public void setDocsumReponse(String nodeId, int docId, String docsumClass, Map<String, Object> docsumValues) {
        docsums.put(new DocsumKey(nodeId, globalIdFrom(docId), docsumClass), docsumValues);
    }
Set to true to cause this to produce an error instead of a regular response
container-search/src/test/java/com/yahoo/search/dispatch/rpc/MockClient.java