public static Map<String, Object> convert(Event event, Map<String, TemplateBuilder> converterMap) {
        Map<String, Object> mapped = new HashMap<>();
        for (Map.Entry<String, TemplateBuilder> entry : converterMap.entrySet()) {
            mapped.put(entry.getKey(), entry.getValue().build(event));
        }
        return mapped;
    }
Template builder used by {@link SinkMapper} to generate custom payload.
modules/siddhi-core/src/main/java/io/siddhi/core/util/transport/TemplateBuilder.java