How to get php-fpm to log to stdout / stderr when running in a docker container
Ok, the way to do this is to send the error and the access logs to the following address:
/proc/self/fd/2
In php5-fpm.log add:
access.log = /proc/self/fd/2
error_log = /proc/self/fd/2
Note that the baked in fpm config for the latest version of the official PHP fpm docker image writes to the standard streams:
error_log = /proc/self/fd/2
...
; if we send this to /proc/self/fd/1, it never appears
access.log = /proc/self/fd/2