node-red-node-cbor cannot handle BigInt

Which node are you reporting and issue on?

node-red-node-cbor

What are the steps to reproduce?

send a timestamp as integer to decode - the decoder exits with the error message "Bad Decode"

What happens?

the node-red-node-cbor plugin serializes the decoded result with JSON: https://github.com/node-red/node-red-nodes/blob/06a9c48395ab8ba707a0f265162df5c0c81dd74b/parsers/cbor/70-cbor.js#L19

As JSON does not support BigInt, this creates an error message when you are decoding a timestamp for example.

What did you expect to happen?

1. The decoder should decode correctly sent buffers without error message.
2. The error message should correspond to the actual error.

Proposed solution

1. I propose to add a replacer function and convert BigInt and other unsupported formats.
2. The error message "not a cbor buffer" is not always correct. I would prefer to use the actual error message.

Additionally, cbor-x library is out of date and should be updated.

Start in parsers/cbor/70-cbor.js around the linked serialization code and reproduce decoding a timestamp or other BigInt value. Verify that valid buffers decode without the JSON error and that failures report the underlying error; also review the requested cbor-x update. No test file is named in the issue.