We Keep Coding

Syntax error: "(" unexpected when running Docker container

This is my Dockerfile:
# Setup Inst
FROM ubuntu:latest
MAINTAINER test
LABEL maintainer="test"
RUN mkdir /srv/papermc
WORKDIR /srv/papermc
# Install OpenJDK-17
RUN apt-get update && \
apt-get install -y openjdk-17-jre-headless && \
apt-get install -y ant && \
apt-get install -y screen && \
apt-get install -y wget && \
apt-get clean;
# Fix certificate issues
RUN apt-get update && \
apt-get install ca-certificates-java && \
apt-get clean && \
update-ca-certificates -f;
# Setup JAVA_HOME -- useful for docker commandline
ENV JAVA_HOME /usr/lib/jvm/java-17-openjdk-amd64/
RUN export JAVA_HOME
# Download PAPERMINECRAFT
RUN wget https://api.papermc.io/v2/projects/paper/versions/1.19.3/builds/363/downloads/paper-1.19.3-363.jar
# STOP
STOPSIGNAL SIGTERM
# ENV
ENV TYPE=VANILLA VERSION=1.19.3 EULA="" UID=1000 GID=1000 RCON_PASSWORD=paper
# Prepare RUN
EXPOSE 25565 25575
VOLUME /srv/papermc
RUN echo "screen -AmdS minecraft java -Xms1024M -Xmx1024M -jar /srv/mcvanilla/paper-1.19.2-220.jar nogui" > start
RUN chmod -R 775 /srv/papermc
ENTRYPOINT ["/bin/sh"]
CMD start
HEALTHCHECK none
It is building without errors, but if I try to start the container, I get the following error:
Successfully tagged papermc:latest
root#docker3:~# docker run papermc
/bin/sh: 2: Syntax error: "(" unexpected
I was expecting a Java error because of not accepting the EULA, but not this one. What could be wrong?

Your ENTRYPOINT/CMD setup is wrong. You should simplify the end of the file to
# ...do the installation steps...
ENV TYPE=VANILLA VERSION=1.19.3 EULA="" UID=1000 GID=1000 RCON_PASSWORD=paper
CMD java -Xms1024M -Xmx1024M -jar /srv/mcvanilla/paper-1.19.2-220.jar nogui
and then docker run papermc will start the server without requiring you to log in, start a screen session, or anything else.
As #CharlesDuffy hints in a comment, if you're just wrapping a single process, Docker and Screen have some similarities and it's unusual to use Screen in a container. You can view the docker logs of the container and, in the unusual event you need to interact with the process's stdin, docker attach to it.
What's actually happening in your case deals with the way string-form CMD is converted to an actual command-word array and then combined with ENTRYPOINT. The documentation on Dockerfile ENTRYPOINT has details on these mechanics. As you've written it, the single command the container runs is
/bin/sh /bin/sh -c 'start'
which in turn causes the shell to try to execute the /bin/sh binary as a shell script, passing it arguments -c and start as the positional variables $1 and $2. When /bin/sh is an ELF binary and not itself a shell script, you get a parse error like this.

Update gitlab JDK to JDK17 (VM doesn't have internet connection)

