After carrying out commands with "-c" option of bash, how can I make the terminal wait for input while preserving the environment?
Like CMD /K *** or pwsh -NoExit -Command ***.
From a comment by Cyrus:
You can achieve something similar by abusing the --rcfile option:
bash --rcfile <(echo "export PS1='> ' && ls")
From bash manpage:
--rcfile file
Execute commands from file instead of the system wide initialization file /etc/bash.bashrc and the standard personal initialization file ~/.bashrc if the shell is interactive
This is the answer I was looking for. Thank you!!
As an example of use, I use the following method to use the latest docker image with my preferred repository without building the image:
# Call bash in the container from bash
docker run --rm -it ubuntu:22.04 bash -c "bash --rcfile <(echo 'sed -i -E '\''s%^(deb(-src|)\s+)https?://(archive|security)\.ubuntu\.com/ubuntu/%\1http://mirrors.xtom.com/ubuntu/%'\'' /etc/apt/sources.list && apt update && FooBar=`date -uIs`')"
# ... from pwsh
docker run --rm -it ubuntu:22.04 bash -c "bash --rcfile <(echo 'sed -i -E '\''s%^(deb(-src|)\s+)https?://(archive|security)\.ubuntu\.com/ubuntu/%\1http://mirrors.xtom.com/ubuntu/%'\'' /etc/apt/sources.list && apt update && FooBar=``date -uIs``')"
# Call dash (BusyBox ash) in the container from bash
docker run --rm -it alpine:latest ash -c "ash -c 'export ENV=\$1;ash' -s <(echo 'sed -i -E '\''s%^https?://dl-cdn\.alpinelinux\.org/alpine/%https://ftp.udx.icscoe.jp/Linux/alpine/%'\'' /etc/apk/repositories && apk update && FooBar=`date -uIs`')"
# ... from pwsh
docker run --rm -it alpine:latest ash -c "ash -c 'export ENV=`$1;ash' -s <(echo 'sed -i -E '\''s%^https?://dl-cdn\.alpinelinux\.org/alpine/%https://ftp.udx.icscoe.jp/Linux/alpine/%'\'' /etc/apk/repositories && apk update && FooBar=``date -uIs``')"
Related
I'm trying to run a complete script while the ssh session is live instead of single commands.
Here is my current code:
sh "ssh -tt -o StrictHostKeyChecking=no ubuntu#IPV4_DNS uptime"
sh "ssh -v ubuntu#IPV4_DNS docker pull X:${BUILD_NUMBER}"
sh "ssh -v ubuntu#IPV4_DNS docker rm -f test"
sh "ssh -v ubuntu#IPV4_DNS docker run --name=test -d -p 3000:3000X:${BUILD_NUMBER}"
The desired code is something like this, but the following doesn't work:*
sh "ssh -tt -o StrictHostKeyChecking=no ubuntu#IPV4_DNS uptime"
sh ''' ssh -v ubuntu#IPV4_DNS docker pull X:${BUILD_NUMBER}
&& docker rm -f test && docker run --name=test -d -p 3000:3000X:${BUILD_NUMBER}
'''
ssh something here && something else && another one
runs something here in the ssh session, and something else and another one locally. You want to add quotes to pass the entire command line to ssh.
sh "ssh -tt -o StrictHostKeyChecking=no ubuntu#IPV4_DNS uptime"
sh """ssh -v ubuntu#IPV4_DNS 'docker pull X:${BUILD_NUMBER} &&
docker rm -f test &&
docker run --name=test -d -p "3000:3000X:${BUILD_NUMBER}"'
"""
I switched to triple double quotes instead of triple single quotes, assuming you want Jenkins to expand ${BUILD_NUMBER} for you.
The original question asked about Bash, but for the record, you are running sh here, not Bash. If you wanted to use Bash features in a Jenkinsfile, you can add a shebang #!/usr/bin/env bash or similar as the very first line of the command. But that's not necessary here; all these commands are simple and completely POSIX. (Maybe see also Difference between sh and bash)
How do I make this work?
[alan#stormfather-0be642-default-1 ~]$ kubectl exec -it my-pod-0 -- bash -c "/bin/bash && cd /tmp"
[root#my-pod-0 /]# pwd
/
Change directory first and then sh into it.
kubectl exec -it my-pod-0 -- bash -c "cd /tmp && /bin/bash"
Mohsin Amjad's answer is both simple and correct, if you are getting the
..."bash": executable file not found in $PATH...
error, this just means the container inside the pod does not have bash installed, instead try sh or other shells. I.e. something like:
kubectl exec -it my-pod-0 -- sh -c "cd /tmp && echo $0 $SHELL"
I am new to Docker. I found that we can set environment variables using the ENV instruction in the Dockerfile. But how does one set Bash aliases for long commands in Dockerfile?
