Fix Bug : Server sent event get blocked when ModifyResponseBodyGatewayFilterFactory is enable

[vineetkala11]

Fixes #2775

ModifyResponseBodyGatewayFilterFactory is blocker for SSE based resources because writeWith method of ModifiedServerHttpResponse is responsible to modify response body for stream and non stream mime-type, writeWith convert response body to Mono, this behavior of writeWith is a blocker for stream type SSE.

Due to this issue consumer of SSE endpoint getting all events in one go instead of in form of stream. Without ModifyResponseBodyGatewayFilterFactory things works perfectly.

This PR contains fix for this issue and idea is to handle writeAndFlushWith method differently for stream mime type, as writeAndFlushWith being called by writer only when response content type is of Stream media type.

Please review this PR, if looks ok please approve it.

[vineetkala11]

Hello @spencergibb

Could you please have a look to this PR and share you feedbacks. This issue is a show stopper for those who enable ModifyResponseBodyGatewayFilterFactory to modify response body and response's media-type is text/event-stream.

Thanks

[vineetkala11]

Hello @spencergibb

Due to below issue, build check was not completed within the given time frame. I am not sure is it due to environment issue at that moment or some other reason.

[vineetkala11]

Hello @spencergibb ,

I've seen that the conflicts aren't too big. Is it okay if I check them out and resolve them?

[spencergibb]

Go right ahead

[vineetkala11]

Hello @spencergibb , please have a look, conflicts are resolved.

[vineetkala11]

Hello @spencergibb , its my bad, I used web view to resolve conflicts and missed one unused import, please retrigger build. I hope this time things goes well 🤞

[vineetkala11]

@spencergibb, any update on this PR?

[vineetkala11]

Hello @spencergibb , Do you have any news on this PR? Are you thinking of classifying it as a bug or a new enhancement?