Example for guaranteed processing with exactly-once semantics

To achieve exactly-once semantics with the ElasticsearchIndex operator:

• The operator must be part of a consistent region. In case of failures tuples are replayed by the source operator.
• In order to overwrite existing documents, ensure that the idNameAttribute parameter set, for an input stream attribute containing a unique key.

composite Main {
    param
        expression<rstring> $indexName: getSubmissionTimeValue("indexName", "index-sample");

    graph

        () as JCP = JobControlPlane() {}

        @consistent(trigger=periodic, period=5.0)
        stream<rstring key, uint64 dummy> Documents = Beacon() {
            param
                period: 0.01;
            output
                Documents : key = "SAMPLE"+(rstring) IterationCount();
        }

        () as ElasticsearchSink = ElasticsearchIndex(Documents) {
            param
                indexName: $indexName;
                idNameAttribute: key;
        }
}