Add supoort for DAPR_API_TOKEN

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

@@ -5,6 +5,7 @@
 
 package io.dapr.client;
 
+import io.dapr.DaprClientGrpcInterceptor;
 import io.dapr.serializer.DaprObjectSerializer;
 import io.dapr.serializer.DefaultObjectSerializer;
 import io.dapr.utils.Constants;
@@ -107,7 +108,10 @@ public class DaprClientBuilder {
     if (port <= 0) {
       throw new IllegalStateException("Invalid port.");
     }
-    ManagedChannel channel = ManagedChannelBuilder.forAddress(Constants.DEFAULT_HOSTNAME, port).usePlaintext().build();
+    ManagedChannel channel = ManagedChannelBuilder.forAddress(Constants.DEFAULT_HOSTNAME, port)
+                                .usePlaintext()
+                                .intercept(new DaprClientGrpcInterceptor())
+                                .build();
     Closeable closeableChannel = () -> {
       if (channel != null && !channel.isShutdown()) {
         channel.shutdown();

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

@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) Microsoft Corporation.
+ * Licensed under the MIT License.
+ */
+
+package io.dapr;
+
+import io.dapr.utils.Constants;
+import io.dapr.utils.Properties;
+import io.grpc.CallOptions;
+import io.grpc.Channel;
+import io.grpc.ClientCall;
+import io.grpc.ClientInterceptor;
+import io.grpc.ForwardingClientCall;
+import io.grpc.Metadata;
+import io.grpc.Metadata.Key;
+import io.grpc.MethodDescriptor;
+
+/**
+ * A dapr grpc client call interceptor.
+ */
+public class DaprClientGrpcInterceptor implements ClientInterceptor {
+  
+  /**
+   * {@inheritDoc}
+   */
+  @Override
+  public <ReqT, RespT> ClientCall<ReqT, RespT> interceptCall(MethodDescriptor<ReqT,
+                                                            RespT> methodDescriptor,
+                                                            CallOptions callOptions, Channel channel) {
+    return new ForwardingClientCall.SimpleForwardingClientCall<ReqT, RespT>(channel.newCall(methodDescriptor, 
+                                                                                            callOptions)) {
+        @Override
+        public void start(final Listener<RespT> responseListener, final Metadata headers) {
+            String daprApiToken = Properties.getStringOrDefault(Constants.DAPR_API_TOKEN,
+                                                                Constants.DAPR_API_TOKEN, null);
+        if (daprApiToken != null) {
+            headers.put(Key.of(Constants.DAPR_API_TOKEN_HEADER, Metadata.ASCII_STRING_MARSHALLER), daprApiToken);
+        }
+        super.start(responseListener, headers);
+        }
+      };
+  }
+}

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

@@ -9,6 +9,7 @@ import com.fasterxml.jackson.databind.ObjectMapper;
 import io.dapr.exceptions.DaprError;
 import io.dapr.exceptions.DaprException;
 import io.dapr.utils.Constants;
+import io.dapr.utils.Properties;
 import io.grpc.Context;
 import io.opentelemetry.OpenTelemetry;
 import io.opentelemetry.context.propagation.HttpTextFormat;
@@ -258,6 +259,12 @@ public class DaprHttp implements Closeable {
     } else {
       requestBuilder.method(method, body);
     }
+
+    String daprApiToken = Properties.getStringOrDefault(Constants.DAPR_API_TOKEN, Constants.DAPR_API_TOKEN, null);
+    if (daprApiToken != null) {
+      requestBuilder.addHeader(Constants.DAPR_API_TOKEN_HEADER, daprApiToken);
+    }
+
     if (headers != null) {
       Optional.ofNullable(headers.entrySet()).orElse(Collections.emptySet()).stream()
           .forEach(header -> {

sdk/src/main/java/io/dapr/utils/Constants.java

@@ -60,6 +60,16 @@ public final class Constants {
    */
   public static final String ACTOR_TIMER_RELATIVE_URL_FORMAT = ACTORS_BASE_URL + "/%s/%s/timers/%s";
 
+  /**
+   * Environment variable name for dapr api token.
+   */
+  public static final String DAPR_API_TOKEN = "DAPR_API_TOKEN";
+
+  /**
+   * Header name for the dapr api token environment variable name.
+   */
+  public static final String DAPR_API_TOKEN_HEADER = "dapr-api-token";
+
   /**
    * Base path to invoke methods.
    */