Emulating production environment on local machine with Docker

[AllenEllis]

I'm pretty new to Docker, and I'm following the Getting Up and Running Locally with Docker guide as my reference.

I'm specifically trying to learn more about this idea:

Generally, if you want to emulate production environment use production.yml instead. And this is true for any other actions you might need to perform: whenever a switch is required, just do it!

Which implies that I should be able to, in theory, use docker-compose to build and launch the production environment on my development machine.

In practice, this doesn't work for a few reasons:

• The traefik container tries to request certificates for my FQDN, which of course fail.
• traefik seems to only accept traffic bound for my FQDN, which of course is routed to my real production server.

I thought I might be able to work around this by adding some entires to my local /etc/hosts file:

127.0.0.1       django
127.0.0.1       flower
127.0.0.1       nginx
127.0.0.1       myfqdn.example.com

Even with this, these URLs each fail in their own ways in my browser:

• http://django:5000/ - HTTP 403 response
• http://flower:5555/ - HTTP 404 response
• http://nginx:80 - redirects to HTTPS, then a HTTP 404 response
• http://myfqdn.example.com - redirects to HTTPS, then a "Bad Gateway" response

I've tried looking through traefik.yml but nothing seems to explain these responses to me. Does anyone have any tips for making this work?

[AllenEllis]

Hi, ok I think I've answered my own question.

Setting my FQDN to 127.0.0.1 in my /etc/hosts file is the key trick. The others aren't accurate because those containers don't expose their ports directly anyway.

It looks like what happened is I wasn't waiting long enough for my Django container to finish booting up. My production container is set to push to S3, and I believe the collectstatic action was working in the background and so that's why traefik was (correctly) reporting that my django container was not yet ready to receive traffic.

After waiting about 4 minutes, it finished booting and it appears to be working!