- 需求 : php7.1 + nginx
- php扩展: yaf、redis、ldap、pdo、mbstring、 mcrypt
阅读完本文后,你能解决以下常见问题:
- 如何写Dockerfile,并通过Dockerfile构建镜像。
- 如何通过supervisord管理进程,并将进程日志通过docker logs {container}输出
实现步骤
我们的镜像基于centos:7系统, Dockerfile代码如下:
FROM centos:7
MAINTAINER [email protected]
RUN rpm -Uvh http://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm
&& rpm -Uvh https://sp.repo.webtatic.com/yum/el7/webtatic-release.rpm
&& yum update -y
&& yum install -y wget
sed
gcc
gcc-c++
gd
gd-devel
gmp-devel
epel-release
net-tools
ntpdate
ntp
openssh-clients
curl
crontabs
openssl
openssl-devel
nginx
squid
php71w
php71w-fpm
php71w-gd
php71w-soap
php71w-pdo_mysql
php71w-pear
php71w-devel
php71w-mbstring
php71w-mcrypt
php71w-ldap
&& yum update -y ntp ntpdate kernel-headers
&& yum clean all
&& sed -i 's/http_access deny all/#http_access deny all/g' /etc/squid/squid.conf
&& cd /tmp
&& wget -O get-pip.py https://bootstrap.pypa.io/get-pip.py
&& python get-pip.py
&& pip install supervisor
&& mkdir -p /etc/supervisor.d/*.conf
&& pecl install mongodb
&& pecl install yaf
&& wget -c https://github.com/phpredis/phpredis/archive/3.1.4.tar.gz
&& tar zxvf 3.1.4.tar.gz
&& cd phpredis-3.1.4
&& phpize
&& ./configure
&& make
&& make install
&& cd ..
&& rm -rf phpredis*
&& rm 3.1.4.tar.gz
&& echo "" >> /etc/php.ini
&& echo "extension=redis.so" >> /etc/php.ini
&& echo "extension=yaf.so" >> /etc/php.ini
&& echo "extension=mongodb.so" >> /etc/php.ini
&& echo "[yaf]" >> /etc/php.ini
&& echo "yaf.use_namespace = 1" >> /etc/php.ini
COPY ./supervisord.conf /etc/
COPY ./default.conf /etc/nginx/conf.d/
COPY ./nginx.conf /etc/supervisor.d/
COPY ./php.conf /etc/supervisor.d/
COPY ./ntpdate.conf /etc/supervisor.d/
COPY ./nginx.conf.def /etc/nginx/nginx.conf
COPY ./index.php /data/work/code/
EXPOSE 80 443 3128
WORKDIR /data/work/code
CMD ["supervisord","-c","/etc/supervisord.conf"]
问题
子进程stdout如何重定向到supervisord
Supervisor的监督进程supervisord可以捕获所管理子进程的stdout及stderr,并可以配置为写入日志文件
镜像初步构建成功时,运行容器,并通过 docker logs -f {container} 查看容器日志,总是提示错误, 如下:
2017-11-09 07:41:41,256 CRIT uncaptured python exception, closing channel <POutputDispatcher at 36463248 for <Subprocess at 35644984 with name nginx in state RUNNING> (stderr)> (<type 'exceptions.IOError'>:[Errno 29] Illegal seek [/usr/lib/python2.7/site-packages/supervisor/supervisord.py|runforever|227] [/usr/lib/python2.7/site-packages/supervisor/dispatchers.py|handle_read_event|232] [/usr/lib/python2.7/site-packages/supervisor/dispatchers.py|record_output|166] [/usr/lib/python2.7/site-packages/supervisor/dispatchers.py|_log|142] [/usr/lib/python2.7/site-packages/supervisor/loggers.py|info|275] [/usr/lib/python2.7/site-packages/supervisor/loggers.py|log|293] [/usr/lib/python2.7/site-packages/supervisor/loggers.py|emit|186] [/usr/lib/python2.7/site-packages/supervisor/loggers.py|doRollover|211])
经过了N多次查询,N多次尝试,终于找到原因,原来是在配置supervisord管理的子进程文件时,如果配置了stdout_logfile=/dev/stdout, 则必须一块配置stdout_logfile_maxbytes=0
查找的资料说明如下:
If anyone stumbles upon this error like me, be aware that the mentioned options apply to the [supervisord] section, within [program:x] sections, you need to use stdout_logfile_maxbytes = 0and/or stderr_logfile_maxbytes = 0 respectively.
using stdout_logfile=/dev/stdout along with stdout_logfile_maxbytes=0
对于需要将supervisord管理的子进程的日志输出到stdout的program, 配置如下:
[program:php7-fpm]
command=/usr/local/sbin/php-fpm
autostart = true
stderr_logfile = /dev/stdout
stdout_logfile = /dev/stdout
stdout_logfile_maxbytes = 0
stderr_logfile_maxbytes = 0
参见: http://veithen.github.io/2015/01/08/supervisord-redirecting-stdout.html
php-fpm 的错误日志如何定向到docker logs
看到 https://github.com/docker-library/php/issues/63 解释,将error_log及access.log的配置改成如下error_log=/proc/self/fd/2 和 access.log=/proc/self/fd2即可,一直不明白,/proc/self/fd/2和/dev/stdout /dev/stderr有什么联系,经过ls -al /dev 才明白:
lrwxrwxrwx 1 root root 15 Nov 9 07:44 stderr -> /proc/self/fd/2
lrwxrwxrwx 1 root root 15 Nov 9 07:44 stdin -> /proc/self/fd/0
lrwxrwxrwx 1 root root 15 Nov 9 07:44 stdout -> /proc/self/fd/1
对于我们的需求,是将错误及access信息都在docker logs 中显示,所以,我们配置php-fpm.conf如下:
[global]
error_log=/proc/self/fd/1
文件/etc/php-fpm.d/www.conf配置如下:
php_admin_value[error_log] = /proc/self/fd/1
slowlog = /proc/self/fd/1
catch_workers_output = yes
clear_env=no