Proxy Buffering Settings Cause Issues

[Hicham-Chahboune]

Is there an existing issue for this?

• I have searched the existing issues

Kong version ($ kong version)

3.7.0

Current Behavior

When sending a very large request, Nginx (of kong) buffers it in a file. However, in a plugin, if I attempt to read the body from the request, it doesn't retrieve the body from that file and returns an error. The solution I found is to increase the Nginx buffer size, which works, but this is not ideal, especially when receiving multiple large requests, as is my case.

Current Configuration:
proxy_buffering on;
proxy_buffer_size 32k;
proxy_buffers 64 16k;
proxy_busy_buffers_size 256k;
proxy_max_temp_file_size 200m;
proxy_temp_file_write_size 1024k;

ERROR MESSAGE:

a client request body is buffered to a temporary file /usr/local/kong/client_body_temp/0000000001
/usr/local/share/lua/5.1/MessagePack.lua:126: attempt to get length of local 'str' (a nil value)

Expected Behavior

Expected Behavior:

The body should be retrievable from the file without needing to increase the buffer size of nginx.

Steps To Reproduce

Steps to Reproduce:

• Send a very large request to kong.
• Attempt to read the body from the request within a plugin.
• Observe that the body is not retrieved from the file and an error is returned.

Anything else?

a client request body is buffered to a temporary file /usr/local/kong/client_body_temp/0000000001,
/usr/local/share/lua/5.1/MessagePack.lua:126: attempt to get length of local 'str'

[StarlightIbuki]

This is by design and not a bug for PDK.
It looks like you are using JS or Python PDK; currently, we do not support reading from cached files. We have a WIP PR to support it: a76d657 (#13158)