Docker: adding a file from the parent directory

Question

In my Dockerfile , I have:

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

This file exists as ls ../../myapp.war returns the correct file to me, but when I execute sudo docker build -t myapp . , I have:

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

Does anyone know why and how to do it right?

Answer 1

You can create a Docker file from the parent directory:

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

Answer 2

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

From the documentation :

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

EDIT: Now there is an option ( -f ) to set the path to your Dockerfile; it can be used to achieve what you want, see @Boedy response nelow.

Answer 3

With docker-compose, you can set the context folder:

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

Answer 4

The solution for those using 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 you can play with volumes in the Dockerfile .

Answer 5

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

• Create a base image in the parent folder
• Added necessary files.
• This image is used as the base image for the project, which is located in the child folder.

The -f flag did not solve my problem, because my onbuild image onbuild looking for a file in the folder and had to call like this:

-f foo/bar/Dockerfile foo/bar

instead

-f foo/bar/Dockerfile .

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

Answer 6

Adding 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 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/ 

The command used to create the docker image

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