add envclusters interface

apollo-portal/src/main/java/com/ctrip/framework/apollo/openapi/dto/OpenEnvClusterDTO.java

+package com.ctrip.framework.apollo.openapi.dto;
+
+import java.util.Set;
+
+public class OpenEnvClusterDTO {
+
+  private String env;
+  private Set<String> clusters;
+
+  public String getEnv() {
+    return env;
+  }
+
+  public void setEnv(String env) {
+    this.env = env;
+  }
+
+  public Set<String> getClusters() {
+    return clusters;
+  }
+
+  public void setClusters(Set<String> clusters) {
+    this.clusters = clusters;
+  }
+}

apollo-portal/src/main/java/com/ctrip/framework/apollo/openapi/v1/controller/AppController.java

+package com.ctrip.framework.apollo.openapi.v1.controller;
+
+import com.ctrip.framework.apollo.common.dto.ClusterDTO;
+import com.ctrip.framework.apollo.common.utils.BeanUtils;
+import com.ctrip.framework.apollo.core.enums.Env;
+import com.ctrip.framework.apollo.openapi.dto.OpenEnvClusterDTO;
+import com.ctrip.framework.apollo.portal.PortalSettings;
+import com.ctrip.framework.apollo.portal.service.ClusterService;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import java.util.LinkedList;
+import java.util.List;
+
+@RestController("openapiAppController")
+@RequestMapping("/openapi/v1")
+public class AppController {
+
+  @Autowired
+  private PortalSettings portalSettings;
+  @Autowired
+  private ClusterService clusterService;
+
+  @RequestMapping("/apps/{appId}/envclusters")
+  public List<OpenEnvClusterDTO> loadEnvClusterInfo(@PathVariable String appId){
+
+    List<OpenEnvClusterDTO> envClusters = new LinkedList<>();
+
+    List<Env> envs = portalSettings.getActiveEnvs();
+    for (Env env : envs) {
+      OpenEnvClusterDTO envCluster = new OpenEnvClusterDTO();
+
+      envCluster.setEnv(env.name());
+      List<ClusterDTO> clusterDTOs = clusterService.findClusters(env, appId);
+      envCluster.setClusters(BeanUtils.toPropertySet("name", clusterDTOs));
+
+      envClusters.add(envCluster);
+    }
+
+    return envClusters;
+
+  }
+
+}