Adding metadata endpoint

sdk/src/main/java/io/dapr/client/DaprClient.java

@@ -14,6 +14,7 @@
 package io.dapr.client;
 
 import io.dapr.client.domain.ConfigurationItem;
+import io.dapr.client.domain.DaprMetadata;
 import io.dapr.client.domain.DeleteStateRequest;
 import io.dapr.client.domain.ExecuteStateTransactionRequest;
 import io.dapr.client.domain.GetBulkSecretRequest;
@@ -671,6 +672,13 @@ Flux<SubscribeConfigurationResponse> subscribeConfiguration(String storeName, Li
    */
   <T extends AbstractStub<T>> T newGrpcStub(String appId, Function<Channel, T> stubBuilder);
 
+  /**
+   * Fetches Dapr Metadata from the metadata endpoint.
+   *
+   * @return DaprMetadata containing Dapr Metadata from the metadata endpoint.
+   */
+  Mono<DaprMetadata> getMetadata();
+
   /**
    * Gracefully shutdown the dapr runtime.
    *

sdk/src/main/java/io/dapr/client/DaprClientImpl.java

@@ -20,7 +20,9 @@
 import io.dapr.client.domain.BulkPublishRequest;
 import io.dapr.client.domain.BulkPublishResponse;
 import io.dapr.client.domain.BulkPublishResponseFailedEntry;
+import io.dapr.client.domain.ComponentMetadata;
 import io.dapr.client.domain.ConfigurationItem;
+import io.dapr.client.domain.DaprMetadata;
 import io.dapr.client.domain.DeleteStateRequest;
 import io.dapr.client.domain.ExecuteStateTransactionRequest;
 import io.dapr.client.domain.GetBulkSecretRequest;
@@ -36,11 +38,13 @@
 import io.dapr.client.domain.QueryStateItem;
 import io.dapr.client.domain.QueryStateRequest;
 import io.dapr.client.domain.QueryStateResponse;
+import io.dapr.client.domain.RuleMetadata;
 import io.dapr.client.domain.SaveStateRequest;
 import io.dapr.client.domain.State;
 import io.dapr.client.domain.StateOptions;
 import io.dapr.client.domain.SubscribeConfigurationRequest;
 import io.dapr.client.domain.SubscribeConfigurationResponse;
+import io.dapr.client.domain.SubscriptionMetadata;
 import io.dapr.client.domain.TransactionalStateOperation;
 import io.dapr.client.domain.UnlockRequest;
 import io.dapr.client.domain.UnlockResponseStatus;
@@ -58,6 +62,10 @@
 import io.dapr.v1.CommonProtos;
 import io.dapr.v1.DaprGrpc;
 import io.dapr.v1.DaprProtos;
+import io.dapr.v1.DaprProtos.PubsubSubscription;
+import io.dapr.v1.DaprProtos.PubsubSubscriptionRule;
+import io.dapr.v1.DaprProtos.RegisteredComponents;
+import io.grpc.CallOptions;
 import io.grpc.Channel;
 import io.grpc.stub.AbstractStub;
 import io.grpc.stub.StreamObserver;
@@ -118,7 +126,8 @@ public class DaprClientImpl extends AbstractDaprClient {
   private final DaprHttp httpClient;
 
   /**
-   * Default access level constructor, in order to create an instance of this class use io.dapr.client.DaprClientBuilder
+   * Default access level constructor, in order to create an instance of this 
+   * class use io.dapr.client.DaprClientBuilder
    *
    * @param channel           Facade for the managed GRPC channel
    * @param asyncStub         async gRPC stub
@@ -1169,8 +1178,7 @@ private ConfigurationItem buildConfigurationItem(
         key,
         configurationItem.getValue(),
         configurationItem.getVersion(),
-        configurationItem.getMetadataMap()
-    );
+        configurationItem.getMetadataMap());
   }
 
   /**
@@ -1231,4 +1239,43 @@ public void onCompleted() {
       }
     };
   }
-}
+
+  @Override
+  public Mono<DaprMetadata> getMetadata() {
+    DaprProtos.GetMetadataRequest metadataRequest = DaprProtos.GetMetadataRequest.newBuilder().build();
+    return Mono.deferContextual(
+        context -> this.<DaprProtos.GetMetadataResponse>createMono(
+            it -> intercept(context, asyncStub).getMetadata(metadataRequest, it)))
+        .map(
+            it -> {
+              try {
+                return buildDaprMetadata(it);
+              } catch (IOException ex) {
+                throw DaprException.propagate(ex);
+              }
+            });
+  }
+
+  private DaprMetadata buildDaprMetadata(
+      DaprProtos.GetMetadataResponse response) throws IOException {
+    List<RegisteredComponents> registeredComponentsList = response.getRegisteredComponentsList();
+
+    List<ComponentMetadata> components = new ArrayList<>();
+    for (RegisteredComponents rc : registeredComponentsList) {
+      components.add(new ComponentMetadata(rc.getName(), rc.getType(), rc.getVersion()));
+    }
+
+    List<PubsubSubscription> subscriptionsList = response.getSubscriptionsList();
+    List<SubscriptionMetadata> subscriptions = new ArrayList<>();
+    for (PubsubSubscription s : subscriptionsList) {
+      List<PubsubSubscriptionRule> rulesList = s.getRules().getRulesList();
+      List<RuleMetadata> rules = new ArrayList<>();
+      for (PubsubSubscriptionRule r : rulesList) {
+        rules.add(new RuleMetadata(r.getPath()));
+      }
+      subscriptions.add(new SubscriptionMetadata(s.getTopic(), s.getPubsubName(), s.getDeadLetterTopic(), rules));
+    }
+
+    return new DaprMetadata(response.getId(), response.getRuntimeVersion(), components, subscriptions);
+  }
+}

