private String attributeMapToLines(final AttributeMap attributeMap, final String indent) {
        if (NullSafe.isEmptyMap(attributeMap)) {
            return "";
        } else {
            return attributeMap.entrySet()
                    .stream()
                    .sorted(Entry.comparingByKey())
                    .map(entry ->
                            NullSafe.string(indent) + entry.getKey() + ": " + entry.getValue())
                    .collect(Collectors.joining("\n"));
        }
    }
Handler class that forwards the request to a URL.
stroom-pipeline/src/main/java/stroom/pipeline/writer/HTTPAppender.java