Setting locale inside docker container - docker

My container has locale settep up to POSIX and I want to change it. After I do that, I exit and reenter the container and the locale is back to POSIX.
I don't want to build a new image or run a new container because we have a lot of containers in several machines.
Running this:
DEBIAN_FRONTEND=noninteractive apt-get install -y locales
sed -i -e 's/# pt_PT ISO-8859-1/pt_PT ISO-8859-1/' /etc/locale.gen
dpkg-reconfigure --frontend=noninteractive locales
export LANGUAGE=pt_PT
export LANG=pt_PT
export LC_ALL=pt_PT
Works great in running container but exiting and reentering the container makes the changes lost.
Already tried this code in container Entrypoint but the export doesn't have any effect.

Those settings are shell-session bound, not OS-bound. To make it OS-bound, you should write it in OS files, but when the service restarts it will apply the image without those changes.
So, that has to be set in Dockerfile, to be image-bound, something like:
RUN DEBIAN_FRONTEND=noninteractive apt-get install -y locales && \
sed -i -e 's/# pt_PT ISO-8859-1/pt_PT ISO-8859-1/' /etc/locale.gen && \
dpkg-reconfigure --frontend=noninteractive locales
ENV LANG pt_PT
ENV LANGUAGE pt_PT
ENV LC_ALL pt_PT

changes can't be stored in the container. I think the best way is to commit your changes into the container and create a new one.
you can use "docker commit" for this purpose.
docker commit
Ref: https://docs.docker.com/engine/reference/commandline/commit/

Related

docker can't run vscodium

Mine is a bit of a peculiar situation, I created a dockerfile that "works" if not for some proiblems,
Here is a "working" version:
ARG IMGVERS=latest
FROM bensuperpc/tinycore:${IMGVERS}
LABEL maintainer "Vinnie Costante <****#gmail.com>"
ARG DOWNDIR=/tmp/download
ARG INSTDIR=/opt/vscodium
ARG REPOAPI="https://api.github.com/repos/VSCodium/vscodium/releases/latest"
ENV LANG=C.UTF-8 LC_ALL=C PATH="${PATH}:${INSTDIR}/bin/"
RUN tce-load -wic Xlibs nss gtk3 libasound libcups python3.9 tk8.6 \
&& rm -rf /tmp/tce/optional/*
RUN sudo ln -s /lib /lib64 \
&& sudo ln -s /usr/local/etc/fonts /etc/fonts \
&& sudo mkdir -p ${DOWNDIR} ${INSTDIR} \
&& sudo chown -R tc:staff ${DOWNDIR} ${INSTDIR}
#COPY VSCodium-linux-x64-1.57.1.tar.gz ${DOWNDIR}/
RUN wget http://192.168.43.6:8000/VSCodium-linux-x64-1.57.1.tar.gz -P ${DOWNDIR}
RUN tar xvf ${DOWNDIR}/VSCodium*.gz -C ${INSTDIR} \
&& rm -rf ${DOWNDIR}
CMD ["codium"]
The issues are these:
Starting the image with this command vscodium does not start, but entering the shell (adding /bin/ash to the end of the docker run) and then running codium instead vscodium starts. I tried many ways, even changing the entrypoint, the result is always the same. But if I try to add any other graphic program (like firefox) and replace the argument of the CMD instruction inside the dockerfile, everything works as it should.
docker run -it --rm \
--net=host \
--env="DISPLAY=unix${DISPLAY}" \
--workdir /home/tc \
--volume="$HOME/.Xauthority:/root/.Xauthority:rw" \
--name tc \
tinycodium
the last two versions of codium (1.58.0 and 1.58.1) don't work at all on docker but they start normally on the same distro not containerized. I tried installing other dependencies but nothing worked. Right now I don't know how to understand what's wrong with these two new versions.
I don't know how to set a volume to save codium data, I tried something like this --volume=/home/vinnie/docker:/home/tc but there are always problems with user/group permissions. I've also tried booting the container as user by adding it to the docker group but there's always a mess with permissions. If someone could explain me how to proceed, the directories I want to save are these:
/home/tc/.vscode-oss
/home/tc/.cache/mesa_shader_cache
/home/tc/.config/VSCodium
/home/tc/.config/glib-2.0/settings
/home/tc/.local/share
Try running codium --verbose and see if the container starts

