openshift 中部署springboot項目並增量更新

最新公司準備應用openshift，於是安排我學習openshift，通過好幾天的學習，嘗試，踩過無數個坑，終於搭建起了一個Mater，一個Node的openshift環境：

公司後端項目是基於springboot，openshift沒有提供現有的is，所以需要通過s2i自己製作is，現記錄過程如下：

1. 下載s2i，過程略過...

2. 通過s2i創建鏡像：

s2i create springboot-s2i springboot-s2i

s2i目錄下爲S2I腳本。

其中：

assemble:負責源代碼的編譯、構建以及構建產出物的部署。
run:S2I流程生成的最終鏡像將以這個腳本作爲容器的啓動命令。
usage:打印幫助信息，一般作爲S2I Builder鏡像的啓動命令。
save-artifacts:爲了實現增量構建。稍後對針對springboot的增量更新做詳細說明

3. 編輯Dockfile文件：

#springboot-s2i
FROM maven:3.6-jdk-8

# TODO: Put the maintainer name in the image metadata
LABEL maintainer="huabing.li"

# TODO: Rename the builder environment variable to inform users about application you provide them
ENV MAVEN_CONFIG=.m2

# TODO: Set labels used in OpenShift to describe the builder image
LABEL io.openshift.s2i.scripts-url="image:///usr/libexec/s2i" \
      io.openshift.s2i.destination="/opt/s2i/destination"
#LABEL io.k8s.description="Platform for building xyz" \
#      io.k8s.display-name="builder x.y.z" \
#      io.openshift.expose-services="8080:http" \
#      io.openshift.tags="builder,x.y.z,etc."

# TODO: Install required packages here:
WORKDIR /opt

RUN useradd -m deploy -u 1001 && \
    chmod -R 777 /opt && \
    mkdir -p /opt/s2i/destination && \
    chmod -R 777 /opt/s2i/destination

# TODO: Copy the S2I scripts to /usr/libexec/s2i, since openshift/base-centos7 image
# sets io.openshift.s2i.scripts-url label that way, or update that label
COPY ./s2i/bin/ /usr/libexec/s2i

# TODO: Drop the root user and make the content of /opt/app-root owned by user 1001
RUN chown -R 1001:1001 /opt && \
    chown -R 1001:1001 /var

# This default user is created in the openshift/base-centos7 image
USER 1001

# TODO: Set the default port for applications built using this image
# EXPOSE 8080

# TODO: Set the default CMD for the image
# CMD ["/usr/libexec/s2i/usage"]

4. 編輯s2i/bin/assemble文件：

#!/bin/bash -e
#
# S2I assemble script for the 'springboot-s2i' image.
# The 'assemble' script builds your application source so that it is ready to run.
#
# For more information refer to the documentation:
#       https://github.com/openshift/source-to-image/blob/master/docs/builder_image.md
#

# If the 'springboot-s2i' assemble script is executed with the '-h' flag, print the usage.
if [[ "$1" == "-h" ]]; then
        exec /usr/libexec/s2i/usage
fi

# Restore artifacts from the previous build (if they exist).
#
if [ "$(ls -A /opt/s2i/destination/artifacts/ 2>/dev/null)" ]; then
  echo "---> Restoring build artifacts..."
  # ls -la /opt/s2i/destination/artifacts/home/deploy/.m2
  mv /opt/s2i/destination/artifacts/home/deploy/.m2 $HOME/.m2
fi

echo "---> Installing application source..."

cp -Rf /opt/s2i/destination/src/. ./

mvn compile -Dmaven.test.skip=true package

find . -type f -name '*.tar.gz'|xargs -i tar zxvf {}

echo "---> Building application from source..."
# TODO: Add build steps for your application, eg npm install, bundle install, pip install, etc.

5. 編輯s2i/bin/run文件

#!/bin/bash -e
#
# S2I run script for the 'springboot-s2i' image.
# The run script executes the server that runs your application.
#
# For more information see the documentation:
#       https://github.com/openshift/source-to-image/blob/master/docs/builder_image.md
#
# bash -c "java -jar financial-assistant.jar"

bash -c "bin/single.sh start ${SPRING_PROFILES_ACTIVE}"
tail -f logs/stdout.log

bin/single.sh腳本爲項目定製啓動腳本，此處可以換成具體的啓動命令；${SPRING_PROFILES_ACTIVE}是環境變量，表示項目啓動時應用那個profile。

6. 編輯增量文件

#!/bin/sh -e

tar cf - $HOME/.m2

7.編譯，並把創建的鏡像推到私有倉庫

1. make
2. docker tag springboot-s2i master.openshift.com:5000/springboot-s2i
3. docker push master.openshift.com:5000/springboot-s2i
4. oc import-image master.openshift.com:5000/springboot-s2i -n openshift --confirm --insecure

執行第4步需要登陸openshift並擁有管理員權限。

8. 編輯is，使得openshift能夠識別剛導入的is