core.moduleapi: Add :get_option_period for parsing time intervals

E.g. for use in mod_mam and others that take an amount of time before
some (usually cleanup) action is taken.

.luacheckrc

@@ -77,6 +77,7 @@ files["plugins/"] = {
 		"module.get_option_inherited_set",
 		"module.get_option_number",
 		"module.get_option_path",
+		"module.get_option_period",
 		"module.get_option_scalar",
 		"module.get_option_set",
 		"module.get_option_string",

CHANGES

@@ -42,6 +42,7 @@ TRUNK
 
 - Config interface API can require that string values be picked from a provided set
 - Acceptable interval can be specified for number options
+- Method for parsing time periods / intervals from config
 
 ## Changes
 

core/features.lua

@@ -19,5 +19,6 @@ return {
 		-- new moduleapi methods
 		"getopt-enum";
 		"getopt-interval";
+		"getopt-period";
 	};
 };

core/moduleapi.lua

@@ -21,6 +21,7 @@ local format = require "prosody.util.format".format;
 local jid_node = require "prosody.util.jid".node;
 local jid_split = require "prosody.util.jid".split;
 local jid_resource = require "prosody.util.jid".resource;
+local human_io = require "prosody.util.human.io";
 
 local t_insert, t_remove, t_concat = table.insert, table.remove, table.concat;
 local error, setmetatable, type = error, setmetatable, type;
@@ -253,6 +254,20 @@ function api:get_option_number(name, default_value, min, max)
 	return ret;
 end
 
+function api:get_option_period(name, default_value)
+	local value = self:get_option_scalar(name, default_value);
+	local num = tonumber(value);
+	if num then
+		-- assume seconds
+		return num;
+	end
+	local ret = human_io.parse_duration(value);
+	if value ~= nil and ret == nil then
+		self:log("error", "Config option '%s' not understood, expecting a period", name);
+	end
+	return ret;
+end
+
 function api:get_option_boolean(name, ...)
 	local value = self:get_option_scalar(name, ...);
 	if value == nil then