CircleCI using docker node:8 (debian) does not set up proper locale

I have CircleCI pipeline setup for my test flow using Jest snapshot and one of my snapshot tests keeps failing. I use Javascript to generate a Date object (new Date("YYYY-MM-DD")) and locally it yields MM/DD/YYYY but in the docker image (node:8) it yields YYYY-MM-DD instead so the snapshot test fails. I have tried to set up locales by:
docker:
- image: circleci/node:8
environment:
TZ: "America/Los_Angeles"
LANG: en_US.UTF-8
LANGUAGE: en_US.UTF-8
LC_ALL: en_US.UTF-8
But it complains it cannot set the default locale so I added:
- run:
name: Reconfigure Locale
command: sudo dpkg-reconfigure locales
which seemed to be a solution for most of the people that had the same problem but not my case.
I also tried to have the same local docker image and test it there and it worked fine with these commands:
RUN apt-get update && DEBIAN_FRONTEND=noninteractive apt-get install -y locales
RUN sed -i -e 's/# en_US.UTF-8 UTF-8/en_US.UTF-8 UTF-8/' /etc/locale.gen && \
dpkg-reconfigure --frontend=noninteractive locales && \
update-locale LANG=en_US.UTF-8
So I tried these in circleci and sed commands complained about permissions even when it is called with sudo.
Okay just FYI, it was the node version caused the date format issue. I installed full-icu npm package which handles locale for the node application. To re-visit my problem, I had successfully installed locale and set it to be the same as the local machine but Node won't pick the locale from the system but from the browser being used. I hope this info helps.

Docker file owners and groups

I think I have a dilemma. I am trying to create a Dockerfile to reproduce a long and complicated installation process (of ROS) so that my students can get it running with less headache.
I am combining various scripts provided with manual steps that are documented. The manual steps often say to do "sudo" but I am told that doing sudo inside a Dockerfile is to be avoided. So I move those steps to before the USER command in the Dockerfile because I am told that those commands run as root. However as a result the files and directories created are owned by root and I believe subsequent steps are failing.
I have two choices I think: move the commands to after the USER command and include sudo or try to make the install scripts create directories and files of the right ownership. Of course a priori I dont know what files and directories are going to be created.
Here is my Dockerfile (actually one of many I have been experimenting with.) Also if you see any other things that need to be improved or fixed please let me know!
FROM ubuntu:16.04
# create non-root user
ENV USERNAME ros
RUN adduser --ingroup sudo --disabled-password --gecos "" --shell /bin/bash --home /home/$USERNAME $USERNAME
RUN bash -c 'echo $USERNAME:ros | chpasswd'
ENV HOME /home/$USERNAME
RUN apt-get update && apt-get install --assume-yes wget sudo && \
wget https://raw.githubusercontent.com/ROBOTIS-GIT/robotis_tools/master/install_ros_kinetic.sh && \
chmod 755 ./install_ros_kinetic.sh && \
bash ./install_ros_kinetic.sh
RUN apt-get install --assume-yes ros-kinetic-joy ros-kinetic-teleop-twist-joy ros-kinetic-teleop-twist-keyboard ros-kinetic-laser-proc ros-kinetic-rgbd-launch ros-kinetic-depthimage-to-laserscan ros-kinetic-rosserial-arduino ros-kinetic-rosserial-python ros-kinetic-rosserial-server ros-kinetic-rosserial-client ros-kinetic-rosserial-msgs ros-kinetic-amcl ros-kinetic-map-server ros-kinetic-move-base ros-kinetic-urdf ros-kinetic-xacro ros-kinetic-compressed-image-transport ros-kinetic-rqt-image-view ros-kinetic-gmapping ros-kinetic-navigation ros-kinetic-interactive-markers
USER $USERNAME
WORKDIR /home/$USERNAME
RUN cd /home/$USERNAME/catkin_ws/src/ && \
git clone https://github.com/ROBOTIS-GIT/turtlebot3_msgs.git && \
git clone https://github.com/ROBOTIS-GIT/turtlebot3.git && \
git clone https://github.com/ROBOTIS-GIT/turtlebot3_simulations.git
# add catkin env
RUN echo 'source /opt/ros/kinetic/setup.bash' >> /home/$USERNAME/.bashrc
RUN echo 'source /home/ros/catkin_ws/devel/setup.bash' >> /home/$USERNAME/.bashrc
# RUN . /home/ros/.bashrc && \
# cd /home/$USERNAME/catkin_ws && \
# catkin_make
USER $USERNAME
ENTRYPOINT /bin/bash
Would be interesting for my own information to get why sudo should be avoided in containers.
Historically we use docker to automate build, test and deploy processes in our team and always tried to write Dockerfiles as close as possible to original process.
Lets say if you build in your host some app and launch some commands with sudo, some without, we managed to create exactly the same Dockerfiles. The positive feedback from this is that you are not obligated to write readme's on how to build the code anymore - you just supply Dockerfile and whenever someone wants to repeat all steps in non-container environment, he just follows (copy/pastes) commands from the file.
So my proposal is - in Dockerfile install packages first, then switch to user and proceed with all remaining steps, using sudo when necessary. You will have all artifacts owned by the user, not root.
UPD
Got the original discussion and this one. So it sounds like you choose the best approach based on your particular case and needs.

