Add traceback to an execute error

Author: Totktonada

graphql/impl.lua

@@ -41,10 +41,16 @@ local function gql_execute(qstate, variables, operation_name)
 
     local root_value = {}
 
-    local ok, data = pcall(execute, state.schema, qstate.ast, root_value,
-        variables, operation_name)
+    local traceback
+    local ok, data = xpcall(function()
+        return execute(state.schema, qstate.ast, root_value, variables,
+            operation_name)
+    end, function(err)
+        traceback = debug.traceback()
+        return err
+    end)
     if not ok then
-        local err = utils.serialize_error(data)
+        local err = utils.serialize_error(data, traceback)
         return {errors = {err}}
     end
     return {

graphql/utils.lua

@@ -225,13 +225,21 @@ function utils.optional_require_rex()
     return rex, is_pcre2
 end
 
-function utils.serialize_error(err)
+function utils.serialize_error(err, traceback)
     if type(err) == 'string' then
-        return {message = utils.strip_error(err)}
+        return {
+            message = utils.strip_error(err),
+            traceback = traceback,
+        }
     elseif type(err) == 'cdata' and
             tostring(ffi.typeof(err)) == 'ctype<const struct error &>' then
-        return {message = tostring(err)}
+        return {
+            message = tostring(err),
+            traceback = traceback,
+        }
     elseif type(err) == 'table' and type(err.message) == 'string' then
+        local err = table.copy(err)
+        err.traceback = traceback
         return err
     end
 
@@ -243,6 +251,7 @@ function utils.serialize_error(err)
     return {
         message = message,
         orig_error = orig_error,
+        traceback = traceback,
     }
 end