从零开始nodejs系列文章,将介绍如何利Javascript作为服务端脚本,经过Nodejs框架web开发。Nodejs框架是基于V8的引擎,是目前速度最快的Javascript引擎。chrome浏览器就基于V8,同时打开20-30个网页都很流畅。Nodejs标准的web开发框架Express,能够帮助咱们迅速创建web站点,比起PHP的开发效率更高,并且学习曲线更低。很是适合小型网站,个性化网站,咱们本身的Geek网站!!javascript
关于做者html
转载请注明出处:
http://blog.fens.me/nodejs-server-forever/java
目前node
又说到服务器管理了,上次说的时候用的是Linux系统服务upstart, 今天准备尝试一下Nodejs本身模块化解决方案forever。linux
服务器管理是系统上线后,必需要面对的问题。最好有一个软件能够提供整套的服务器运行解决方案:要求运行稳定,支持高并发,启动/中止命令简单,支持热部署,宕机重启,监控界面和日志,集群环境。程序员
接下来,就让咱们看看forever能不能实现目标。web
前言chrome
forever是一个简单的命令式nodejs的守护进程,可以启动,中止,重启App应用。forever彻底基于命令行操做,在forever进程之下,建立node的子进程,经过monitor监控node子进程的运行状况,一旦文件更新,或者进程挂掉,forever会自动重启node服务器,确保应用正常运行。express
全局安装forevernpm
~ D:\workspace\javascript>npm install -g forever D:\toolkit\nodejs\forever -> D:\toolkit\nodejs\node_modules\forever\bin\forever D:\toolkit\nodejs\foreverd -> D:\toolkit\nodejs\node_modules\forever\bin\foreverd
查看forever帮助
~ D:\workspace\javascript>forever -h help: usage: forever [action] [options] SCRIPT [script-options] help: help: Monitors the script specified in the current process or as a daemon help: help: actions: help: start Start SCRIPT as a daemon help: stop Stop the daemon SCRIPT help: stopall Stop all running forever scripts help: restart Restart the daemon SCRIPT help: restartall Restart all running forever scripts help: list List all running forever scripts help: config Lists all forever user configuration help: set <key> <val> Sets the specified forever config <key> help: clear <key> Clears the specified forever config <key> help: logs Lists log files for all forever processes help: logs <script|index> Tails the logs for <script|index> help: columns add <col> Adds the specified column to the output in `forever list` help: columns rm <col> Removed the specified column from the output in `forever list` help: columns set <cols> Set all columns for the output in `forever list` help: cleanlogs [CAREFUL] Deletes all historical forever log files help: help: options: help: -m MAX Only run the specified script MAX times help: -l LOGFILE Logs the forever output to LOGFILE help: -o OUTFILE Logs stdout from child script to OUTFILE help: -e ERRFILE Logs stderr from child script to ERRFILE help: -p PATH Base path for all forever related files (pid files, etc.) help: -c COMMAND COMMAND to execute (defaults to node) help: -a, --append Append logs help: -f, --fifo Stream logs to stdout help: -n, --number Number of log lines to print help: --pidFile The pid file help: --sourceDir The source directory for which SCRIPT is relative to help: --minUptime Minimum uptime (millis) for a script to not be considered "spinning" help: --spinSleepTime Time to wait (millis) between launches of a spinning script. help: --colors --no-colors will disable output coloring help: --plain alias of --no-colors help: -d, --debug Forces forever to log debug output help: -v, --verbose Turns on the verbose messages from Forever help: -s, --silent Run the child script silencing stdout and stderr help: -w, --watch Watch for file changes help: --watchDirectory Top-level directory to watch from help: --watchIgnore To ignore pattern when watch is enabled (multiple option is allowed) help: -h, --help You're staring at it help: help: [Long Running Process] help: The forever process will continue to run outputting log messages to the console. help: ex. forever -o out.log -e err.log my-script.js help: help: [Daemon] help: The forever process will run as a daemon which will make the target process start help: in the background. This is extremely useful for remote starting simple node.js scripts help: without using nohup. It is recommended to run start with -o -l, & -e. help: ex. forever start -l forever.log -o out.log -e err.log my-daemon.js help: forever stop my-daemon.js help:
