Add mirrors for Ubuntu base image

[ndeepak-baseten]

🚀 What

Set mirrors for Ubuntu image. Other images including python-* are Debian-based, and deb.*.org already uses mirrors.

💻 How

Add a sed command to set configuration at build time.

🔬 Testing

TBD.

[squidarth]

is there a more declarative way to do this (rather than piping new content iN?

[ndeepak-baseten]

@squidarth Can be done, requires a bit more work:

1. apt-add-repository requires Debian release, so we need to discover and place that appropriately
2. apt uses the first repo it sees, so we have to pin priorities.

Looks like this:

# Add mirror repository
RUN add-apt-repository -y "deb http://mirror.ubuntu.com/ubuntu/ $(lsb_release -sc) main restricted universe multiverse"

# Set priority to prefer mirror.ubuntu.com
RUN echo "Package: *" > /etc/apt/preferences.d/ubuntu-mirrors && \
    echo "Pin: origin mirror.ubuntu.com" >> /etc/apt/preferences.d/ubuntu-mirrors && \
    echo "Pin-Priority: 600" >> /etc/apt/preferences.d/ubuntu-mirrors

This is more touchpoints and also overwrites the ubuntu-mirrors file. The sed solution is simpler, also seeing it on forums, do you feel strongly?

[squidarth]

this seems reasonable!

[nnarayen]

If we do decide to go with this approach, just FYI that we have to:

1. build new base images
2. update base version image tag