Docker automated build fails after change to alpine base image

[haxorof]

After change to alpine:3.5 it seems the build at Docker fails.
https://hub.docker.com/r/dbhi/prometheus-sql/builds/

Reason for this is that in the golang base image everything was built during container creation. However there is a golang:alpine base image which might be possible to use that would be smaller than the golang:onbuild which might be something to try.

[haxorof]

Compared the sizes between building a container of prometheus-sql as it is right now and compared that to golang:alpine.

dbhi/prometheus-sql:latest = 11.8M
             golang:alpine = 267.2M

Size difference is quite significant. So looking into options like publish releases here in Github and then use wget/curl to get those when the automated build process is started for Docker hub.

@bruth When is the automated build triggered at Docker Hub? Or is manually triggered?

[haxorof]

After some testing it seems prometheus-sql won't run in the alpine container probably because Alpine uses musl libc instead of glibc. However using a different base image like frolvlad/alpine-glibc:alpine-3.5 will make it work.

So if we publish a release here on Github for prometheus-sql then the Dockerfile could be something like this:

FROM frolvlad/alpine-glibc:alpine-3.5

ARG PROMETHEUS_SQL_VERSION=0.1.0
ARG BASE_URL=https://github.com/chop-dbhi/prometheus-sql/releases/download/$PROMETHEUS_SQL_VERSION
ARG OS_ARCH=linux-amd64
ARG ZIP_FILE=prometheus-sql-${OS_ARCH}.zip

ADD $BASE_URL/$ZIP_FILE /tmp/
RUN unzip /tmp/$ZIP_FILE -d /tmp \
  && cp /tmp/$OS_ARCH/* /usr/local/bin/ \
  && rm -rf /tmp/*

EXPOSE 8080

ENTRYPOINT ["/usr/local/bin/prometheus-sql", "-host", "0.0.0.0"]

# Default command assumes the SQL agent is linked.
CMD ["-service", "http://sqlagent:5000"]

@bruth What do you think about this?

[bruth]

@haxorof So it was automated before, but I only recently switched to a manual build (120c2f5) once I realized how big the image was. That 11.8 megs is because I cross-compiled locally and packaged it up into an alpine image.

After some testing it seems prometheus-sql won't run in the alpine container probably because Alpine uses musl libc instead of glibc.

Bah, i've run into that quite a few times. Your solution is pretty slick, I never thought about that approach, but looks great for continuing to use automated builds.

[haxorof]

Thanks! I will do some additional tests and later do a commit with a new Docker file. Shall see what is possible to do regarding releases here on Github to make it as easy and smooth as possible. I have used it in my own little repo before but never together with a automated Docker build.

@bruth If you turn on automatic builds again will it then start building upon commit?

[bruth]

Yes. I just turned it back on.