statsmanager: Refactor to simplify logic. Notably renames 'statistics_provider' to 'statistics', and external libs now just begin with ':'

1 files changed, 66 insertions, 59 deletions

diff --git a/core/statsmanager.lua b/core/statsmanager.lua
index 19d5860e..67702dd9 100644
--- a/core/statsmanager.lua
+++ b/core/statsmanager.lua
@@ -4,42 +4,53 @@ local log = require "util.logger".init("stats");
 local timer = require "util.timer";
 local fire_event = prosody.events.fire_event;
 
-local stats_config = config.get("*", "statistics_interval");
-local stats_interval = tonumber(stats_config);
+local stats_interval_config = config.get("*", "statistics_interval");
+local stats_interval = tonumber(stats_interval_config);
 if stats_config and not stats_interval then
 	log("error", "Invalid 'statistics_interval' setting, statistics will be disabled");
 end
 
-local stats_provider_config = config.get("*", "statistics_provider");
-local stats_provider = stats_provider_config or "internal";
+local stats_provider_name;
+local stats_provider_config = config.get("*", "statistics");
+local stats_provider = stats_provider_config;
+
+if not stats_provider and stats_interval then
+	stats_provider = "internal";
+elseif stats_provider and not stats_interval then
+	stats_interval = 60;
+end
 
 local builtin_providers = {
 	internal = "util.statistics";
 	statsd = "util.statsd";
 };
 
-if stats_provider:match("^library:") then
-	stats_provider = stats_provider:match(":(.+)$");
-else
-	stats_provider = builtin_providers[stats_provider];
-	if not stats_provider then
-		log("error", "Unrecognized built-in statistics provider '%s', using internal instead", stats_provider_config);
-		stats_provider = builtin_providers["internal"];
-	end
-end
 
-local have_stats_provider, stats_lib = pcall(require, stats_provider);
+local stats, stats_err = false, nil;
 
-local stats, stats_err;
+if stats_provider then
+	if stats_provider:sub(1,1) == ":" then
+		stats_provider = stats_provider:sub(2);
+		stats_provider_name = "external "..stats_provider;
+	elseif stats_provider then
+		stats_provider_name = "built-in "..stats_provider;
+		stats_provider = builtin_providers[stats_provider];
+		if not stats_provider then
+			log("error", "Unrecognized statistics provider '%s', statistics will be disabled", stats_provider_config);
+		end
+	end
 
-if not have_stats_provider then
-	stats, stats_err = nil, stats_lib;
-else
-	local stats_config = config.get("*", "statistics_config");
-	stats, stats_err = stats_lib.new(stats_config);
+	local have_stats_provider, stats_lib = pcall(require, stats_provider);
+	if not have_stats_provider then
+		stats, stats_err = nil, stats_lib;
+	else
+		local stats_config = config.get("*", "statistics_config");
+		stats, stats_err = stats_lib.new(stats_config);
+		stats_provider_name = stats_lib._NAME or stats_provider_name;
+	end
 end
 
-if not stats then
+if stats == nil then
 	log("error", "Error loading statistics provider '%s': %s", stats_provider, stats_err);
 end
 
@@ -53,51 +64,47 @@ if stats then
 		local f = assert(stats[type], "unknown stat type: "..type);
 		return f(name);
 	end
-end
 
-if stats_interval then
-	log("debug", "Statistics collection is enabled every %d seconds", stats_interval);
-
-	local mark_collection_start = measure("times", "stats.collection");
-	local mark_processing_start = measure("times", "stats.processing");
-
-	function collect()
-		local mark_collection_done = mark_collection_start();
-		fire_event("stats-update");
-		mark_collection_done();
-
-		if stats.get_stats then
-			changed_stats, stats_extra = {}, {};
-			for stat_name, getter in pairs(stats.get_stats()) do
-				local type, value, extra = getter();
-				local old_value = latest_stats[stat_name];
-				latest_stats[stat_name] = value;
-				if value ~= old_value then
-					changed_stats[stat_name] = value;
-				end
-				if extra then
-					stats_extra[stat_name] = extra;
+	if stats_interval then
+		log("debug", "Statistics enabled using %s provider, collecting every %d seconds", stats_provider_name, stats_interval);
+
+		local mark_collection_start = measure("times", "stats.collection");
+		local mark_processing_start = measure("times", "stats.processing");
+
+		function collect()
+			local mark_collection_done = mark_collection_start();
+			fire_event("stats-update");
+			mark_collection_done();
+
+			if stats.get_stats then
+				changed_stats, stats_extra = {}, {};
+				for stat_name, getter in pairs(stats.get_stats()) do
+					local type, value, extra = getter();
+					local old_value = latest_stats[stat_name];
+					latest_stats[stat_name] = value;
+					if value ~= old_value then
+						changed_stats[stat_name] = value;
+					end
+					if extra then
+						stats_extra[stat_name] = extra;
+					end
 				end
+				local mark_processing_done = mark_processing_start();
+				fire_event("stats-updated", { stats = latest_stats, changed_stats = changed_stats, stats_extra = stats_extra });
+				mark_processing_done();
 			end
-			local mark_processing_done = mark_processing_start();
-			fire_event("stats-updated", { stats = latest_stats, changed_stats = changed_stats, stats_extra = stats_extra });
-			mark_processing_done();
+			return stats_interval;
 		end
-		return stats_interval;
+		timer.add_task(stats_interval, collect);
+		prosody.events.add_handler("server-started", function () collect() end, -1);
+	else
+		log("debug", "Statistics enabled using %s provider, collection is disabled", stats_provider_name);
 	end
-	timer.add_task(stats_interval, collect);
-	prosody.events.add_handler("server-started", function () collect() end, -1);
+else
+	log("debug", "Statistics disabled");
+	function measure() return measure; end
 end
 
-if not stats_interval and stats_provider == "util.statistics" then
-	log("debug", "Statistics collection is disabled");
-	-- nop
-	function measure()
-		return measure;
-	end
-	function collect()
-	end
-end
 
 return {
 	measure = measure;