I am using Gitlab to build a Java tool using ant
The tool requires JDK 17, but ant JDK version is 11, and I'm trying to change it.
So I tried a lot of solutions using a remote repository or remote download site, but after some tries I found out that the VM used to build the tool is not connected to internet (trying to ping google or my IP address doesn't work).
So I tried to upload in the same package with the tool source code the JDK 17 (openjdk-17_linux-x64_bin.tar.gz) and install it there.
Here is the problem, I am not sure how to do this since I don't work with linux, but I tried almost everything on the internet.
Every of these commands are used in a .gitlab-ci.yml file, used for gitlab pipeline.
Here are some examples of what I've tried so far:
- sudo cp /builds/project/openjdk-17_linux-x64_bin.tar.gz /usr/lib/jvm
- sudo tar zxvf "/usr/lib/jvm/openjdk-17_linux-x64_bin.tar.gz" -C /usr/lib/jvm
- echo "JAVA_HOME=/usr/lib/jvm/jdk-17" | sudo tee -a /etc/profile
- echo "PATH=${PATH}:${HOME}/bin:${JAVA_HOME}/bin" | sudo tee -a /etc/profile
- echo "export JAVA_HOME" | sudo tee -a /etc/profile
- echo "export JRE_HOME" | sudo tee -a /etc/profile
- echo "export PATH" | sudo tee -a /etc/profile
- sudo cat /etc/profile
- echo "JAVA_HOME=/usr/lib/jvm/jdk-17" | sudo tee -a /.bashrc
- echo "PATH=${PATH}:${JAVA_HOME}/bin" | sudo tee -a /.bashrc
- echo "JAVA_HOME='/usr/lib/jvm/jdk-17' | sudo tee -a /etc/environment"
- export JAVA_HOME=/usr/lib/jvm/jdk-17
- export PATH=$PATH:$JAVA_HOME/bin
After a lot of combinations of these commands the output of sudo update-alternatives --config java is still:
openjdk version "11.0.12" 2021-07-20
OpenJDK Runtime Environment (build 11.0.12+7-post-Debian-2deb10u1)
OpenJDK 64-Bit Server VM (build 11.0.12+7-post-Debian-2deb10u1, mixed mode, sharing)
But if I try /usr/lib/jvm/jdk-17/bin/java -version it prints 17.
What would be the solution of making the default Java version to be 17. (Also a solution for ant to use the JDK-17 without installing it would be great too, since I need the JDK-17 for ant)

Since you've already found a way to change the jdk on-the-go, you may really want to consider change the base image of your CI to save yourself a lot of time. This step will boost your CI speed. The steps to do that is fairly simple too.
Compose your own Dockerfile
This following is just a pesudo code. You may look into the description of dockerfile builder
FROM your-original-image. This is what you have in your image tag in the gitlab-ci file.
COPY jdk-17-linux-x64.tar.gz /usr/lib/jvm
RUN sudo tar zxvf "/usr/lib/jvm/jdk-17-linux-x64.tar.gz" -C /usr/lib/jvm \
&& sudo \cp -r /usr/lib/jvm/jdk-17 /usr/lib/jvm/java-1.11.0-openjdk-amd64 \
&& sudo \cp -r /usr/lib/jvm/jdk-17 /usr/lib/jvm/default-java \
&& sudo \cp -r /usr/lib/jvm/jdk-17 /usr/lib/jvm/java-11-openjdk-amd64 \
&& sudo \cp -r /usr/lib/jvm/jdk-17 /usr/lib/jvm/openjdk-11 \
&& sudo update-alternatives --remove-all java \
&& sudo update-alternatives --remove-all javac \
&& sudo update-alternatives --install /usr/bin/java java /usr/lib/jvm/jdk-17/bin/java 1
Build the docker image
If you are using docker hub, then you need to login to docker and get a dockerId which matches the dockerId in the snippet.
If you are using a private repo like harbor or artifactory, you may need the permission to push to it.
docker build . -t dockerId/Name-of-your-image-you-want:latest
Upload the docker image using docker push
docker push dockerId/Name-of-your-image-you-want:latest
change the image tag in your gitlab-ci.yaml to dockerId/Name-of-your-image-you-want:latest

I found a solution.
- sudo cp jdk-17-linux-x64.tar.gz /usr/lib/jvm
- sudo tar zxvf "/usr/lib/jvm/jdk-17-linux-x64.tar.gz" -C /usr/lib/jvm
- sudo \cp -r /usr/lib/jvm/jdk-17 /usr/lib/jvm/java-1.11.0-openjdk-amd64
- sudo \cp -r /usr/lib/jvm/jdk-17 /usr/lib/jvm/default-java
- sudo \cp -r /usr/lib/jvm/jdk-17 /usr/lib/jvm/java-11-openjdk-amd64
- sudo \cp -r /usr/lib/jvm/jdk-17 /usr/lib/jvm/openjdk-11
- sudo update-alternatives --remove-all java
- sudo update-alternatives --remove-all javac
- sudo update-alternatives --install /usr/bin/java java /usr/lib/jvm/jdk-17/bin/java 1
What I did here was to copy the JDK-17 content to all folders from /usr/lib/jvm folder. So even though the docker image uses JDK-11, I'm rewriting it using JDK-17 uploaded with the source code, and now the tool is built using JKD-17.
PS: I know this is slower and not professional, but in my case, it's easier and more convinient than trying to get help from those who setup the docker container.

