Build in docker

[javabrett]

This PR is related to the goals outlined in #17 - to get the image at https://hub.docker.com/r/messagebird/pushprom/ up-to-date and automatically building/pushing.

Here pushprom is built in an Alpine container, which is what the existing image uses. I had to set CGO_ENABLED=1 to get the build to work, which differs from the Makefile build. I ended-up adding a multi-stage build to slim-down the final image size.

Since this uses an in-container in-Alpine toolchain, it is likely that the resulting binary is linked differently - I don't know which toolchain was used to build the binary uploaded into the existing image.

If this approach works, it should allow the existing image (last pushed 2 years ago) to be flipped-over to an automated build.

[marcelcorso]

Hey Brett,

Thanks for the PR. We like it. The only thing now is that we moved to go modules and some of the code you did uses dep.

Sorry for the slow response.

[marcelcorso]

I just did this https://github.com/messagebird/pushprom/commit/03b73643a0ce824fc9c0ea3472645e5770eae6ce

to put out a fire and push a new version to docker hub. It's not great but it gets the job done.

If we automate the building on docker hub then we can revert this

[Juanadelacuesta]

Hi @javabrett This issue, the mod update and usage of a basic alpine image as base for the image are proposed in https://github.com/messagebird/pushprom/pull/23 take a look

[javabrett]

Thinking of closing this in favour of #23 and other changes ... but is the eventual goal to have Docker Hub automated builds from master and tags? Don’t yet have that, so changes aren’t immediately available in Docker.

[javabrett]

Going through very old notifications and PRs ... is there any value in this PR any more, resolving conflicts etc.?