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## \[V3 REST API] Client error code

*This change impacts the**v3** REST APIs only (currently in open beta)*

We've updated the V3 API framework to return informative HTTP status codes for client errors. Now if the resource you're trying to update isn't found, you'll get a 404. Or, if you try to create a container with the same barcode as an existing one in the same registry, you'll get a 409.

You'll still get a 400 code for bad requests, and you'll also get a 400 if there are multiple different kinds of client errors (e.g. try to create a container with a nonsense projectId and also the same barcode as an existing container).

Before this change: most client errors were returned with a 400 code, even when the underlying cause was something like insufficient permissions or not found.