Basically like you always do, by adding it to the user's .bashrc file:
FROM foo
RUN echo 'alias hi="echo hello"' >> ~/.bashrc
As usual this will only work for interactive shells:
docker build -t test .
docker run -it --rm --entrypoint /bin/bash test hi
/bin/bash: hi: No such file or directory
docker run -it --rm test bash
$ hi
hello
For non-interactive shells you should create a small script and put it in your path, i.e.:
RUN echo -e '#!/bin/bash\necho hello' > /usr/bin/hi && \
chmod +x /usr/bin/hi
If your alias uses parameters (ie. hi Jim -> hello Jim), just add "$#":
RUN echo -e '#!/bin/bash\necho hello "$#"' > /usr/bin/hi && \
chmod +x /usr/bin/hi
To create an alias of an existing command, might also use ln -s:
ln -s $(which <existing_command>) /usr/bin/<my_command>
If you want to use aliases just in Dockerfile, but not inside a container then the shortest way is the ENV declaration:
ENV update='apt-get update -qq'
ENV install='apt-get install -qq'
RUN $update && $install apt-utils \
curl \
gnupg \
python3.6
And for use in a container the way like already described:
RUN printf '#!/bin/bash \n $(which apt-get) install -qq $#' > /usr/bin/install
RUN chmod +x /usr/bin/install
Most of the time I use aliases just in the building stage and do not go inside containers, so the first example is quicker, clearer and simpler for every day use.
I just added this to my app.dockerfile file:
# Set up aliases
ADD ./bashrc_alias.sh /usr/sbin/bashrc_alias.sh
ADD ./initbash_profile.sh /usr/sbin/initbash_profile
RUN chmod +x /usr/sbin/initbash_profile
RUN /bin/bash -C "/usr/sbin/initbash_profile"
And inside the initbash_profile.sh file which just appends my custom aliases and no need to source the .bashrc file:
# Add the Bash aliases
cat /usr/sbin/bashrc_alias.sh >> ~/.bashrc
It worked a treat!
Another option is to just use the "docker exec -it <container-name> command" from outside the container and just use your own .bashrc or the .bash_profile file (what ever you prefer).
E.g.,
docker exec -it docker_app_1 bash
I think the easiest way would be to mount a file into your container containing your aliases, and then specify where Bash should find it:
docker run \
-it \
--rm \
-v ~/.bash_aliases:/tmp/.bash_aliases \
[image] \
/bin/bash --init-file /tmp/.bash_aliases
Sample usage:
echo 'alias what="echo it works"' > my_aliases
docker run -it --rm -v ~/my_aliases:/tmp/my_aliases ubuntu:18.04 /bin/bash --init-file /tmp/my_aliases
alias
Output:
alias what='echo it works'
what
Output:
it works
You can use ENTRYPOINT, but it will not work for aliases, in your Dockerfile:
ADD dev/entrypoint.sh /opt/entrypoint.sh
ENTRYPOINT ["/opt/entrypoint.sh"]
Your entrypoint.sh file:
#!/bin/bash
set -e
function dev_run()
{
}
export -f dev_run
exec "$#"
Here is a Bash function to have your aliases in every container you use interactively.
ducker_it() {
docker cp ~/bin/alias.sh "$1":/tmp
docker exec -it "$1" /bin/bash -c "[[ ! -f /tmp/alias.sh.done ]] \
&& [[ -w /root/.bashrc ]] \
&& cat /tmp/alias.sh >> /root/.bashrc \
&& touch /tmp/alias.sh.done"
docker exec -it "$1" /bin/bash
}
Required step before:
grep ^alias ~/.zshrc > ~/bin/alias.sh
Used some of the previous solutions, but the aliases are not recognised still.
I'm trying to set aliases and use them both within later Dockerfile steps and in the container at runtime.
RUN echo "alias model-downloader='python3 ${MODEL_DL_PATH}/downloader.py'" >> ~/.bash_aliases && \
echo "alias model-converter='python3 ${MODEL_DL_PATH}/converter.py'" >> ~/.bash_aliases && \
source ~/.bash_aliases
# Download the model
RUN model-downloader --name $MODEL_NAME -o $MODEL_DIR --precisions $MODEL_PRECISION;
The solution for me was to use ENV variables that held folder paths and then add the exact executable. I could have use ARG too, but for more of my scenarios I needed the aliases in both the build stage and later in the runtime.
I used the ENV variables in conjunction with a Bash script that runs once dependencies have ponged and sets the Bash source, sets some more env variables, and allows for further commands to pipe through.
#ErikDannenberg's answer did the trick, but in my case, some adjustments were needed.
