AWS Neptune Upgrade issue

Hi - There was an issue in some Neptune engine versions (starting with 1.2.1) where the pg/stream endpoint stopped working. For now, please use propertygraph/stream instead with the 1.3.4.0 engine version.

The pg/stream endpoint should work again starting with engine version 1.4.1.0

We will take a note to add an appropriate comment to the documentation. Thank you for calling this out.

The error you're encountering suggests that the endpoint you're using for Neptune Streams is incorrect. When working with Neptune Streams, it's important to use the correct API endpoint format.

Based on the error message "Bad route: /pg/stream", it appears that the endpoint format you're using is not valid for your Neptune version. The correct endpoint format for Neptune Streams should be something like /gremlin/stream or /sparql/stream depending on the graph model you're using, not /pg/stream.

When upgrading Neptune versions, you need to ensure that you're using the correct API endpoints that are compatible with your current engine version. The error "BadRequestException" with "Bad route" indicates that the route you're trying to access doesn't exist in your Neptune instance.

I recommend checking the Neptune Streams documentation for your specific version (1.3.4.0) to confirm the correct endpoint format. Make sure you're using the appropriate stream endpoint that matches your graph model (Gremlin, SPARQL, etc.) rather than "pg/stream".

If you continue to experience issues, you might want to check if there are any pending maintenance actions that need to be completed before the upgrade is fully effective, as sometimes upgrade-related issues can occur if previous actions haven't been fully completed.
Sources
Use Neptune Streams as a lambda event source mapping? | AWS re:Post
Neptune Streams API Exceptions - Amazon Neptune