What is the rate limit for GCE instance metadata service?
问题 On a GCP compute environment, I need to get an id_token (expires every 3600s) to make service-to-service authentication (using GCF, Cloud Run etc). I get this id_token from the instance metadata service: http://metadata/computeMetadata/v1/instance/service-accounts/default/identity?audience=[...] Instead of implementing some form of caching+TTL for this identity token, I'm curious if I can call this endpoint every time I will make an outbound RPC (I might make a lot). That's why I'm curious: