不能回显码头容器中的env var

Question

我构建了一个包含许多环境变量的坞映像，其中包括一个名为SPARK_HOME的环境变量。下面是声明env的Dockerfile中的一行：

ENV SPARK_HOME="/opt/spark"

当我发出docker run时，我可以看到env存在，但是对它的任何引用都不会返回任何内容，如简单的echo所示

$ docker run --rm myimage /bin/bash -c "env | grep SPARK_HOME ; echo SPARK_HOME=$SPARK_HOME"
SPARK_HOME=/opt/spark
SPARK_HOME=
$

我是不是漏掉了什么明显的东西？为什么不能引用现有env的值？

编辑1:根据注释中的要求，Dockerfile内容包含在下面的中断下面。

编辑2:发现如果我以交互方式运行容器，就可以引用var

$ docker run --rm -it myimage /bin/bash 
root@419dd5f13a6f:/tmp# echo $SPARK_HOME
/opt/spark

FROM our.internal.artifact.store/python:3.7-stretch

WORKDIR /tmp

ENV SPARK_VERSION=2.2.1
ENV HADOOP_VERSION=2.8.4

ARG ARTIFACTORY_USER
ARG ARTIFACTORY_ENCRYPTED_PASSWORD
ARG ARTIFACTORY_PATH=our.internal.artifact.store/artifactory/generic-dev/ceng/external-dependencies
ARG SPARK_BINARY_PATH=https://${ARTIFACTORY_PATH}/spark-${SPARK_VERSION}-bin-hadoop2.7.tgz
ARG HADOOP_BINARY_PATH=https://${ARTIFACTORY_PATH}/hadoop-${HADOOP_VERSION}.tar.gz


ADD files/apt-transport-https_1.4.8_amd64.deb /tmp

RUN echo "deb https://username:password@our.internal.artifact.store/artifactory/debian-main-remote stretch main" >/etc/apt/sources.list.d/main.list &&\
    echo "deb https://username:password@our.internal.artifact.store/artifactory/maria-db-debian stretch main" >>/etc/apt/sources.list.d/main.list &&\
    echo 'Acquire::CompressionTypes::Order:: "gz";' > /etc/apt/apt.conf.d/02update &&\
    echo 'Acquire::http::Timeout "10";' > /etc/apt/apt.conf.d/99timeout &&\
    echo 'Acquire::ftp::Timeout "10";' >> /etc/apt/apt.conf.d/99timeout &&\
    dpkg -i /tmp/apt-transport-https_1.4.8_amd64.deb &&\
    apt-get install --allow-unauthenticated -y /tmp/apt-transport-https_1.4.8_amd64.deb &&\
    apt-get update --allow-unauthenticated -y -o Dir::Etc::sourcelist="sources.list.d/main.list" -o Dir::Etc::sourceparts="-" -o APT::Get::List-Cleanup="0"


RUN apt-get update && \
    apt-get -y install default-jdk

# Detect JAVA_HOME and export in bashrc.
# This will result in something like this being added to /etc/bash.bashrc
#   export JAVA_HOME=/usr/lib/jvm/java-8-openjdk-amd64
RUN echo export JAVA_HOME="$(readlink -f /usr/bin/java | sed "s:/jre/bin/java::")" >> /etc/bash.bashrc

# Configure Spark-${SPARK_VERSION}
RUN curl --fail -u "${ARTIFACTORY_USER}:${ARTIFACTORY_ENCRYPTED_PASSWORD}" -X GET "${SPARK_BINARY_PATH}" -o /opt/spark-${SPARK_VERSION}-bin-hadoop2.7.tgz \
    && cd /opt \
    && tar -xvzf /opt/spark-${SPARK_VERSION}-bin-hadoop2.7.tgz \
    && rm spark-${SPARK_VERSION}-bin-hadoop2.7.tgz \
    && ln -s spark-${SPARK_VERSION}-bin-hadoop2.7 spark \
    && sed -i '/log4j.rootCategory=INFO, console/c\log4j.rootCategory=CRITICAL, console' /opt/spark/conf/log4j.properties.template \
    && mv /opt/spark/conf/log4j.properties.template /opt/spark/conf/log4j.properties \
    && mkdir /opt/spark-optional-jars/ \
    && mv /opt/spark/conf/spark-defaults.conf.template /opt/spark/conf/spark-defaults.conf \
    && printf "spark.driver.extraClassPath /opt/spark-optional-jars/*\nspark.executor.extraClassPath /opt/spark-optional-jars/*\n">>/opt/spark/conf/spark-defaults.conf \
    && printf "spark.driver.extraJavaOptions -Dderby.system.home=/tmp/derby" >> /opt/spark/conf/spark-defaults.conf

# Configure Hadoop-${HADOOP_VERSION}
RUN curl --fail -u "${ARTIFACTORY_USER}:${ARTIFACTORY_ENCRYPTED_PASSWORD}" -X GET "${HADOOP_BINARY_PATH}" -o /opt/hadoop-${HADOOP_VERSION}.tar.gz \
    && tar -xvzf /opt/hadoop-${HADOOP_VERSION}.tar.gz \
    && rm /opt/hadoop-${HADOOP_VERSION}.tar.gz \
    && ln -s hadoop-${HADOOP_VERSION} hadoop

# Set Environment Variables.
ENV SPARK_HOME="/opt/spark" \
    HADOOP_HOME="/opt/hadoop" \
    PYSPARK_SUBMIT_ARGS="--master=local[*] pyspark-shell --executor-memory 1g --driver-memory 1g --conf spark.ui.enabled=false spark.executor.extrajavaoptions=-Xmx=1024m" \
    PYTHONPATH="/opt/spark/python:/opt/spark/python/lib/py4j-0.10.7-src.zip:$PYTHONPATH" \
    PATH="$PATH:/opt/spark/bin:/opt/hadoop/bin" \
    PYSPARK_DRIVER_PYTHON="/usr/local/bin/python" \
    PYSPARK_PYTHON="/usr/local/bin/python"

# Upgrade pip and setuptools
RUN pip install --index-url https://username:password@our.internal.artifact.store/artifactory/api/pypi/pypi-virtual-all/simple --upgrade pip setuptools

# Install core python packages
RUN pip install --index-url https://username:password@our.internal.artifact.store/artifactory/api/pypi/pypi-virtual-all/simple pipenv

ADD Pipfile /tmp

ADD pysparkdf_helloworld.py /tmp

Answer 1

好吧，与我的评论相反，这一点都不奇怪。

问题是您的本地shell在将它发送到容器之前已经插入了$SPARK_HOME，所以您基本上是在调用echo SPARK_HOME=

要修复，只需在命令中转义env var：$SPARK_HOME->\$SPARK_HOME

演示：

$ export SPARK_HOME=foo
$ docker run ... /bin/bash -c "env | grep SPARK_HOME ; echo SPARK_HOME=$SPARK_HOME"                                                            
> SPARK_HOME=/opt/spark
> SPARK_HOME=foo