首页 > 解决方案 > 通过k8s作业文件将cmd参数传递给docker容器中的java应用程序

问题描述

我试图了解如何将命令行参数传递给我的 java 应用程序,该应用程序被容器化在我想从 Kubernetes 运行的 Docker 容器中。让我告诉你我到目前为止做了什么。码头工人文件:

FROM java:8
WORKDIR /
ADD myApp.jar myApp.jar
COPY entry-point.sh /
RUN chmod +x entry-point.sh
EXPOSE 8080
ENTRYPOINT ["/entry-point.sh"]

有这样的entry-point.sh内容:

#!/bin/sh
echo "arguments: $1"
java -jar myApp.jar $1

k8s 文件:

    apiVersion: batch/v1
    metadata:
      name: myapp-test-job
      namespace: myNamespace
    kind: Job
    metadata:
      name: myapp
    spec:
      template:
        metadata:
          labels:
            app: myapp
        spec:
          containers:
          - args:
            - -c
            - /opt/config/configuration.yml
            name: myapp
            image: myapp:latest
            imagePullPolicy: Never
            args:
            volumeMounts:
              - name: config
                mountPath: /opt/config
          restartPolicy: Never
          volumes:
            - name: config
              configMap:
                name: configurations
                items:
                - key: "configuration.yml"
                  path: "configuration.yml"
---
apiVersion: v1
kind: ConfigMap
metadata:
  name: configurations
  namespace: myapp
data:
  configuration.yml: |
    #HERE ALL THE CONFIGS

应用程序本身已执行,但找不到配置文件,我看到了entry-point.sh文件的输出:arguments:,但我猜我在 kubernetes 文件中声明的参数根本没有传递给入口点文件,我认为这是: ENTRYPOINT ["/entry-point.sh"]当需要传递参数时,格式不正确。有人有建议吗?

标签: javadockerkubernetes

解决方案


您的脚本仅使用第一个参数$1。有一个特殊变量$@可以扩展到所有参数,因此您可以将脚本更改为:

#!/bin/sh
echo "arguments: $@"
# $@ and not $1; make sure to quote it as well
java -jar myApp.jar "$@"

如果您的包装脚本只是将其选项传递给一些底层程序,那么放弃包装脚本并让程序成为 Docker 可能是有意义的ENTRYPOINT。(或者,如果您需要在启动命令之前进行一些初始设置,请保留包装器。)

# The main command to run.  Should be enough to actually run the
# application (don't use just ["java"]).  Must be JSON-array syntax.
ENTRYPOINT ["java", "-jar", "myApp.jar"]

# Additional options to the program.  Can be overridden with options
# after the `docker run image-name`, Compose `command:`, or
# Kubernetes `args:`.  Must be JSON-array syntax.
CMD []
# (including the previous line is optional)

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