TrustStoreConfiguration trustStoreConfiguration;
-        
+
         @Override
         public MessagingConfiguration.Builder jsonSchemaVersion(final JsonSchemaVersion jsonSchemaVersion) {
             this.jsonSchemaVersion = checkNotNull(jsonSchemaVersion, "jsonSchemaVersion");