docker: multi-stage builds (intermediate) anthony explains

today I talk about docker multi-stage builds -- why they're useful, and yet why I tend to avoid them!
- what is docker: • what is docker and how...
playlist: • anthony explains
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I won't ask for subscriptions / likes / comments in videos but it really helps the channel. If you have any suggestions or things you'd like to see please comment below!

[@putnam120]

I mostly use multistage builds for the security aspects. Most of my build require that I provide credentials to access external resources.
In these situations you don't want your credentials in the final image. Newer versions of docker have ways of passing in secrets. But our IT department refuses to update the version we use so multi state build it is

[@RuslanKovtun]

For me caching in multistage build works. As I have notices, you will have rebuilds of first stage where you have changes: e.g. if you cp reqeuests.txt that is different from what was before, all later layers will be rebuild, otherwise docker will check later commands to find changes if any. So, if you want to optimize build time, put things that will change frequenty to the end to cache more layers.

[@anthonywritescode]

yeah that's not really related to the multi stage problem. with multi stage it'll always rebuild unless you carefully cache all the intermediate builds

[@mishrasidhant]

Great explanation, thank you

[@Phaust94]

Your views are critically low for as good a channel you are! Thanks!

[@bakhtiyargarashov805]

Any logical use case of using multi-stage for Python apps ? I mean for languages like Go, C, Rust etc where you have build artifacts as a binary output it makes absolute sense to reduce image size

[@anthonywritescode]

same applies for python -- say you have to build one of your dependencies C extensions

[@hamidja1537]

Thanks for sharing

[@manuel56354]

Please explain Nix vs Docker, in terms of convenience for a long-term project which you want to always work, even if you build it 5-10 years later.

[@anthonywritescode]

easy: I would never use or suggest anyone use nix

[@manuel56354]

@@anthonywritescode That's interesting. I've been recently using it for a machine. It's hard to learn and apply. Updating dependencies is also a manual process. But the end result looks consistent and reproducible. What problems do you see in it?

[@Ownermode]

@@manuel56354 it is difficult to learn. Documentation is all over the place. So using Docker or podman you are assured that it will work and there is a large community to help you.

[@a_maxed_out_handle_of_30_chars]

thank you :)

[@samrybkin9184]

Dockerfile:
FROM ubuntu:jammy
RUN : \
&& apt-get update \
&& DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommend
gcc \
libc6-dev \
&& apt-get clean \
&& rm -rf /var/lib/apt/lists/*
COPY main.c .
RUN gcc -o /usr/local/bin/hello-hello-world main.c
Hi when I try to build image i recieve next error:
ERROR: failed to solve: dockerfile parse error on line 6: unknown instruction: gcc
Can you explain please what I am doing wrong ?
And if it not secret what keyboard model do you use ?

[@anthonywritescode]

you're missing a backslash after `--no-install-recommends`
there's an faq playlist you can click on my channel to learn about the keyboard (and more!)