It didn't work with aliases cause apparently there's an issue with interactive shells.
I reached for his second solution, but it still didn't really work. I checked existing shell scripts in my project and noticed the head comment (first line = #!/usr/bin/env sh) differs a bit from #!/usr/bin/bash. After changing it accordingly it started working for my t and tc "aliases", but I had to use the addendum to his second solution for getting tf to work.
Here's the complete Dockerfile
FROM php:8.1.1-fpm-alpine AS build
RUN apk update && apk add git
RUN curl -sS https://getcomposer.org/installer | php && mv composer.phar /usr/local/bin/composer
RUN apk add --no-cache $PHPIZE_DEPS \
&& pecl install xdebug \
&& docker-php-ext-enable xdebug \
&& touch /usr/local/etc/php/conf.d/99-xdebug.ini \
&& echo "xdebug.mode=coverage" >> /usr/local/etc/php/conf.d/99-xdebug.ini \
&& echo -e '#!/usr/bin/env sh\nphp artisan test' > /usr/bin/t \
&& chmod +x /usr/bin/t \
&& echo -e '#!/usr/bin/env sh\nphp artisan test --coverage' > /usr/bin/tc \
&& chmod +x /usr/bin/tc \
&& echo -e '#!/usr/bin/env sh\nphp artisan test --filter "$#"' > /usr/bin/tf \
&& chmod +x /usr/bin/tf
WORKDIR /var/www
I'm wanting to detect in "docker run" whether -ti has been passed to the entrypoint script.
docker run --help for -t -i
-i, --interactive=false Keep STDIN open even if not attached
-t, --tty=false Allocate a pseudo-TTY
I have tried the following but even when tested locally (not inside docker) it didn't work and printed out "Not interactive" always.
#!/bin/bash
[[ $- == *i* ]] && echo 'Interactive' || echo 'Not interactive'
entrypoint.sh:
#!/bin/bash
set -e
if [ -t 0 ] ; then
echo "(interactive shell)"
else
echo "(not interactive shell)"
fi
/bin/bash -c "$#"
Dockerfile:
FROM debian:7.8
COPY entrypoint.sh /usr/bin/entrypoint.sh
RUN chmod 755 /usr/bin/entrypoint.sh
ENTRYPOINT ["/usr/bin/entrypoint.sh"]
CMD ["/bin/bash"]
build the image:
$ docker build -t is_interactive .
run the image interactively:
$ docker run -ti --rm is_interactive "/bin/bash"
(interactive shell)
root#dd7dd9bf3f4e:/$ echo something
something
root#dd7dd9bf3f4e:/$ echo $HOME
/root
root#dd7dd9bf3f4e:/$ exit
exit
run the image not interactively:
$ docker run --rm is_interactive "echo \$HOME"
(not interactive shell)
/root
$
This stackoverflow answer helped me find [ -t 0 ].
This works:
# echo 1 and exit:
$ docker run -i -t image /bin/bash -c "echo 1"
1
# exit
# echo 1 and return shell in docker container:
$ docker run -i -t image /bin/bash -c "echo 1; /bin/bash"
1
root#4c064f2554de:/#
Question: How could I source a file into the shell? (this does not work)
$ docker run -i -t image /bin/bash -c "source <(curl -Ls git.io/apeepg) && /bin/bash"
# content from http://git.io/apeepg is sourced and shell is returned
root#4c064f2554de:/#
In my case, I use RUN source command (which will run using /bin/bash) in a Dockerfile to install nvm for node.js
Here is an example.
FROM ubuntu:14.04
RUN rm /bin/sh && ln -s /bin/bash /bin/sh
...
...
RUN source ~/.nvm/nvm.sh && nvm install 0.11.14
I wanted something similar, and expanding a bit on your idea, came up with the following:
docker run -ti --rm ubuntu \
bash -c 'exec /bin/bash --rcfile /dev/fd/1001 \
1002<&0 \
<<<$(echo PS1=it_worked: ) \
1001<&0 \
0<&1002'
--rcfile /dev/fd/1001 will use that file descriptor's contents instead of .bashrc
1002<&0 saves stdin
<<<$(echo PS1=it_worked: ) puts PS1=it_worked: on stdin
1001<&0 moves this stdin to fd 1001, which we use as rcfile
0<&1002 restores the stdin that we saved initially
You can use .bashrc in interactive containers:
RUN curl -O git.io/apeepg.sh && \
echo 'source apeepg.sh' >> ~/.bashrc
Then just run as usual with docker run -it --rm some/image bash.
Note that this will only work with interactive containers.
I don't think you can do this, at least not right now. What you could do is modify your image, and add the file you want to source, like so:
FROM image
ADD my-file /my-file
RUN ["source", "/my-file", "&&", "/bin/bash"]