Function source_with_params 

pub fn source_with_params(source: &str, params: Option<&Value>) -> String

VAPP-122: source with params appended as its query, for the bind action (sourceWithParams): keys sorted, key and value percent-encoded, a null value skipped, an object or array as JSON, after ? or &. A repeated key parses with the last value, so a param overrides the source’s own.