Information regarding "Server servlet context path omitted when run with X-Forwarded-Prefix"

[heuristicservices]

This ticket could be closed, but I think it would be good to link this information to #2068 and #2058

I had another look at #2058

The suggested fix, to add

proxy_set_header X-Forwarded-Prefix $http_x_forwarded_prefix;

results in, on accessing http://localhost:8080/api/petstore/v3/api-docs/swagger-config

{"configUrl":"/petstore/v3/api-docs/swagger-config","oauth2RedirectUrl":"http://localhost:8080/petstore/swagger-ui/oauth2-redirect.html","url":"/petstore/v3/api-docs","validatorUrl":""}

which omits the /api prefix (the $http_x_forwarded_prefix nginx variable being probably set upstream connections to nginx, of which there are not any, so it defaults to "").

However the issue appears to be Spring-related, rather than related to springdoc-openapi. If an X-Forwarded-Prefix is present, then Spring will use this to replace the context-path; not append it to the context-path.

There was a discussion on whether it should replace or prepend here: spring-projects/spring-framework#18949

I think the desired behaviour can be achieved by the following:

proxy_set_header X-Forwarded-Prefix /api/petstore;

which results in the correct response, on accessing http://localhost:8080/api/petstore/v3/api-docs/swagger-config

{"configUrl":"/api/petstore/v3/api-docs/swagger-config","oauth2RedirectUrl":"http://localhost:8080/api/petstore/swagger-ui/oauth2-redirect.html","url":"/api/petstore/v3/api-docs","validatorUrl":""}

Thank you for looking at the original issue.

[bnasslahsen]

@heuristicservices,

No additonal actions required in springdoc-openapi side:
The original answer was related to your test case!
You have the answer here: #2068.
You just mentioned the same answer.