How to install a specific package version in Alpine?

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I have a Dockerfile to build a Docker image that is based on Alpine Linux. Now I need to install a package as part of this Dockerfile.

Currently I have:

RUN apk update && \
    apk upgrade && \
    apk add git

Apparently this is a bad idea, as the result is non-deterministic. Instead, it depends on the point in time at which I build the image, which version of git is getting installed.

What is the correct way of doing this?

I guess that I have to tell updated, upgrade and add which versions to use, but how do I do this?

I have seen that apk supports pinning of repositories, but that is not what I want (at least I think so), because I do not want to pin a repository, but a package.

In other words: If git could be installed via npm, I’d be able to run:

npm install git@1.9.2

(or whatever version I want to have). What is the equivalent to this for Alpine Linux?

Answer

You can set “sticky” versions like this:

# Both are equal
apk add packagename=1.2.3-suffix
apk add 'packagename<1.2.3-suffix'

That will upgrade packages only until the specified version. You can then safely use …

apk upgrade

to upgrade all packages, while packages with versions will remain with their version. To set a minimum version just use …

apk add "packagename>1.2.3-suffix"

In case you can’t find a package, while you can see it in the UI for Alpine packages, update your sources/package database:

apk update

The package repository can be found here:

https://pkgs.alpinelinux.org/packages

Never pin packages from the “edge” branch of the alpine package repo, as these are in test and may be revoked. (At pkgs.alpinelinux.org/packages, click “edge” and change it to the alpine image version you use, and click “search” again.)

Additional info by cowlinator

Pinning a package to an exact version carries the risk that the package will be dropped from the repo, and your Dockerfile will fail to build in the future. The official recommendation can be read here, citation below.

Alternately, you could simply set a minimum package version instead of an exact version.

We don’t at the moment have resources to store all built packages indefinitely in our infra. Thus we currently keep only the latest for each stable branch, and has always been like that.

…

There has been discussion of keep all packages tagged as Alpine in the future. However, this is still “in-progress”. The official recommendation is to keep your own mirror / repository with all the specific package and their versions that you may want to use.

— Timo Teräs, @fabled (Alpine)

The complete Alpine Linux organisations repositories can be found on this self hosted GitLab instance.

Attribution
Source : Link , Question Author : Golo Roden , Answer Author : Community

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