Logs stucks when deployment is done through teamcity

Recently we migrated to Teamcity deployment from manual process. Ours is java application on linux server.
Whenever deployment is done through Teamcity, logs are stuck i.e. after shutdown log messages nothing else is printed in the logs. Then we run manual stop and start scripts on the server to get the logs running.
Looks like somehow Teamcity locks log file and doesn't release it.
How to overcome it?
In Teamcity, deploy step is defined as below:
REMOTE_PATH="/opt/app/$ARTIFACT/releases/teamcity"
cd $TEAMCITY_REPO_HOME/$ARTIFACT/build/libs
echo "Uploading artifact"
ssh $UAT_HOST -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no "mkdir -p $REMOTE_PATH"
scp -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no $ARTIFACT.jar $UAT_HOST:$REMOTE_PATH
echo "Stopping service"
ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no $UAT_HOST "sh /opt/app/$ARTIFACT/stop.sh"
sleep 3s
echo "Copying new artifact"
ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no $UAT_HOST "cp $REMOTE_PATH/$ARTIFACT.jar /opt/app/$ARTIFACT"
sleep 6s
echo "Starting service"
ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no $UAT_HOST "sh /opt/app/$ARTIFACT/start.sh"

Taking ideas from above comments of Andy Dufresne, I created one deploy script as below:
This single script stops server, takes backup of current artifact, copies new build and then executes start script to start the server.
#!/bin/bash
#check for correct number of arguments
if [ "$#" -ne 1 ]; then
echo "Incorrect number of arguments, exiting..."
exit 1
fi
ARTIFACT=$1
cd "/opt/app/$ARTIFACT"
echo $(pwd)
echo "Stopping service"
bash stop.sh
sleep 3s
echo "Tagging artifact with release"
cp "releases/teamcity/$ARTIFACT.jar" "releases/teamcity/$ARTIFACT`date +'_%y_%m_%d'`.jar"
echo "Deleting old releases"
cd "releases/teamcity" && \
ls | grep -v '/$' | head -n -6 | xargs -d '\n' -r rm -- && \
cd "/opt/app/$ARTIFACT" && \
ls -l "releases/teamcity"
echo "Copying new artifact"
cp "releases/teamcity/$ARTIFACT.jar" .
echo "Starting service"
bash start.sh
sleep 2s
This script is called from team-city in its build steps(previously stopping server, copying artifact and starting server all were done by teamcity explicitly as outlined in the question.)
Now teamcity build step looks concise as under and WORKS as expected(that important !!!):
REMOTE_PATH="/opt/app/$ARTIFACT/releases/teamcity"
cd $TEAMCITY_REPO_HOME/$ARTIFACT/build/libs
echo "Uploading artifact"
ssh -o "StrictHostKeyChecking=no" "$UAT_HOST" "mkdir -p $REMOTE_PATH"
scp -o "StrictHostKeyChecking=no" "$ARTIFACT.jar" "$UAT_HOST:$REMOTE_PATH"
echo "Deploying artifact"
ssh -o "StrictHostKeyChecking=no" "$UAT_HOST" "sh /opt/app/$ARTIFACT/deploy.sh $ARTIFACT"

Cannot reinstall Cassandra on Ubuntu 18.04

I have a standard version of Ubuntu 18.04 freshly installed and want to use it as a Cassandra node.
I went through the following steps to install Cassandra:
##
## Install java 1.8
sudo apt install openjdk-8-jre -y
##
## Check java version
java -version
##
## Create the JAVA_HOME link
echo "JAVA_HOME=$(readlink -f /usr/bin/java | sed "s:bin/java::")" | sudo tee -a /etc/profile
source /etc/profile
echo $JAVA_HOME
##
## Create the Apache Cassandra 3.11.x apt repo:
echo "deb http://www.apache.org/dist/cassandra/debian 311x main" | sudo tee -a /etc/apt/sources.list.d/cassandra.sources.list
curl https://www.apache.org/dist/cassandra/KEYS | sudo apt-key add -
sudo apt-get update
##
## If GPG public key error
sudo apt-key adv --keyserver pool.sks-keyservers.net --recv-key A278B781FE4B2BDA
sudo apt-get update
##
## Install cassandra
sudo apt-get install cassandra
##
## Service status
sudo service cassandra status
Output:
cassandra.service - LSB: distributed storage system for structured data
Loaded: loaded (/etc/init.d/cassandra; generated)
Active: active (exited) since Thu 2018-08-02 23:03:47 UTC; 4h 2min ago
Docs: man:systemd-sysv-generator(8)
Tasks: 0 (limit: 4662)
CGroup: /system.slice/cassandra.service
The "active (exited)" part makes me think something went wrong.
I wanted to give it a re-try, and uninstall cassandra by doing:
sudo apt-get remove cassandra
sudo apt-get purge "cassandra-*"
sudo rm -rf /var/lib/cassandra
sudo rm -rf /var/log/cassandra
sudo rm -rf /etc/cassandra
sudo apt-get update
went through the same installing steps, and now /etc/cassandra contains only /triggers/, all configuration files are missing.
My guess is that I haven't completely cleant up something