How to change locale settings on Fedora Docker container?

On a normal server e.g. a Linode VPS I would normally do:
localectl set-locale LANG=<locale>.utf8
timedatectl set-timezone <timezone>
But since systemd is not present or does not work on containers I get:
Failed to create bus connection: No such file or directory
Now, my goal is just to change these settings without using systemd but such approach seems to go undocumented. Is there a reference for non-systemd alternatives to config tools?
Some documentation about locale setting in arch wiki: https://wiki.archlinux.org/index.php/locale
In Dockerfile, adjust LANG to your desired locale. You can add more than one locale in /etc/locale.gen to have a choice later.
Works on debian, arch, but locale-gen misses on fedora:
ENV LANG=en_US.utf8
RUN echo "$LANG UTF-8" >> /etc/locale.gen
RUN locale-gen
RUN update-locale --reset LANG=$LANG
More general is localedef, works on fedora, too:
ENV LANG=en_US.UTF-8
localedef --verbose --force -i en_US -f UTF-8 en_US.UTF-8
Put this in your Dockerfile
ENV TZ=America/Denver
RUN ln -snf /usr/share/zoneinfo/$TZ /etc/localtime && echo $TZ > /etc/timezone
Edit .bash_profile or .bashrc from root and add the following.
TZ='Asia/Kolkata'
export TZ
Save file and commit image after its done.
Based on a technique used in sti-base, I came up with the following workaround for https://github.com/ncoghlan/fedbuildenv/blob/09a18d91e7af64a45394669bac2595a4b628960d/Dockerfile#L26:
# Set a useful default locale
RUN echo "export LANG=en_US.utf-8" > /opt/export_LANG.sh
ENV BASH_ENV=/opt/export_LANG.sh \
ENV=/opt/export_LANG.sh \
PROMPT_COMMAND="source /opt/export_LANG.sh"
BASH_ENV covers non-interactive bash sessions, ENV covers sh sessions, and PROMPT_COMMAND covers interactive bash sessions.
this seems to be the debians's equivalent of locale-gen:
RUN localedef -v -c -i fr_FR -f UTF-8 fr_FR.UTF-8 || true

ARG or ENV, which one to use in this case?

