1 module:set_global()

     2 

     3 local function return_args_after_calling(f, ...)

     4 	f();

     5 	return ...

     6 end

     7 

     8 local function time_method(module, store_name, store_type, method_name, method_function)

     9 	local opt_use_tags = module:get_option_boolean("measure_storage_tagged_metric", false);

    10 

    11 	local metric_name, metric_tags;

    12 	if opt_use_tags then

    13 		metric_name, metric_tags = "storage_operation", ("store_name:%s,store_type:%s,store_operation:%s"):format(store_name, store_type, method_name);

    14 	else

    15 		metric_name = store_name.."_"..store_type.."_"..method_name;

    16 	end

    17 	local measure_operation_started = module:measure(metric_name, metric_tags);

    18 

    19 	return function (...)

    20 		module:log("debug", "Measuring storage operation %s (%s)", metric_name, metric_tags or "no tags");

    21 		local measure_operation_complete = measure_operation_started();

    22 		return return_args_after_calling(measure_operation_complete, method_function(...));

    23 	end;

    24 end

    25 

    26 local function wrap_store(module, store_name, store_type, store)

    27 	local new_store = setmetatable({}, {

    28 		__index = function (t, method_name)

    29 			local original_method = store[method_name];

    30 			if type(original_method) ~= "function" then

    31 				if original_method then

    32 					rawset(t, method_name, original_method);

    33 				end

    34 				return original_method;

    35 			end

    36 			local timed_method = time_method(module, store_name, store_type, method_name, original_method);

    37 			rawset(t, method_name, timed_method);

    38 			return timed_method;

    39 		end;

    40 	});

    41 	return new_store;

    42 end

    43 

    44 local function hook_event(module)

    45 	module:hook("store-opened", function(event)

    46 		event.store = wrap_store(module, event.store_name, event.store_type, event.store);

    47 	end);

    48 end

    49 

    50 function module.load()

    51 	hook_event(module);

    52 end

    53 

    54 function module.add_host(module)

    55 	hook_event(module);

    56 end