Not being able to filter access logs since 3.5.0.2 about kong HOT 6 CLOSED

Hi @samugi ! Thanks for answering 😄

Unfortunately, the KONG_NGINX_HTTP_LOG_FORMAT does not work for us, cause it is being used to set the log format, but it does not allow setting the if= directive 😞 .

Basically, we would like to apply the following Nginx configuration to ensure that 2xx and 3xx requests aren't logged:

map $status $loggable {
    ~^[23]  0;
    default 1;
}

access_log /dev/stdout combined if=$loggable;

This was achievable before (Kong <3.5) by setting KONG_PROXY_ACCESS_LOG="/dev/stdout combined if=$loggable", but now this is not possible cause:

• The code forces to put the kong_log_format at the end of the line.
• The only way to bypass this is by setting KONG_PROXY_ACCESS_LOG=<file> <format>. Otherwise, the string does not match this regex and the code puts the kong_log_format at the end of the line.

Many thanks!

from kong.

Hi again 👋

I found the root problem. I was using the kong docker image (kong:3.5) and I thought that it was using Kong 3.5.0.2 (kong version returns Kong 3.5). After replacing the image by the kong/kong-gateway:3.5.0.2 the issue is solved!!

Many thanks for your help 🙏

from kong.

I've reviewed the code and the affected line was changed here feat(request-id): introduce unique Request ID

from kong.

Hi @alemuro thank you for reporting this. I am looking into the issue you described, in the meantime, could you check if the problem is resolved by using the KONG_NGINX_HTTP_LOG_FORMAT variable to set the log format? Thank you.

from kong.

Hi @alemuro and thank you for the additional details provided.

I was able to reproduce the problem on 3.5.0.0, but I believe that should've been fixed by #12073, in fact, the regex you linked should match the string /dev/stdout combined if=$loggable. To make sure, I tested this on kong/kong-gateway:3.5.0.2-ubuntu and got the expected result, where conditional logging using the if keyword is accepted. Using your filter, the conditional logging was applied correctly to only log "non 2xx/3xx" status codes.

Can you try with the image I tested and let me know, and in case the problem can still be reproduced, provide some steps that include the exact image you are testing with? Thank you!

from kong.

thank you @alemuro !

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