Updated LetsEncrypt docker-compose to fix 'links' service extension

[eduardohenriquearnold]

I am using the Letsencrypt example to deploy the service with a valid SSL certificate. Following these instructions I was not able to start the container with the following error: ERROR: Cannot extend service 'hub' in /home/ml/jupyterhub-deploy-docker/docker-compose.yml: services with 'links' cannot be extended.

I've modified the letsecrypt specific docker-compose.yml according to https://github.com/docker/compose/issues/1617 to allow service extension even with links. I have updated the README file accordingly.

I also noted that the jupyterhub Dockerfile requires .crt and .key files to be present in the secrets folder in order to build the image. So the user may need to create these empty files to avoid getting non-existent file errors. I thought about a nicer way to overcome this issue but this seemed to be the easiest one.

[Rafiot]

I had do to the same to get it work.

@eduardohenriquearnold thank you!

[priamai]

Same story here thanks for the fix!

[priamai]

I am getting this error now:

docker-compose -f docker-compose.yml -f examples/letsencrypt/docker-compose.yml up -d
ERROR: Couldn't find env file: /home/robo/jupyterhub-deploy-docker/secrets/postgres.env

I think there are also other changes in the makefile to make it fully working?

[manics]

This repository was very out of date so Lets-encrypt was removed. This greatly simplifies the setup, so you should be able to add Let-encrypt using a standard tutorial instead.