SyncStack.setJSON skips single item in "items" array

[victor-pariente-edo]

Description:
The SyncStack.setJSON method is incorrectly handling scenarios where the "items" key in the provided JSONObject contains a single item.
Instead of processing this single item, the current logic within the else block (when itemsObj is not a JSONArray) logs a warning and initializes an empty syncItems list, effectively skipping the data.

Code Snippet:

protected synchronized void setJSON(@NotNull JSONObject jsonobject) {
    if (jsonobject == null) {
        throw new IllegalArgumentException("JSON object cannot be null.");
    }

    this.receiveJson = jsonobject;

    if (receiveJson.has("items")) {
        Object itemsObj = receiveJson.opt("items");
        if (itemsObj instanceof JSONArray) {
            JSONArray jsonArray = (JSONArray) itemsObj;
            syncItems = new ArrayList<>();
            for (int i = 0; i < jsonArray.length(); i++) {
                JSONObject jsonItem = jsonArray.optJSONObject(i);
                if (jsonItem != null) {
                    syncItems.add(sanitizeJson(jsonItem));
                }
            }
        } else {
            logger.warning("'items' is not a valid list. Skipping processing."); // ✅ Prevent crashes
            syncItems = new ArrayList<>();
        }
    } else {
        syncItems = new ArrayList<>();
    }
}

Observed Behavior:

When the "items" key in the receiveJson JSONObject contains a single JSON object (not a JSONArray of one element), the code enters the else block and skips processing this item. The syncItems list remains empty in this case.

Expected Behavior:

When the "items" key contains only a single JSON object, it should be treated as a single item to be processed and added to the syncItems list.

Suggested Solution:

The else block should be modified to handle the case where itemsObj is a single JSONObject. A possible solution would be to check if itemsObj is an instance of JSONObject and, if so, create a new ArrayList, add the sanitized itemsObj to it, and assign it to syncItems.

        } else {
            if (itemsObj instanceof JSONObject) {
                syncItems = new ArrayList<>();
                syncItems.add(sanitizeJson((JSONObject) itemsObj));
            } else {
                logger.warning("'items' is not a valid list. Skipping processing."); // ✅ Prevent crashes
                syncItems = new ArrayList<>();
            }
        }

Impact:

This issue leads to data loss or incomplete synchronization when the "items" payload from Contentstack contains a single entry. As there is any exception thrown, we consider the execution as completed, and we are updating the sync token, which leads to data loss.