Dockerfile for seqcli on Alpine Linux

[mloskot]

Following up datalust/seqcli#116 (comment), thought I'll share complete sample of my very simple Dockerfile to build container image based on Alpine Linux with installed latest seqcli:

FROM alpine:3

RUN <<EOF
  apk --no-cache add icu-libs
  VERSION=$(wget -qO- "https://api.github.com/repos/datalust/seqcli/releases/latest" | grep -E '"tag_name":\s*"v?([0-9.]+)' | sed -E "s/.*v([0-9.]+).+/\\1/")
  wget -O /tmp/seqcli.tar.gz "https://github.com/datalust/seqcli/releases/download/v${VERSION}/seqcli-${VERSION}-linux-musl-x64.tar.gz"
  mkdir /opt/seqcli
  tar -xzf /tmp/seqcli.tar.gz --directory /opt/seqcli --strip-components=1
  rm /tmp/seqcli.tar.gz
  ln -s /opt/seqcli/seqcli /usr/local/bin/seqcli
EOF

ENTRYPOINT ["/opt/seqcli/seqcli"]

It works the same way as the official datalust/seqcli:

$ docker run --rm seqcli:latest version
2025.2.02423+5a12d363d6515a928b0a0885c115936383e6b453

Currently, the official datalust/seqcli images are based on the Ubuntu 22.04, but there may be users who prefer Alpine or prefer much smaller image:

$ docker image ls | grep seqcli
seqcli                        latest    d0ee4fc6bc22   39 minutes ago   128MB
datalust/seqcli               latest    98c45e17ae2b   4 days ago       217MB

[nblumhardt]

Thanks @mloskot 👍

There probably aren't significant advantages to us sticking with Ubuntu for the base image; the original choice was driven by broad support from .NET and everything else, but that was quite a few years ago and is no longer a concern.

The only compatibility edge case we've come up with so far, for people updating between seqcli image versions, is if the container's used for hosting Seq apps seqcli app run, and the app itself relies on distro-specific features.

It looks like trusting additional CA certs uses the same tooling on Alpine as on Ubuntu, which would otherwise be another compatibility consideration.

Any others spring to mind? If not, we might look at basing the 2026.x image on Alpine and save everyone some disk space/bandwidth.

[mloskot]

Hi @nblumhardt, nothing comes to mind in terms of any compatibility issues, but if I encounter any, I'll share it.

The list of seqcli commands I've run in the Alpine-based container is still modest so far - version log, config, apikey *-s with create in two authentication modes, --connect-password-stdin and --apikey - but I'm not done yet :)

The official switch from Ubuntu to Alpine would likely benefit from thorough testing of the container image.