jenkins使用docker-maven-plugin进行编译时发现没有权限，具体错误内容如下：INFO: I/O exception (java.io.IOException) caught when processing request to {}->unix://localhost:80: Permission denied Jun 19, 2017 4:48:41 PM org.apache.http.impl.execchain.RetryExec execute INFO: Retrying request to {}->unix://localhost:80
给jenkins用户组一个运行docker的权限即可，具体解决方法如下：
Try adding DOCKER_OPTS=' -G jenkins' directly in /etc/default/docker. Then restart docker service by sudo service docker restart