经过“Commander写本身的Nodejs命令”一文的介绍,咱们已经知道如何看懂,并实现自定义的命令行了。虽然,forever不是基于Commander的,而是基于另外一个命令行开发包optimist,原理都是相似的。
因此,咱们看到forever支持的命令和配置项确实很多,应该是偏命令行的管理工具。
子命令actions:
配置参数options:
建立一个web项目(express3+ejs),使用forever管理服务器。
安装express3
~ D:\workspace\javascript>express -e nodejs-forever ~ D:\workspace\javascript>cd nodejs-forever && npm install
经过forever启动应用
~ D:\workspace\javascript\nodejs-forever>forever start app.js warn: --minUptime not set. Defaulting to: 1000ms warn: --spinSleepTime not set. Your script will exit if it does not stay up for at least 1000ms info: Forever processing file: app.js
打开浏览器: http://localhost:3000,能够看到web界面
在win下面查看forever状态
~ D:\workspace\javascript\nodejs-forever>forever list info: No forever processes running ~ D:\workspace\javascript\nodejs-forever>forever stop app.js error: Forever cannot find process with index: app.js
咱们发现forever的程序,工做不对了!!程序明明是运行状态,经过list确看不到。接下来,切换成Linux Ubuntu继续测试。
Linux的系统环境
初始化项目:安装命令不解释了
~ cd /home/conan/nodejs ~ express -e nodejs-forever ~ cd nodejs-forever && npm install ~ sudo npm install forever -g
启动forever
~ forever start app.js warn: --minUptime not set. Defaulting to: 1000ms warn: --spinSleepTime not set. Your script will exit if it does not stay up for at least 1000ms info: Forever processing file: app.js
查看node服务器状态
~ forever list info: Forever processes running data: uid command script forever pid logfile uptime data: [0] L2tY /usr/local/bin/node app.js 18276 18279 /home/conan/.forever/L2tY.log 0:0:0:37.792 # 系统进程 ~ ps -aux|grep node Warning: bad ps syntax, perhaps a bogus '-'? See http://procps.sf.net/faq.html conan 18296 0.5 1.1 597696 23776 ? Ssl 15:48 0:00 /usr/local/bin/node /usr/local/lib/node_modules/forever/bin/monitor app.js conan 18299 0.4 0.8 630340 18392 ? Sl 15:48 0:00 /usr/local/bin/node /home/conan/nodejs/nodejs-forever/app.js # 端口占用 ~ netstat -nltp|grep node tcp 0 0 0.0.0.0:3000 0.0.0.0:* LISTEN 18299/node
中止服务器
~ forever stop app.js info: Forever stopped process: data: uid command script forever pid logfile uptime [0] L2tY /usr/local/bin/node app.js 18276 18279 /home/conan/.forever/L2tY.log 0:0:0:45.621
咱们看到在Linux Ubuntu环境中是正常的。
两种测试方案:
1). 用Linux命令,直接杀死node进程
# 查看node进程,PID=18299 ~ ps -aux|grep node conan 18296 0.0 1.1 597696 23776 ? Ssl 15:48 0:00 /usr/local/bin/node /usr/local/lib/node_modules/forever/bin/monitor app.js conan 18299 0.0 0.8 630340 18392 ? Sl 15:48 0:00 /usr/local/bin/node /home/conan/nodejs/nodejs-forever/app.js conan 18315 0.0 0.0 13584 956 pts/5 R+ 15:52 0:00 grep --color=auto node # 杀死PID=19299 ~ kill -9 18299 # 再看node进程,node自动重启,新的PID=18324 ~ ps -aux|grep node conan 18296 0.0 1.1 597696 23916 ? Ssl 15:48 0:00 /usr/local/bin/node /usr/local/lib/node_modules/forever/bin/monitor app.js conan 18316 2.6 0.8 630340 18412 ? Sl 15:52 0:00 /usr/local/bin/node /home/conan/nodejs/nodejs-forever/app.js conan 18324 0.0 0.0 13584 956 pts/5 R+ 15:52 0:00 grep --color=auto node
咱们看到看杀死node进程,forever会帮助咱们,重启node。
杀死forever的monitor
~ kill -9 18296 ~ ps -aux|grep node conan 18316 0.0 0.9 630340 18644 ? Sl 15:52 0:00 /usr/local/bin/node /home/conan/nodejs/nodejs-forever/app.js conan 18333 0.0 0.0 13584 952 pts/5 S+ 15:57 0:00 grep --color=auto node # 再杀死node进程 ~ kill -9 18316 ~ ps -aux|grep node conan 18336 0.0 0.0 13584 956 pts/5 S+ 15:58 0:00 grep --color=auto node
咱们尝试杀死了forever的monitor,monitor程序没有自动重启,而后再杀死node进程后,node也不会自动重启了。
2). 在应用中,模拟异常退出
修改文件:app.js
~ vi app.js //.. http.createServer(app).listen(app.get('port'), function(){ console.log(new Date()); console.log('Express server listening on port ' + app.get('port')); }); setTimeout(function(){ console.log(new Date()); throw new Error('App is error from inner!'); },10*1000);
