I am following "Creating a Docker container action" and everything works great for me except that I would like to parametrize FROM field in my Dockerfile (I need to run CI tests against different versions of dependency, packaged as Docker image).
Ideally, in my Dockerfile, I'd like to use ARG or something something similar to:
ARG version=latest
FROM alpine:${version}
...
... but it is unclear how to pass build args.
Is there a way to something like this?
I have not found a good way to do this out of the box.
At the moment Docker container action
won't even let you to specify Dockerfile using arguments (through runs.image in action.yml).
The solution for me was using this action.
I tried running docker push command from the docker file but it throw an error
The command returned a non-zero code: 127
No there isn't. Dockerfile is an image build description format, it is not a general purpose scripting language.
Write a wrapper script if you need to do something that requires a scripting language.
No, these are completely different things: a Dockerfile just specifies the image you intend to build; what happens with the image after (e.g. uploading it into a repository) must be handled by something else (e.g. a script).
I used to list the tests directory in .dockerignore so that it wouldn't get included in the image, which I used to run a web service.
Now I'm trying to use Docker to run my unit tests, and in this case I want the tests directory included.
I've checked docker build -h and found no option related.
How can I do this?
Docker 19.03 shipped a solution for this.
The Docker client tries to load <dockerfile-name>.dockerignore first and then falls back to .dockerignore if it can't be found. So docker build -f Dockerfile.foo . first tries to load Dockerfile.foo.dockerignore.
Setting the DOCKER_BUILDKIT=1 environment variable is currently required to use this feature. This flag can be used with docker compose since 1.25.0-rc3 by also specifying COMPOSE_DOCKER_CLI_BUILD=1.
See also comment0, comment1, comment2
from Mugen comment, please note
the custom dockerignore should be in the same directory as the Dockerfile and not in root context directory like the original .dockerignore
i.e.
when calling
DOCKER_BUILDKIT=1
docker build -f /path/to/custom.Dockerfile ...
your .dockerignore file should be at
/path/to/custom.Dockerfile.dockerignore
At the moment, there is no way to do this. There is a lengthy discussion about adding an --ignore flag to Docker to provide the ignore file to use - please see here.
The options you have at the moment are mostly ugly:
Split your project into subdirectories that each have their own Dockerfile and .dockerignore, which might not work in your case.
Create a script that copies the relevant files into a temporary directory and run the Docker build there.
Adding the cleaned tests as a volume mount to the container could be an option here. After you build the image, if running it for testing, mount the source code containing the tests on top of the cleaned up code.
services:
tests:
image: my-clean-image
volumes:
- '../app:/opt/app' # Add removed tests
I've tried activating the DOCKER_BUILDKIT as suggested by #thisismydesign, but I ran into other problems (outside the scope of this question).
As an alternative, I'm creating an intermediary tar by using the -T flag which takes a txt file containing the files to be included in my tar, so it's not so different than a whitelist .dockerignore.
I export this tar and pipe it to the docker build command, and specify my docker file, which can live anywhere in my file hierarchy. In the end it looks like this:
tar -czh -T files-to-include.txt | docker build -f path/to/Dockerfile -
Another option is to have a further build process that includes the tests. The way I do it is this:
If the tests are unit tests then I create a new Docker image that is derived from the main project image; I just stick a FROM at the top, and then ADD the tests, plus any required tools (in my case, mocha, chai and so on). This new 'testing' image now contains both the tests and the original source to be tested. It can then simply be run as is or it can be run in 'watch mode' with volumes mapped to your source and test directories on the host.
If the tests are integration tests--for example the primary image might be a GraphQL server--then the image I create is self-contained, i.e., is not derived from the primary image (it still contains the tests and tools, of course). My tests use environment variables to tell them where to find the endpoint that needs testing, and it's easy enough to get Docker Compose to bring up both a container using the primary image, and another container using the integration testing image, and set the environment variables so that the test suite knows what to test.
Sadly it isn't currently possible to point to a specific file to use for .dockerignore, so we generate it in our build script based on the target/platform/image. As a docker enthusiast it's a sad and embarrassing workaround.
I am trying to dockerize the go package that I found here...
https://github.com/siddontang/go-mysql-elasticsearch
The docker image is much more convenient than installing go on all the servers. But the following dockerfile is not working.
FROM golang:1.6-onbuild
RUN go get github.com/siddontang/go-mysql-elasticsearch
RUN cd $GOPATH/src/github.com/siddontang/go-mysql-elasticsearch
RUN make
RUN ./bin/go-mysql-elasticsearch -config=./etc/river.toml
How do I build a go package directly from github using a concise dockerfile?
Update
https://hub.docker.com/r/eaglechen/go-mysql-elasticsearch/
I found the exact dockerfile that would do this. But the docker command mentioned on that page does not work. It does not start the go package nor does it start the container.
It depends on what you mean by "not working", but RUN ./bin/... means RUN from the current working directory (/go/src/app in golang/1.6/onbuild/Dockerfile).
And go build in Makefile would put the binary in
$GOPATH/src/github.com/siddontang/go-mysql-elasticsearch/bin/...
So you need to add to your Dockerfile:
WORKDIR $GOPATH/src/github.com/siddontang/go-mysql-elasticsearch
I guess this should do what I am looking for.
https://github.com/EagleChen/docker_go_mysql_elasticsearch
And I hope one day I will learn to use that little search box.
From the following image: https://registry.hub.docker.com/u/cloudesire/activemq/dockerfile/
If I wanted to override the ACTIVEMQ_VERSION environment variable in my child docker file, I assumed I would be able to do something like the following:
FROM cloudesire/activemq:latest
MAINTAINER abc <abc#xyz.co.uk>
ENV ACTIVEMQ_VERSION 5.9.1
ADD ./src/main/resources/* /opt/activemq/conf/
However this does not seem to work. Admittedly I am new to Docker and have obviously misunderstood something. Please could someone explain why this does not work, and how/if I can achieve it another way?
That won't work. The ACTIVEMQ_VERSION has already been used by the cloudesire/activemq:latest image build to populate its image layers. All the ActiveMQ installation files based on version 5.11.1 are already extracted in their corresponding directories.
In your Dockerfile you only can build on top of what has already been build there and add your files. Your own Dockerfile build will not re-run the build instructions described in their Dockerfile.
If you need to have your own cloudesire/activemq image based on version 5.9.1 you need to clone their Dockerfile, adjust the version there and build it locally. So you could base your other Dockerfile on it.