Module:Wikibase utils

Module documentation[create] [purge]

You might want to create a documentation page for this Scribunto module.
Editors can experiment in this module's sandbox (create | mirror) and testcases (edit | run) pages.
Add categories to the /doc subpage. Subpages of this module.

--[=[
Utility functions for handling Wikibase entity data

Functions in this module should be highly generic
]=]

local p = {} --p stands for package

--[=[
Get the entity for a QID, or a page title
]=]
function p.getEntity( titleOrQid ) 
	local item
	local t = type( titleOrQid )
	if t == 'table' then
		-- this is a title object
		item = mw.wikibase.getEntity(
			mw.wikibase.getEntityIdForTitle( titleOrQid.fullText )
		)
	elseif t == 'number' then
		-- construct a QID string
		item = mw.wikibase.getEntity( 'Q' .. titleOrQid )
	elseif t == 'string' then
		if string.match( titleOrQid, 'Q%d+$', 1 ) then
			-- it's a QID
			item = mw.wikibase.getEntity( titleOrQid )
		else
			-- assume it's a page title string
			item = mw.wikibase.getEntity(
				mw.wikibase.getEntityIdForTitle( titleOrQid )
			)
		end
	end
	return item
end

--[=[
Return a table of qualifiers for a statement with the given qualifier property

If the statement does not have that qualifier, or has no qualifiers at all,
return an empty table.
]=]
function p.getQualifiersOfStatementWithPid( statement, wantedQualifierPid )
	local qualifiers = statement.qualifiers or {}
	local matchingQualifiers = qualifiers[ wantedQualifierPid ] or {}
	return matchingQualifiers
end

--[=[
Return the value Qid of a snak
Returns nil if the snak datatype is not wikibase-item or has no value
--]=]
function p.getSnakValueQid( snak )
	-- bad data type
	if snak.snaktype ~= 'value' or snak.datatype ~= 'wikibase-item' or snak.datavalue.type ~= 'wikibase-entityid' then
		return nil
	end
	return snak.datavalue.value.id
end

--[=[
Return the year of a date snak
Returns nil if the snak datatype is not type 'time' or has no value
--]=]
function p.getSnakValueYear( snak )
	-- bad data type
	if snak.snaktype ~= 'value' or snak.datatype ~= 'time' or snak.datavalue.type ~= 'time' then
		return nil
	end
	local yrStr = string.gsub( snak.datavalue.value.time, '[+-]?(%d+)-.*', '%1' )
	return tonumber( yrStr )
end

return p