Update firstValue.lua

ProfessionalWiki · Nov 25, 2023 · 1f2a961 · 1f2a961
1 parent 6cc456d
commit 1f2a961
Showing 1 changed file with 7 additions and 2 deletions.
diff --git a/demoLua/firstValue.lua b/demoLua/firstValue.lua
@@ -1,10 +1,15 @@
-local sparql = require('SPARQL')
+local sparql = require('SPARQL') -- Load the SPARQL binding
 
 local p = {}
 
 function p.showFirstValue(frame)
 	local sparqlQuery = frame.args[1]
-	local queryResults = sparql.runQuery(sparqlQuery)
+	local queryResults = sparql.runQuery(sparqlQuery) -- Use the runQuery method
+
+	-- nil is returned if Blazegraph did not return a valid response
+	if queryResults == nil then
+		return ''
+	end
 
 	-- Replace "work" with the first SELECT variable in your SPARQL query
 	return queryResults['results']['bindings'][1]['work']['value']