In my limited debian/ubuntu experience, purging a package does nothing for removing dependencies. So people make the mistake that if they purge a package, then their system is returned to the state that it was in before the package was installed, which isn't true because all off the dependencies and their config files are still in the system.
So when removing a package, remove the dependencies too. I would do something like this:
sudo apt-get remove package_name
sudo apt-get purge package_name
sudo apt-get --purge autoremove
sudo apt-get clean
As far as your original problem, I would ask if it logged any errors in /var/log/cassandra/system.log but it looks like you deleted the logs.
Did java -version output what you expected?
Also make sure you have python and python-support installed
After doing a google search, you could check this out
Cassandra status changing from active(running) to active(exited) without any errors

How to run Docker with python and Java?

I need both java and python in my docker container to run some code.
This is my dockerfile:
It works perpectly if I don't add the FROM openjdk:slim
#get python
FROM python:3.6-slim
RUN pip install --trusted-host pypi.python.org flask
#get openjdk
FROM openjdk:slim
COPY . /targetdir
WORKDIR /targetdir
# Make port 81 available to the world outside this container
EXPOSE 81
CMD ["python", "test.py"]
And the test.py app is in the same directory:
from flask import Flask
import os
app = Flask(__name__)
#app.route("/")
def hello():
html = "<h3>Test:{test}</h3>"
test = os.environ['JAVA_HOME']
return html.format(test = test)
if __name__ == '__main__':
app.run(debug=True,host='0.0.0.0',port=81)
I'm getting this error:
D:\MyApps\Docker Toolbox\Docker Toolbox\docker.exe: Error response from daemon: OCI runtime create failed: container_linux.go:348: starting container process caused "exec: \"python\": executable file not found in $PATH": unknown.
What exactly am I doing wrong here? I'm new to docker, perhaps I'm missing a step.
Additional details
My goal
I have to run a python program that runs a Java file. The python library I'm using requires the path to JAVA_HOME.
My issues:
I do not know Java, so I cannot run the file properly.
My entire code is in Python, except this Java bit
The Python wrapper runs the file in a way I need it to run.

An easier solution to the above issue is to use multi-stage docker containers where you can copy the content from one to another. In the above case you can have openjdk:slim as the base container and then use content from a python container to be copied over into this base container as follows:
FROM openjdk:slim
COPY --from=python:3.6 / /
...
<normal instructions for python container continues>
...
This feature is available as of Docker 17.05 and there are more things you can do using multi-stage build as in copying only the content you need from one to another.
Reference documentation

OK it took me a little while to figure it out. And my thanks go to this answer.
I think my approach didn't work because I did not have a basic version of Linux.
So it goes like this:
Get Linux (I'm using Alpine because it's barebones)
Get Java via the package manager
Get Python, PIP
OPTIONAL: find and set JAVA_HOME
Find the path to JAVA_HOME. Perhaps there is a better way to do this, but I did this running the running the container, then I looked inside the container using docker exec -it [COINTAINER ID] bin/bash and found it.
Set JAVA_HOME in dockerfile and build + run it all again
Here is the final Dockerfile ( it should work with the python code in the question) :
### 1. Get Linux
FROM alpine:3.7
### 2. Get Java via the package manager
RUN apk update \
&& apk upgrade \
&& apk add --no-cache bash \
&& apk add --no-cache --virtual=build-dependencies unzip \
&& apk add --no-cache curl \
&& apk add --no-cache openjdk8-jre
### 3. Get Python, PIP
RUN apk add --no-cache python3 \
&& python3 -m ensurepip \
&& pip3 install --upgrade pip setuptools \
&& rm -r /usr/lib/python*/ensurepip && \
if [ ! -e /usr/bin/pip ]; then ln -s pip3 /usr/bin/pip ; fi && \
if [[ ! -e /usr/bin/python ]]; then ln -sf /usr/bin/python3 /usr/bin/python; fi && \
rm -r /root/.cache
### Get Flask for the app
RUN pip install --trusted-host pypi.python.org flask
####
#### OPTIONAL : 4. SET JAVA_HOME environment variable, uncomment the line below if you need it
#ENV JAVA_HOME="/usr/lib/jvm/java-1.8-openjdk"
####
EXPOSE 81
ADD test.py /
CMD ["python", "test.py"]
I'm new to Docker, so this may not be the best possible solution. I'm open to suggestions.
UPDATE: COMMON ISUUES
Difficulty using python packages
As Joabe Lucena pointed out here, Alpine can have issues certain python packages.
I recommend that you use a Linux distro that works best for you, e.g. centos.

