@Path("{hostName}/alert_history")
  public AlertHistoryService getAlertHistoryService(
      @Context jakarta.ws.rs.core.Request request,
      @PathParam("hostName") String hostName) {

    return new AlertHistoryService(m_clusterName, null, hostName);
  }
Gets the alert history service

@param request the request
@param hostName the host name
@return the alert history service
ambari-server/src/main/java/org/apache/ambari/server/api/services/HostService.java