Spring Update Content-Length when body changed by Interceptor

Hi maintainers, while working with the framework, I discovered a bug that I believe warrants attention.

In the org.springframework.http.client.InterceptingClientHttpRequest , the request body may be changed by interceptors, but Content-Length in the request headers didn't. This may cause the server receive the incorrect request body. I created a simple demo to show this bug . DEMO

The fix for this is to reset the Content-Length before sending the request at org.springframework.http.client.InterceptingClientHttpRequest.InterceptingRequestExecution#execute

Comment From: bclozel

I am not sure we should do this. Do we really set the content length header in all cases and for all converters? If an interceptor is changing the request body I would argue it needs to change the content type as well as the content length of it was set already. I think some http clients can send bodies with chunked transfer encoding.

Comment From: imzhoukunqiang

I am not sure we should do this. Do we really set the content length header in all cases and for all converters? If an interceptor is changing the request body I would argue it needs to change the content type as well as the content length of it was set already. I think some http clients can send bodies with chunked transfer encoding.

I agree with your point of view. I'm not sure whether setting Content-Length is the responsibility of the user or the framework. However, typically when we use RestTemplate, we do not set Content-Length, and it is handled by the framework.

And if after executing the interceptor chain, the Content-Length exists in the request header and does not equal body.length, should it be corrected to the correct value?