message: open source fb303_status and getStatus
  Summary:
  Move fb_status into open source fb303 and rename it to fb303_status.
  Also add a getStatus() call to BaseService.
diff: /*
  - * Copyright (c) Facebook, Inc. and its affiliates.
  + * Copyright 2019-present Facebook, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  @@ -23,6 +23,18 @@ namespace php fb303
  namespace node_module fb303
  namespace go fb303.thrift.fb303_core
  +/**
  + * Common status reporting mechanism across all services
  + */
  +enum fb303_status {
  + DEAD = 0,
  + STARTING = 1,
  + ALIVE = 2,
  + STOPPING = 3,
  + STOPPED = 4,
  + WARNING = 5,
  +}
  +
  /**
  * Standard base service interface.
  *
  @@ -31,6 +43,11 @@ namespace go fb303.thrift.fb303_core
  */
  service BaseService {
  + /**
  + * Gets the status of this service
  + */
  + fb303_status getStatus() (priority='IMPORTANT')
  +
  /**
  * Returns a descriptive name of the service
  */
  