Add formdata parser (#5749)

internal/config/config.go

@@ -1726,6 +1726,18 @@ func getParserConfig(name string, tbl *ast.Table) (*parsers.Config, error) {
 		}
 	}
 
+	if node, ok := tbl.Fields["form_data_tag_keys"]; ok {
+		if kv, ok := node.(*ast.KeyValue); ok {
+			if ary, ok := kv.Value.(*ast.Array); ok {
+				for _, elem := range ary.Value {
+					if str, ok := elem.(*ast.String); ok {
+						c.FormDataTagKeys = append(c.FormDataTagKeys, str.Value)
+					}
+				}
+			}
+		}
+	}
+
 	c.MetricName = name
 
 	delete(tbl.Fields, "data_format")
@@ -1767,6 +1779,7 @@ func getParserConfig(name string, tbl *ast.Table) (*parsers.Config, error) {
 	delete(tbl.Fields, "csv_timestamp_column")
 	delete(tbl.Fields, "csv_timestamp_format")
 	delete(tbl.Fields, "csv_trim_space")
+	delete(tbl.Fields, "form_data_tag_keys")
 
 	return c, nil
 }