CentOS 安装 PlantUML

PlantUML 本身就是一个jar文件，完全可以下载该文件后放入环境变量
但是还需要安装 Java、GraphViz 等依赖环境，因此使用自动安装脚本更方便一点

# Install PlantUML
PLANTUML_URL="${PLANTUML_URL:-http://sourceforge.net/projects/plantuml/files/plantuml.jar/download}"

if [ -f "/opt/plantuml/plantuml.jar" ]; then
  echo '[plantuml] PlantUML already installed.'
else
  echo '[plantuml] Installing PlantUML...'
  yum install -y java-1.8.0-openjdk graphviz
  mkdir -p /opt/plantuml && \
    curl -o /opt/plantuml/plantuml.jar \
    -L ${PLANTUML_URL}
  printf '#!/bin/sh\nexec java -jar /opt/plantuml/plantuml.jar "$@"' > /usr/bin/plantuml
  chmod +x /usr/bin/plantuml
fi