Why Jwt is the only supported format for bearer tokens in Spring Security?

[ShanyouYu-Sean]

Summary

Seems Jwt is the only supported format for bearer tokens in Spring Security 5.1.+, why? Is there any plans implement a way to verify normal bearer token with userinfo endpoint or token introspect endpoint?

Actual Behavior

Cannot verify normal bearer token with userinfo endpoint or token introspect endpoint in Spring Security 5.1.+.

Expected Behavior

Provide a way to verify normal bearer token with userinfo endpoint or token introspect endpoint.

Version

Spring Security 5.1.2.RELEASE

[jgrandja]

@ShanyouYu-Sean Token Introspection (opaque token) support is planned for 5.2. You can track the progress in #5200.