feat(pipeline): Add pipeline execution cancellation entrypoint. (#75)

kayenta-orca/src/main/java/com/netflix/kayenta/orca/controllers/PipelineController.java

@@ -28,10 +28,12 @@
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.ConfigurableApplicationContext;
+import org.springframework.http.HttpStatus;
 import org.springframework.web.bind.annotation.PathVariable;
 import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestMethod;
+import org.springframework.web.bind.annotation.ResponseStatus;
 import org.springframework.web.bind.annotation.RestController;
 
 import javax.annotation.PostConstruct;
@@ -88,6 +90,15 @@ List<ExecutionLogEntry> logs(@PathVariable String executionId) {
     return executionLogRepository.getAllByExecutionId(executionId);
   }
 
+  @ApiOperation(value = "Cancel a pipeline execution")
+  @RequestMapping(value = "/{executionId}/cancel", method = RequestMethod.PUT)
+  @ResponseStatus(HttpStatus.ACCEPTED)
+  void cancel(@PathVariable String executionId) {
+    log.info("Cancelling pipeline execution {}...", executionId);
+
+    executionRepository.cancel(executionId);
+  }
+
   private static class FeatureNotEnabledException extends RuntimeException {
     public FeatureNotEnabledException(String message) {
       super(message);

kayenta-web/src/main/java/com/netflix/kayenta/controllers/CanaryController.java

@@ -86,6 +86,7 @@ public CanaryController(String currentInstanceId,
     }
   }
 
+  // TODO(duftler): Allow for user to be passed in.
   @ApiOperation(value = "Initiate a canary pipeline")
   @RequestMapping(consumes = "application/json", method = RequestMethod.POST)
   public String initiateCanary(@RequestParam(required = false) final String metricsAccountName,