Sanic 'request.url' can be invalid

[jacebrowning]

See the workaround added here: https://github.com/jacebrowning/memegen/pull/798/files

I believe this is caused by SERVER_NAME being a URL rather than just hostname, but without that the Swagger UI fails to load in production.

[BreadBreadington]

Is this related to the 500 statuscode I get from certain URLs?

For example if I try to use this image with the API, it generates the link fine but the link itself returns error 500
URL: https://cdn.discordapp.com/attachments/222559742831099905/290813528917671938/tumblr_mhetw0c1Hq1r4xfc2o1_500.png

Memegen out: https://api.memegen.link/images/custom/string/a.png?background=https://cdn.discordapp.com/attachments/222559742831099905/290813528917671938/tumblr_mhetw0c1Hq1r4xfc2o1_500.png