@GET
  @Produces(MediaType.TEXT_PLAIN)
  @ApiOperation(value = "Get all action definitions",
      nickname = "ActionService#getActionDefinitions",
      response = ActionResponse.ActionResponseSwagger.class,
      responseContainer = RESPONSE_CONTAINER_LIST)
  @ApiImplicitParams({
      @ApiImplicitParam(name = QUERY_FIELDS, value = QUERY_FILTER_DESCRIPTION,
          defaultValue = "Actions/action_name",
          dataType = DATA_TYPE_STRING, paramType = PARAM_TYPE_QUERY),
      @ApiImplicitParam(name = QUERY_SORT, value = QUERY_SORT_DESCRIPTION,
          defaultValue = "Actions/action_name.asc",
          dataType = DATA_TYPE_STRING, paramType = PARAM_TYPE_QUERY),
      @ApiImplicitParam(name = QUERY_PAGE_SIZE, value = QUERY_PAGE_SIZE_DESCRIPTION, defaultValue = DEFAULT_PAGE_SIZE, dataType = DATA_TYPE_INT, paramType = PARAM_TYPE_QUERY),
      @ApiImplicitParam(name = QUERY_FROM, value = QUERY_FROM_DESCRIPTION, defaultValue = DEFAULT_FROM, dataType = DATA_TYPE_STRING, paramType = PARAM_TYPE_QUERY),
      @ApiImplicitParam(name = QUERY_TO, value = QUERY_TO_DESCRIPTION, dataType = DATA_TYPE_STRING, paramType = PARAM_TYPE_QUERY)
  })
  @ApiResponses(value = {
      @ApiResponse(code = HttpStatus.SC_OK, message = MSG_SUCCESSFUL_OPERATION),
      @ApiResponse(code = HttpStatus.SC_UNAUTHORIZED, message = MSG_NOT_AUTHENTICATED),
      @ApiResponse(code = HttpStatus.SC_INTERNAL_SERVER_ERROR, message = MSG_SERVER_ERROR)
  })
  public Response getActionDefinitions(String body, @Context HttpHeaders headers, @Context UriInfo ui) {
    return handleRequest(headers, body, ui, Request.Type.GET, createActionDefinitionResource(null));
  }
Handles: GET  /actions
Get all action definitions.

@param headers http headers
@param ui      uri info
@return action definition collection resource representation
ambari-server/src/main/java/org/apache/ambari/server/api/services/ActionService.java