经过node命令启动
~ node app.js Thu Sep 26 2013 16:08:44 GMT+0800 (CST) Express server listening on port 3000 Thu Sep 26 2013 16:08:54 GMT+0800 (CST) /home/conan/nodejs/nodejs-forever/app.js:41 throw new Error('App is error from inner!'); ^ Error: App is error from inner! at null._onTimeout (/home/conan/nodejs/nodejs-forever/app.js:41:9) at Timer.listOnTimeout [as ontimeout] (timers.js:110:15)
10秒后,因为内部错误, node进程挂掉了。
经过forever命令启动
~ mkdir logs ~ chmod 777 -R logs ~ forever -p . -l ./logs/access.log -e ./logs/error.log start app.js # 检查错误日志 ~ cat logs/access.log ls Thu Sep 26 2013 16:15:02 GMT+0800 (CST) Express server listening on port 3000 Thu Sep 26 2013 16:15:12 GMT+0800 (CST) /home/conan/nodejs/nodejs-forever/app.js:41 throw new Error('App is error from inner!'); ^ Error: App is error from inner! at null._onTimeout (/home/conan/nodejs/nodejs-forever/app.js:41:9) at Timer.listOnTimeout [as ontimeout] (timers.js:110:15) error: Forever detected script exited with code: 8 error: Forever restarting script for 1 time Thu Sep 26 2013 16:15:13 GMT+0800 (CST) Express server listening on port 3000 Thu Sep 26 2013 16:15:23 GMT+0800 (CST) /home/conan/nodejs/nodejs-forever/app.js:41 throw new Error('App is error from inner!'); ^ Error: App is error from inner! at null._onTimeout (/home/conan/nodejs/nodejs-forever/app.js:41:9) at Timer.listOnTimeout [as ontimeout] (timers.js:110:15) error: Forever detected script exited with code: 8 error: Forever restarting script for 2 time Thu Sep 26 2013 16:15:23 GMT+0800 (CST) Express server listening on port 3000 Thu Sep 26 2013 16:15:33 GMT+0800 (CST) /home/conan/nodejs/nodejs-forever/app.js:41 throw new Error('App is error from inner!'); ^ Error: App is error from inner! at null._onTimeout (/home/conan/nodejs/nodejs-forever/app.js:41:9) at Timer.listOnTimeout [as ontimeout] (timers.js:110:15) error: Forever detected script exited with code: 8 error: Forever restarting script for 3 time Thu Sep 26 2013 16:15:33 GMT+0800 (CST) Express server listening on port 3000 Thu Sep 26 2013 16:15:43 GMT+0800 (CST) /home/conan/nodejs/nodejs-forever/app.js:41 throw new Error('App is error from inner!'); ^ Error: App is error from inner! at null._onTimeout (/home/conan/nodejs/nodejs-forever/app.js:41:9) at Timer.listOnTimeout [as ontimeout] (timers.js:110:15) error: Forever detected script exited with code: 8 error: Forever restarting script for 4 time
咱们发现每10秒种,node内部挂掉,而后再被forever重启!!
经过list咱们手动刷新几回也能够看到pid是变的。
~ forever list info: Forever processes running data: uid command script forever pid logfile uptime data: [0] SmtT /usr/local/bin/node app.js 18444 18579 logs/access.log 0:0:0:7.211 ~ forever list info: Forever processes running data: uid command script forever pid logfile uptime data: [0] SmtT /usr/local/bin/node app.js 18444 18579 logs/access.log 0:0:0:8.921 ~ forever list info: Forever processes running data: uid command script forever pid logfile uptime data: [0] SmtT /usr/local/bin/node app.js 18444 18604 logs/access.log 0:0:0:0.177 ~ forever list info: Forever processes running data: uid command script forever pid logfile uptime data: [0] SmtT /usr/local/bin/node app.js 18444 18604 logs/access.log 0:0:0:2.206
这样forever就帮助咱们完成了,几项比较重要服务器管理功能:“启动/中止命令简单”,“支持热部署”,“宕机重启”,“监控界面和日志”。
比起upstart管理,省略了配置脚本的步骤(/etc/init/nodejs-xx.conf)。其余的功能,还要更近一步的使用才知道。
开发环境
~ cd /home/conan/nodejs/nodejs-forever/ ~ forever -p . -l ./logs/access.log -e ./logs/error.log -a -w start app.js
生产环境
~ export LOG=/var/log/nodejs/project ~ export PID=/var/log/nodejs/project/forever.pid ~ export APP_PATH=/home/conan/nodejs/nodejs-forever ~ export APP=$APP_PATH/app.js ~ forever -p $APP_PATH -l $LOG/access.log -e $LOG/error.log -o $LOG/out.log -a --pidFile $PID start $APP