sdk/src/main/java/io/dapr/client/domain/ComponentMetadata.java

@@ -0,0 +1,52 @@
+/*
+ * Copyright 2024 The Dapr Authors
+ * 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.dapr.client.domain;
+
+import java.util.Objects;
+
+/**
+ * ComponentMetadata describes a Dapr Component.
+ */
+public final class ComponentMetadata {
+
+  private String name;
+  private String type;
+  private String version;
+
+  /**
+   * Constructor for a ComponentMetadata.
+   *
+   * @param name of the component
+   * @param type component type
+   * @param version version of the component
+   */
+  public ComponentMetadata(String name, String type, String version) {
+    this.name = name;
+    this.type = type;
+    this.version = version;
+  }
+
+  public String getName() {
+    return name;
+  }
+
+  public String getType() {
+    return type;
+  }
+
+  public String getVersion() {
+    return version;
+  }
+
+}

sdk/src/main/java/io/dapr/client/domain/DaprMetadata.java

@@ -0,0 +1,62 @@
+/*
+ * Copyright 2024 The Dapr Authors
+ * 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.dapr.client.domain;
+
+import java.util.Collections;
+import java.util.List;
+import java.util.Objects;
+
+/**
+ * DaprMetadata describes the Dapr Metadata.
+ */
+public final class DaprMetadata {
+
+  private String id;
+  private String runtimeVersion;
+  private List<ComponentMetadata> components;
+  private List<SubscriptionMetadata> subscriptions;
+
+  /**
+   * Constructor for a DaprMetadata.
+   *
+   * @param id of the application
+   * @param runtimeVersion Dapr version
+   * @param components list of registered componnets
+   * @param subscriptions list of registered subscription
+   */
+  public DaprMetadata(String id, String runtimeVersion, List<ComponentMetadata> components,
+      List<SubscriptionMetadata> subscriptions) {
+    this.id = id;
+    this.runtimeVersion = runtimeVersion;
+    this.components = components == null ? Collections.emptyList() : Collections.unmodifiableList(components);
+    this.subscriptions = subscriptions == null ? Collections.emptyList() : Collections.unmodifiableList(subscriptions);
+  }
+
+  public String getId() {
+    return id;
+  }
+
+  public String getRuntimeVersion() {
+    return runtimeVersion;
+  }
+
+  public List<ComponentMetadata> getComponents() {
+    return components;
+  }
+
+  public List<SubscriptionMetadata> getSubscriptions() {
+    return subscriptions;
+  }
+
+}

sdk/src/main/java/io/dapr/client/domain/RuleMetadata.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright 2024 The Dapr Authors
+ * 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.dapr.client.domain;
+
+/**
+ * RuleMetadata describes the Subscription Rule's Metadata.
+ */
+public final class RuleMetadata {
+  private String path;
+
+  public RuleMetadata(String path) {
+    this.path = path;
+  }
+
+  public String getPath() {
+    return path;
+  }
+
+}

sdk/src/main/java/io/dapr/client/domain/SubscriptionMetadata.java

@@ -0,0 +1,62 @@
+/*
+ * Copyright 2024 The Dapr Authors
+ * 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.dapr.client.domain;
+
+import java.util.Collections;
+import java.util.List;
+import java.util.Objects;
+
+/**
+ * SubscriptionMetadata describes the Subscription Metadata.
+ */
+public final class SubscriptionMetadata {
+  private String topic;
+  private String pubsubname;
+  private String deadLetterTopic;
+  private List<RuleMetadata> rules;
+
+  /**
+   * Constructor for a SubscriptionMetadata.
+   *
+   * @param topic of the pubsub component
+   * @param pubsubname component name
+   * @param deadLetterTopic dead letter topic  
+   * @param rules subscription path rules
+   */
+  public SubscriptionMetadata(String topic, String pubsubname, String deadLetterTopic, List<RuleMetadata> rules) {
+    this.topic = topic;
+    this.pubsubname = pubsubname;
+    this.deadLetterTopic = deadLetterTopic;
+    this.rules = rules == null ? Collections.emptyList() : Collections.unmodifiableList(rules);
+  }
+
+  public String getTopic() {
+    return topic;
+  }
+
+  public String getPubsubname() {
+    return pubsubname;
+  }
+
+
+  public String getDeadLetterTopic() {
+    return deadLetterTopic;
+  }
+
+
+  public List<RuleMetadata> getRules() {
+    return rules;
+  }
+
+}