feat(monitored deploy): expose monitor deploy orca endpoints

expose endpoint from spinnaker/orca#3138

gate-web/src/main/groovy/com/netflix/spinnaker/gate/controllers/CapabilitiesController.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright 2019 Netflix, Inc.
+ *
+ * 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 com.netflix.spinnaker.gate.controllers;
+
+import com.netflix.spinnaker.gate.security.RequestContext;
+import com.netflix.spinnaker.gate.services.internal.OrcaServiceSelector;
+import io.swagger.annotations.ApiOperation;
+import java.util.List;
+import lombok.RequiredArgsConstructor;
+import org.springframework.web.bind.annotation.*;
+
+@RestController
+@RequestMapping("/capabilities")
+@RequiredArgsConstructor
+public class CapabilitiesController {
+
+  private final OrcaServiceSelector orcaService;
+
+  @ApiOperation(value = "Retrieve the list configured deployment monitors", response = List.class)
+  @GetMapping(value = "/deploymentMonitors")
+  List<Object> getDeploymentMonitors() {
+    return orcaService.withContext(RequestContext.get()).getDeploymentMonitors();
+  }
+}

gate-web/src/main/groovy/com/netflix/spinnaker/gate/services/internal/OrcaService.groovy

@@ -137,4 +137,7 @@ interface OrcaService {
 
   @POST("/concourse/stage/start")
   Response concourseStageExecution(@Query("stageId") String stageId, @Query("job") String job, @Query("buildNumber") Integer buildNumber, @Body String emptyBody);
+
+  @GET("/capabilities/deploymentMonitors")
+  List<Object> getDeploymentMonitors();
 }