New update logic

[Johnwickdev]

@Override public void processElement2(Document localDoc, Context ctx, Collector out) throws Exception { // Retrieve the state stored earlier Document mongoDoc = mongoState.value();

if (mongoDoc != null) {
    // Create a new document to store only the changed fields
    Document deltaDoc = new Document("operation", "update")
                            .append("CSPA", localDoc.getString("CSPA"))
                            .append("date", localDoc.getString("date"))
                            .append("version", localDoc.getString("version"))
                            .append("layout_name", localDoc.getString("layout_name"));

    Document changedFields = new Document();

    for (String key : localDoc.get("document", Document.class).keySet()) {
        Object localValue = localDoc.get("document", Document.class).get(key);
        Object mongoValue = mongoDoc.get("document", Document.class).get(key);

        if (!localValue.equals(mongoValue)) {
            changedFields.append(key, "Changed from " + mongoValue + " to " + localValue);
        }
    }

    if (!changedFields.isEmpty()) {
        deltaDoc.append("document", changedFields);
        out.collect(deltaDoc); // Emit the delta document
    }

} else {
    // If no matching document in MongoDB, treat this as a new record
    Document deltaDoc = new Document("operation", "insert")
                            .append("new", localDoc);
    out.collect(deltaDoc); // Emit the new document
}

// Update state
mongoState.update(localDoc);

}