Another alternative is to simply use docker-java-python image from docker hub. https://hub.docker.com/r/rappdw/docker-java-python
FROM rappdw/docker-java-python:openjdk1.8.0_171-python3.6.6
RUN java -version
RUN python --version

I found Sunny Pal's answer very useful but I made the copy more specific and added the necessary environment variables and update-alternatives lines so that Java was accessible from the command line in the Python container.
FROM python:3.9-slim
COPY --from=openjdk:8-jre-slim /usr/local/openjdk-8 /usr/local/openjdk-8
ENV JAVA_HOME /usr/local/openjdk-8
RUN update-alternatives --install /usr/bin/java java /usr/local/openjdk-8/bin/java 1
...

Oh, let me add my five cents. I took python slim as a base image. Then I found open-jdk-11 (Note, open-jdk-10 will fail because it is not supported) base image code!... And copy-pasted it into my docker file.
Note, copy-paste driven development is cool... ONLY when you understand each line you use in your code!!!
And here it is!
<!-- language: shell -->
FROM python:3.7.2-slim
# Do your stuff, install python.
# and now Jdk
RUN rm -rf /var/lib/apt/lists/* && apt-get clean && apt-get update && apt-get upgrade -y \
&& apt-get install -y --no-install-recommends curl ca-certificates \
&& rm -rf /var/lib/apt/lists/*
ENV JAVA_VERSION jdk-11.0.2+7
COPY slim-java* /usr/local/bin/
RUN set -eux; \
ARCH="$(dpkg --print-architecture)"; \
case "${ARCH}" in \
ppc64el|ppc64le) \
ESUM='c18364a778b1b990e8e62d094377af48b000f9f6a64ec21baff6a032af06386d'; \
BINARY_URL='https://github.com/AdoptOpenJDK/openjdk11-binaries/releases/download/jdk-11.0.1%2B13/OpenJDK11U-jdk_ppc64le_linux_hotspot_11.0.1_13.tar.gz'; \
;; \
s390x) \
ESUM='e39aacc270731dadcdc000aaaf709adae7a08113ccf5b4a045bc87fc13458d71'; \
BINARY_URL='https://github.com/AdoptOpenJDK/openjdk11-binaries/releases/download/jdk-11%2B28/OpenJDK11-jdk_s390x_linux_hotspot_11_28.tar.gz'; \
;; \
amd64|x86_64) \
ESUM='d89304a971e5186e80b6a48a9415e49583b7a5a9315ba5552d373be7782fc528'; \
BINARY_URL='https://github.com/AdoptOpenJDK/openjdk11-binaries/releases/download/jdk-11.0.2%2B7/OpenJDK11U-jdk_x64_linux_hotspot_11.0.2_7.tar.gz'; \
;; \
aarch64|arm64) \
ESUM='b66121b9a0c2e7176373e670a499b9d55344bcb326f67140ad6d0dc24d13d3e2'; \
BINARY_URL='https://github.com/AdoptOpenJDK/openjdk11-binaries/releases/download/jdk-11.0.1%2B13/OpenJDK11U-jdk_aarch64_linux_hotspot_11.0.1_13.tar.gz'; \
;; \
*) \
echo "Unsupported arch: ${ARCH}"; \
exit 1; \
;; \
esac; \
curl -Lso /tmp/openjdk.tar.gz ${BINARY_URL}; \
sha256sum /tmp/openjdk.tar.gz; \
mkdir -p /opt/java/openjdk; \
cd /opt/java/openjdk; \
echo "${ESUM} /tmp/openjdk.tar.gz" | sha256sum -c -; \
tar -xf /tmp/openjdk.tar.gz; \
jdir=$(dirname $(dirname $(find /opt/java/openjdk -name javac))); \
mv ${jdir}/* /opt/java/openjdk; \
export PATH="/opt/java/openjdk/bin:$PATH"; \
apt-get update; apt-get install -y --no-install-recommends binutils; \
/usr/local/bin/slim-java.sh /opt/java/openjdk; \
apt-get remove -y binutils; \
rm -rf /var/lib/apt/lists/*; \
rm -rf ${jdir} /tmp/openjdk.tar.gz;
ENV JAVA_HOME=/opt/java/openjdk \
PATH="/opt/java/openjdk/bin:$PATH"
ENV JAVA_TOOL_OPTIONS="-XX:+UseContainerSupport"
Now references.
https://github.com/AdoptOpenJDK/openjdk-docker/blob/master/11/jdk/ubuntu/Dockerfile.hotspot.releases.slim
https://hub.docker.com/_/python/
https://hub.docker.com/r/adoptopenjdk/openjdk11/
I used them to answer this question, which may help you sometime.
Running Python and Java in Docker

