Merge pull request #1340 from walterlife/workflow-client-java

[ISSUE #1091] java sdk add workflow client 
close #1091

eventmesh-sdk-java/src/main/java/org/apache/eventmesh/client/workflow/EventMeshWorkflowClient.java

@@ -0,0 +1,62 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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.apache.eventmesh.client.workflow;
+
+import org.apache.eventmesh.client.selector.Selector;
+import org.apache.eventmesh.client.selector.SelectorFactory;
+import org.apache.eventmesh.client.selector.ServiceInstance;
+import org.apache.eventmesh.client.workflow.config.EventMeshWorkflowClientConfig;
+import org.apache.eventmesh.common.protocol.workflow.protos.ExecuteRequest;
+import org.apache.eventmesh.common.protocol.workflow.protos.ExecuteResponse;
+import org.apache.eventmesh.common.protocol.workflow.protos.WorkflowGrpc;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import io.grpc.ManagedChannel;
+import io.grpc.ManagedChannelBuilder;
+
+public class EventMeshWorkflowClient {
+
+    private static final Logger logger = LoggerFactory.getLogger(EventMeshWorkflowClient.class);
+    private final EventMeshWorkflowClientConfig clientConfig;
+
+    public EventMeshWorkflowClient(EventMeshWorkflowClientConfig clientConfig) {
+        this.clientConfig = clientConfig;
+    }
+
+    public WorkflowGrpc.WorkflowBlockingStub getWorkflowClient() throws Exception {
+        Selector selector = SelectorFactory.get(clientConfig.getSelectorType());
+        if (selector == null) {
+            throw new Exception(String.format("selector=%s not register.please check it.", clientConfig.getSelectorType()));
+        }
+        ServiceInstance instance = selector.selectOne(clientConfig.getServerName());
+        if (instance == null) {
+            throw new Exception("workflow server is not running.please check it.");
+        }
+        ManagedChannel channel = ManagedChannelBuilder.forAddress(instance.getHost(), instance.getPort()).usePlaintext().build();
+        return WorkflowGrpc.newBlockingStub(channel);
+    }
+
+    public ExecuteResponse execute(ExecuteRequest request) throws Exception {
+        WorkflowGrpc.WorkflowBlockingStub workflowClient = getWorkflowClient();
+        ExecuteResponse response = workflowClient.execute(request);
+        logger.info("received response " + response.toString());
+        return response;
+    }
+}

eventmesh-sdk-java/src/main/java/org/apache/eventmesh/client/workflow/config/EventMeshWorkflowClientConfig.java

@@ -0,0 +1,33 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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.apache.eventmesh.client.workflow.config;
+
+import lombok.Builder;
+import lombok.Data;
+import lombok.ToString;
+
+@Data
+@Builder
+@ToString
+public class EventMeshWorkflowClientConfig {
+    @Builder.Default
+    private String serverName = "eventmesh-workflow";
+
+    @Builder.Default
+    private String selectorType = "nacos";
+}