This could be maybe a trivial question but reading docs for ARG and ENV doesn't put things clear to me.
I am building a PHP-FPM container and I want to give the ability for enable/disable some extensions on user needs.
Would be great if this could be done in the Dockerfile by adding conditionals and passing flags on the build command perhaps but AFAIK is not supported.
In my case and my personal approach is to run a small script when container starts, something like the following:
#!/bin/sh
set -e
RESTART="false"
# This script will be placed in /config/init/ and run when container starts.
if [ "$INSTALL_XDEBUG" == "true" ]; then
printf "\nInstalling Xdebug ...\n"
yum install -y php71-php-pecl-xdebug
RESTART="true"
fi
...
if [ "$RESTART" == "true" ]; then
printf "\nRestarting php-fpm ...\n"
supervisorctl restart php-fpm
fi
exec "$#"
This is how my Dockerfile looks like:
FROM reynierpm/centos7-supervisor
ENV TERM=xterm \
PATH="/root/.composer/vendor/bin:${PATH}" \
INSTALL_COMPOSER="false" \
COMPOSER_ALLOW_SUPERUSER=1 \
COMPOSER_ALLOW_XDEBUG=1 \
COMPOSER_DISABLE_XDEBUG_WARN=1 \
COMPOSER_HOME="/root/.composer" \
COMPOSER_CACHE_DIR="/root/.composer/cache" \
SYMFONY_INSTALLER="false" \
SYMFONY_PROJECT="false" \
INSTALL_XDEBUG="false" \
INSTALL_MONGO="false" \
INSTALL_REDIS="false" \
INSTALL_HTTP_REQUEST="false" \
INSTALL_UPLOAD_PROGRESS="false" \
INSTALL_XATTR="false"
RUN yum install -y https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm \
https://rpms.remirepo.net/enterprise/remi-release-7.rpm
RUN yum install -y \
yum-utils \
git \
zip \
unzip \
nano \
wget \
php71-php-fpm \
php71-php-cli \
php71-php-common \
php71-php-gd \
php71-php-intl \
php71-php-json \
php71-php-mbstring \
php71-php-mcrypt \
php71-php-mysqlnd \
php71-php-pdo \
php71-php-pear \
php71-php-xml \
php71-pecl-apcu \
php71-php-pecl-apfd \
php71-php-pecl-memcache \
php71-php-pecl-memcached \
php71-php-pecl-zip && \
yum clean all && rm -rf /tmp/yum*
RUN ln -sfF /opt/remi/php71/enable /etc/profile.d/php71-paths.sh && \
ln -sfF /opt/remi/php71/root/usr/bin/{pear,pecl,phar,php,php-cgi,phpize} /usr/local/bin/. && \
mv -f /etc/opt/remi/php71/php.ini /etc/php.ini && \
ln -s /etc/php.ini /etc/opt/remi/php71/php.ini && \
rm -rf /etc/php.d && \
mv /etc/opt/remi/php71/php.d /etc/. && \
ln -s /etc/php.d /etc/opt/remi/php71/php.d
COPY container-files /
RUN chmod +x /config/bootstrap.sh
WORKDIR /data/www
EXPOSE 9001
Currently this is working but ... If I want to add let's say 20 (a random number) of extensions or any other feature that can be enable|disable then I will end with 20 non necessary ENV (because Dockerfile doesn't support .env files) definition whose only purpose would be set this flag for let the script knows what to do then ...
Is this the right way to do it?
Should I use ENV for this purpose?
I am open to ideas if you have a different approach for achieve this please let me know about it
From Dockerfile reference:
The ARG instruction defines a variable that users can pass at build-time to the builder with the docker build command using the --build-arg <varname>=<value> flag.
The ENV instruction sets the environment variable <key> to the value <value>.
The environment variables set using ENV will persist when a container is run from the resulting image.
So if you need build-time customization, ARG is your best choice.
If you need run-time customization (to run the same image with different settings), ENV is well-suited.
If I want to add let's say 20 (a random number) of extensions or any other feature that can be enable|disable
Given the number of combinations involved, using ENV to set those features at runtime is best here.
But you can combine both by:
building an image with a specific ARG
using that ARG as an ENV
That is, with a Dockerfile including:
ARG var
ENV var=${var}
You can then either build an image with a specific var value at build-time (docker build --build-arg var=xxx), or run a container with a specific runtime value (docker run -e var=yyy)
So if want to set the value of an environment variable to something different for every build then we can pass these values during build time and we don't need to change our docker file every time.
While ENV, once set cannot be overwritten through command line values. So, if we want to have our environment variable to have different values for different builds then we could use ARG and set default values in our docker file. And when we want to overwrite these values then we can do so using --build-args at every build without changing our docker file.
For more details, you can refer this.
Why to use ARG or ENV ?
Let's say we have a jar file and we want to make a docker image of it. So, we can ship it to any docker engine.
We can write a Dockerfile.
Dockerfile
FROM eclipse-temurin:17-jdk-alpine
VOLUME /tmp
ARG JAR_FILE
COPY ${JAR_FILE} app.jar
ENTRYPOINT ["java","-jar","/app.jar"]
Now, if we want to build the docker image using Maven, we can pass the JAR_FILE using the --build-arg as target/*.jar
docker build --build-arg JAR_FILE=target/*.jar -t myorg/myapp
However, if we are using Gradle; the above command doesn't work and we've to pass a different path: build/libs/
docker build --build-arg JAR_FILE=build/libs/*.jar -t myorg/myapp .
Once you have chosen a build system, we don’t need the ARG. We can hard code the JAR location.
For Maven, that would be as follows:
Dockerfile
FROM eclipse-temurin:17-jdk-alpine
VOLUME /tmp
COPY target/*.jar app.jar
ENTRYPOINT ["java","-jar","/app.jar"]
here, we can build an image with the following command:
docker build -t image:tag .
When to use `ENV`?
If we want to set some values at running containers and reflect that to the image like the Port Number that your application can run/listen on. We can set that using the ENV.
Both ARG and ENV seem very similar. Both can be accessed from within our Dockerfile commands in the same manner.
Example:
ARG VAR_A 5
ENV VAR_B 6
RUN echo $VAR_A
RUN echo $VAR_B
Personal Option!
There is a tradeoff between choosing ARG over ENV. If you choose ARG you can't change it later during the run. However, if you chose ENV you can modify the value at the container.
I personally prefer ARG over ENV wherever I can, like,
In the above Example:
I have used ARG as the build system maven or Gradle impacts during build rather than runtime. It thus encapsulates a lot of details and provided a minimum set of arguments for the runtime.
For more details, you can refer to this.

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