I believe that by adding FROM openjdk:slim line, you tell docker to execute all of your subsequent commands in openjdk container (which does not have python)
I would approach this by creating two separate containers for openjdk and python and specify individual sets of commands for them.
Docker is made to modularize your solutions and mashing everything into one container is usually a bad practice.

I tried pajamas's anwser which worked very well for creating this image. However, when trying to install packages like gensim, pandas or else, I faced some errors like: don't know how to compile Fortran code on platform 'posix'. I searched and tried this, this and that but none worked for me.
So, based on pajamas's anwser I decided to convert his image from Alpine to Centos which worked very well. So here's a Dockerfile that might help someone who's may be struggling in this scenario like I was:
# Get Linux
FROM centos:7
# Install Java
RUN yum update -y \
&& yum install java-1.8.0-openjdk -y \
&& yum clean all \
&& rm -rf /var/cache/yum
# Set JAVA_HOME environment var
ENV JAVA_HOME="/usr/lib/jvm/jre-openjdk"
# Install Python
RUN yum install python3 -y \
&& pip3 install --upgrade pip setuptools wheel \
&& if [ ! -e /usr/bin/pip ]; then ln -s pip3 /usr/bin/pip ; fi \
&& if [[ ! -e /usr/bin/python ]]; then ln -sf /usr/bin/python3 /usr/bin/python; fi \
&& yum clean all \
&& rm -rf /var/cache/yum
CMD ["bash"]

you should have one FROM in your dockerfile
(unless you use multi-stage build for the docker)

I think i found easiest way to mix java jdk 17 and python3. I is not working on python2
FROM openjdk:17.0.1-jdk-slim
RUN apt-get update && \
apt-get install -y software-properties-common && \
apt-get install -y python3-pip
Software Commons have python3 lightweight version. (3.9.1 version)
U can also install some libraries like that.
RUN python3 -m pip install --upgrade pip && \
python3 -m pip install numpy && \
python3 -m pip install opencv-python
OR
RUN apt-get update && \
apt-get install -y ffmpeg

Easiest is to just start from a Python image and add the OpenJDK. Note that FROM openjdk has been deprecated and replaced with eclipse-temurin
FROM python:3.10
ENV JAVA_HOME=/opt/java/openjdk
COPY --from=eclipse-temurin:17-jre $JAVA_HOME $JAVA_HOME
ENV PATH="${JAVA_HOME}/bin:${PATH}"
RUN pip install --trusted-host pypi.python.org flask
See How to use this Image - Using a different base Image section of https://hub.docker.com/_/eclipse-temurin for details.

Instead of using FROM openjdk:slim you can separately install Java, please refer below example:
# Install OpenJDK-8
RUN apt-get update && \
apt-get install -y openjdk-8-jdk && \
apt-get install -y ant && \
apt-get clean;
# Fix certificate issues
RUN apt-get update && \
apt-get install ca-certificates-java && \
apt-get clean && \
update-ca-certificates -f;
# Setup JAVA_HOME -- useful for docker commandline
ENV JAVA_HOME /usr/lib/jvm/java-8-openjdk-amd64/
RUN export JAVA_HOME