I deployed Peertube via Docker but did not use the included nginx docker container and instead put Peertube behind an Apache httpd reverse proxy.
I was getting the error : Cannot retrieve OAuth Client credentials: undefined
when loading the peertube page
and the error client invalid
when attempting to log in.
The cause was that I wasn't passing the host header through Apache because I was missing the ProxyPreserveHost On
directive.
I added this and resolved the issue