Docker: adding a file from a parent directory

Question

In my Dockerfile I've got :

ADD ../../myapp.war /opt/tomcat7/webapps/

That file exists as ls ../../myapp.war returns me the correct file but when I execute sudo docker build -t myapp . I've got :

Step 1 : ADD ../../myapp.war /opt/tomcat7/webapps/
2014/07/02 19:18:09 ../../myapp.war: no such file or directory

Does somebody know why and how to do it correctly?

Answer 1

You can build the Dockerfile from the parent directory:

docker build -t <some tag> -f <dir/dir/Dockerfile> .

Answer 2

With docker-compose, you could set context folder:

#docker-compose.yml
version: '3.3'    
services:
      yourservice:
        build:
          context: ./
          dockerfile: ./docker/yourservice/Dockerfile

Answer 3

Unfortunately, (for practical and security reasons I guess), if you want to add/copy local content, it must be located under the same root path than the Dockerfile.

From the documentation:

The <src> path must be inside the context of the build; you cannot ADD ../something/something, because the first step of a docker build is to send the context directory (and subdirectories) to the docker daemon.

EDIT: There's now an option (-f) to set the path of your Dockerfile ; it can be used to achieve what you want, see @Boedy 's response.

Answer 4

Adding some code snippets to support the accepted answer.

Directory structure :

setup/
 |__docker/DockerFile
 |__target/scripts/<myscripts.sh>
src/
 |__<my source files>

Docker file entry:

RUN mkdir -p /home/vagrant/dockerws/chatServerInstaller/scripts/
RUN mkdir -p /home/vagrant/dockerws/chatServerInstaller/src/
WORKDIR /home/vagrant/dockerws/chatServerInstaller

#Copy all the required files from host's file system to the container file system.
COPY setup/target/scripts/install_x.sh scripts/
COPY setup/target/scripts/install_y.sh scripts/
COPY src/ src/

Command used to build the docker image

docker build -t test:latest -f setup/docker/Dockerfile .

Answer 5

Since -f caused another problem, I developed another solution.

• Create a base image in the parent folder
• Added the required files.
• Used this image as a base image for the project which in a descendant folder.

The -f flag does not solved my problem because my onbuild image looks for a file in a folder and had to call like this:

-f foo/bar/Dockerfile foo/bar

instead of

-f foo/bar/Dockerfile .

Also note that this is only solution for some cases as -f flag

Answer 6

The solution for those who use composer is to use a volume pointing to the parent folder:

#docker-composer.yml

foo:
  build: foo
  volumes:
    - ./:/src/:ro

But I'm pretty sure the can be done playing with volumes in Dockerfile.

Answer 7

If you are using skaffold, use 'context:' to specify context location for each image dockerfile - context: ../../../

            apiVersion: skaffold/v2beta4
            kind: Config
            metadata:
                name: frontend
            build:
                artifacts:
                    - image: nginx-angular-ui
                      context: ../../../
                      sync:
                          # A local build will update dist and sync it to the container
                          manual:
                              - src: './dist/apps'
                                dest: '/usr/share/nginx/html'
                      docker:
                          dockerfile: ./tools/pipelines/dockerfile/nginx.dev.dockerfile
                    - image: webapi/image
                      context: ../../../../api/
                      docker:
                          dockerfile: ./dockerfile
            deploy:
                kubectl:
                    manifests:
                        - ./.k8s/*.yml

skaffold run -f ./skaffold.yaml

Answer 8

• build the img from an upper dir

• name the img

• enable proper volume sharing

• check the Makefile in the link above on how-to start the container ...

  docker build . -t proj-devops-img --no-cache --build-arg UID=$(shell id -u) --build-arg GID=$(shell id -g) -f src/docker/devops/Dockerfile