I'm trying to create a Dockerfile that copies all the files in the currently directory to a specific folder.
Currently I have
COPY . /this/folder
I'm unable to check the results of this command, as my container closes nearly immediately after I run it. Is there a better way to test if the command is working?
you can start a container and check.
$ docker run -ti --rm <DOCKER_IMAGE> sh
$ ls -l /this/folder
If your docker image has ENTRYPOINT setting, then run below command:
$ docker run -ti --rm --entrypoint sh <DOCKER_IMAGE>
$ ls -l /this/folder
If it is only for testing, include the below command in your docker file:
RUN cd /this/folder && ls
This will list the directory contents while docker build
Related
I am trying to bindmount a directory form docker container to my host directory called /home, the docker container directory which I am trying to sync is named as /test and it contains a file called new.txt.
My Dockerfile is in /home/sampledocker1 directory. Its contents are as follows:
FROM ubuntu:18.04
RUN ["/bin/bash", "-c", "mkdir test"]
COPY new.txt test
Here, local file new.txt available in current path.
I executed the below commands first I built the docker image and started the container as follows:
docker build -t sample1:latest . # image is created properly
docker run -t -d -v /home:/test sample1:latest /bin/bash
After creating container with mount option, I am expecting that the file new.txt in test folder of container would appear in my /home directory but it did not.
Here bindmount is not happening properly.
By running -v option you actually override directory that already exists in the docker file.
If you run:
docker run -ti sample1:latest /bin/bash
You will find /test/new.txt file because it is added to the image layer with COPY command on the Dockerfile.
If you run:
docker run -ti -v /home:/test sample1:latest /bin/bash
You will find the contents of your computers /home directory in the /test of the docker container, because -v (mouted volume) overrides original image layer created with the COPY command on the Dockerfile.
THE SUGGESTION: Remove both COPY and mkdir commands from your Dockerfile:
FROM ubuntu:18.04
# Nothing at all
And mount your current directory with your docker run command:
docker run -ti -v $(pwd):/test sample1:latest /bin/bash
Since your Dockerfile is empty, equivalent command is just running ubuntu:18:04 image:
docker run -ti -v $(pwd):/test ubuntu:18.04 /bin/bash
p.s. I changed -d (detached) to -i(interactive) on the example to make sure that you enter docker image as soon as you run docker run command.
So recently came across this weird case where I am trying to access file in my local dir into my container.
When I run the following command on terminal it runs fine and shows the expected list of file
docker run -it --rm -v $(pwd):/mnt/data -w /mnt/data-sink artprod.dev.abc.com/org/cli ls
But when I try to run this via makefile it shows nothing,(I run make in the same path where I run the docker cmd in the previous step)
docker-publish: build
echo "Publishing $(APP_NAME) snapshot $(VERSION)"
docker run -it --rm -v $(pwd):/mnt/data -w /mnt/data-sink artprod.dev.abc.com/org/cli ls
$(shell pwd) worked simply $(pwd) in make didnt do the shell interpolation.
I created a Docker like:
FROM rikorose/gcc-cmake
RUN git clone https://github.com/hect1995/UBIMET_Challenge.git
WORKDIR /UBIMET_Challenge
RUN mkdir build
WORKDIR build
#RUN apt-get update && apt-get -y install cmake=3.13.1-1ubuntu3 protobuf-compiler
RUN cmake ..
RUN make
Afterwards I do:
docker build --tag trial .
docker run -t -i trial /bin/bash
Then I run an executable that saves a .png file inside the container.
How can I visualize the image?
You can execute something inside the container.
To see all containers you can run docker ps --all.
To execute something inside container you can run docker exec <container id> command.
Otherwise you can copy files from container to host, with docker cp <container id>:/file-path ~/target/file-path
Please mount a localhost volume(directory) with container volume(directory) in where you are saving your images.
now all of your images saved in container directory will be available in host or localhost mount directory. From there you can visualize or download to another machine.
Please follow this
docker run --rm -d -v host_volume_or-directory:container_volume_direcotory trial
docker exec -it container_name /bin/bash
I would like to create a makefile that runs a docker container, automatically mount the current folder and within the container CD to the shared directory.
I currently have the following which runs the docker image and mounts the directory with no issue. But I am unsure how to get it to change directory.
run:
docker run --rm -it -v $(PWD):/projects dockerImage bash
I've seen some examples where you can append -c "cd /projects" at the end so that it is:
docker run --rm -it -v $(PWD):/projects dockerImage bash -c "cd /projects"
however it will immediately exit the bash command afterwards. Ive also seen an example where you can append && at the end so that it is the following:
docker run --rm -it -v $(PWD):/projects dockerImage bash -c "cd /projects &&".
Unfortunately the console will just hang.
You can specify the working directory in your docker run command with the -w option. So you can do something like this:
docker run --rm -it -v $(PWD):/projects -w /projects dockerImage bash
You can find this option in the official docs here https://docs.docker.com/engine/reference/run/.
I want to create docker volume and add directory and files into it without creating extra container/images or within minimal time. That thing would go into script, so interactions like -it bash won't do.
I can copy files with:
docker container create --name dummy -v myvolume:/root hello-world
docker cp c:\myfolder\myfile.txt dummy:/root/myfile.txt
docker rm dummy
How do I create an empty dir?:
attempt 1
mkdir lol; docker cp ./lol dummy:/root/lol # cannot copy directory
attempt 2
docker commit [CONTAINER_ID] temporary_image
docker run --entrypoint=bash -it temporary_image
This thing requires to pull image with bash.
this worked for me, you can try it out. I am doing the exact thing running from script
VOL_NAME=temp_vol
docker volume create $VOL_NAME
docker run -v $VOL_NAME:/root --name helper busybox true
mkdir tmp
docker cp tmp helper:/root/dir0
docker cp tmp helper:/root/dir1
docker cp tmp helper:/root/dir2
rm -rf tmp
docker rm helper
# check volume
sudo ls /var/lib/docker/volumes/$VOL_NAME/_data
dir0 dir1 dir2