I am using envoy filter to write a lua HTTP filter that can extract the user claims from a JWT token. Since the payload in the JWT token is base64 encoded, I am using lua to decode it and parse the claims to extract email id. However, I did not find any preinstalled libraries which can help with extracting payload from a jwt token, decoding base64 or convert the decoded payload from string to a table format.
Am I missing something? or do I need to build these libraries into envoy? If I need to install them, can someone help with the documentation for how to do it?
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