如何保证你的小应用长生不死

美好的愿望

通常我们在部署spring-boot应用的时候，
总希望应用能够好好活着。
即使出现了内存溢出或者被别人把应用给杀死了，
也希望应用能够快速自动重新启动起来。
下面就介绍一款能满足我们需求的小工具。

Supervisor

官方地址：
http://www.supervisord.org/

安装

这里我们介绍比较方便的一种安装方式 pip 安装。
因为Supervisor不支持Python3，因此需要在Python2的环境下进行安装。

pip install supervisor

安装完毕后，可以通过下面的命令来查看和创建配置文件

查看配置文件，顺便看看是否安装成功了

echo_supervisord_conf

配置

配置文件中有很多项目我一般比较关心下面的几项

file=/tmp/supervisor.sock   ; the path to the socket file 建议修改
logfile=/tmp/supervisord.log ; main log file; default $CWD/supervisord.log 建议修改
pidfile=/tmp/supervisord.pid ; supervisord pidfile; default supervisord.pid 建议修改
serverurl=unix:///tmp/supervisor.sock ; use a unix:// URL  for a unix socket  建议修改, 位置如上设定
;files = relative/directory/*.ini  建议修改，并解消注释

建议把我们的配置都归纳到一个文件夹，方便进行统一的管理

# 想知道Mac下面这个树如何生成的？先安装一个查看目录树的小工具  brew install tree
# rest.gehui.com.ini 是我们的一个应用的配置，稍后介绍
supervisor
├── conf
│   └── rest.gehui.com.ini
├── logs
├── start.sh
├── supervisorctl.sh
├── supervisord.ini
└── temp

这里面的几个文件的详情

start.sh

#!/bin/sh

/usr/local/bin/supervisord -c "/Users/gehui/work/supervisor/supervisord.ini"

supervisorctl.sh

#!/bin/sh

/usr/local/bin/supervisorctl -c "/Users/gehui/work/supervisor/supervisord.ini" $@

supervisord.ini

; Sample supervisor config file.
;
; For more information on the config file, please see:
; http://supervisord.org/configuration.html
;
; Notes:
;  - Shell expansion ("~" or "$HOME") is not supported.  Environment
;    variables can be expanded using this syntax: "%(ENV_HOME)s".
;  - Quotes around values are not supported, except in the case of
;    the environment= options as shown below.
;  - Comments must have a leading space: "a=b ;comment" not "a=b;comment".
;  - Command will be truncated if it looks like a config file comment, e.g.
;    "command=bash -c 'foo ; bar'" will truncate to "command=bash -c 'foo ".

[unix_http_server]
file=/Users/gehui/work/supervisor/temp/supervisor.sock   ; the path to the socket file 自定义
;chmod=0700                 ; socket file mode (default 0700)
;chown=nobody:nogroup       ; socket file uid:gid owner
;username=user              ; default is no username (open server)
;password=123               ; default is no password (open server)

[inet_http_server]         ; inet (TCP) server disabled by default
port=127.0.0.1:9001        ; ip_address:port specifier, *:port for all iface
username=admin             ; default is no username (open server)  自定义
password=Passw0rd          ; default is no password (open server)  自定义

[supervisord]
logfile=/Users/gehui/work/supervisor/logs/supervisord.log ; main log file; default $CWD/supervisord.log 自定义
logfile_maxbytes=50MB        ; max main logfile bytes b4 rotation; default 50MB
logfile_backups=10           ; # of main logfile backups; 0 means none, default 10
loglevel=info                ; log level; default info; others: debug,warn,trace
pidfile=/Users/gehui/work/supervisor/temp/supervisord.pid ; supervisord pidfile; default supervisord.pid 自定义
nodaemon=false               ; start in foreground if true; default false
minfds=1024                  ; min. avail startup file descriptors; default 1024
minprocs=200                 ; min. avail process descriptors;default 200
;umask=022                   ; process file creation umask; default 022
;user=chrism                 ; default is current user, required if root
;identifier=supervisor       ; supervisord identifier, default is 'supervisor'
;directory=/tmp              ; default is not to cd during start
;nocleanup=true              ; don't clean up tempfiles at start; default false
;childlogdir=/tmp            ; 'AUTO' child log dir, default $TEMP
;environment=KEY="value"     ; key value pairs to add to environment
;strip_ansi=false            ; strip ansi escape codes in logs; def. false

; The rpcinterface:supervisor section must remain in the config file for
; RPC (supervisorctl/web interface) to work.  Additional interfaces may be
; added by defining them in separate [rpcinterface:x] sections.

[rpcinterface:supervisor]
supervisor.rpcinterface_factory = supervisor.rpcinterface:make_main_rpcinterface

; The supervisorctl section configures how supervisorctl will connect to
; supervisord.  configure it match the settings in either the unix_http_server
; or inet_http_server section.

[supervisorctl]
serverurl=unix:///Users/gehui/work/supervisor/temp/supervisor.sock ; use a unix:// URL  for a unix socket 自定义
serverurl=http://127.0.0.1:9001 ; use an http:// url to specify an inet socket 自定义
;username=chris              ; should be same as in [*_http_server] if set
;password=123                ; should be same as in [*_http_server] if set
;prompt=mysupervisor         ; cmd line prompt (default "supervisor")
;history_file=~/.sc_history  ; use readline history if available

; The sample program section below shows all possible program subsection values.
; Create one or more 'real' program: sections to be able to control them under
; supervisor.

;[program:theprogramname]
;command=/bin/cat              ; the program (relative uses PATH, can take args)
;process_name=%(program_name)s ; process_name expr (default %(program_name)s)
;numprocs=1                    ; number of processes copies to start (def 1)
;directory=/tmp                ; directory to cwd to before exec (def no cwd)
;umask=022                     ; umask for process (default None)
;priority=999                  ; the relative start priority (default 999)
;autostart=true                ; start at supervisord start (default: true)
;startsecs=1                   ; # of secs prog must stay up to be running (def. 1)
;startretries=3                ; max # of serial start failures when starting (default 3)
;autorestart=unexpected        ; when to restart if exited after running (def: unexpected)
;exitcodes=0,2                 ; 'expected' exit codes used with autorestart (default 0,2)
;stopsignal=QUIT               ; signal used to kill process (default TERM)
;stopwaitsecs=10               ; max num secs to wait b4 SIGKILL (default 10)
;stopasgroup=false             ; send stop signal to the UNIX process group (default false)
;killasgroup=false             ; SIGKILL the UNIX process group (def false)
;user=chrism                   ; setuid to this UNIX account to run the program
;redirect_stderr=true          ; redirect proc stderr to stdout (default false)
;stdout_logfile=/a/path        ; stdout log path, NONE for none; default AUTO
;stdout_logfile_maxbytes=1MB   ; max # logfile bytes b4 rotation (default 50MB)
;stdout_logfile_backups=10     ; # of stdout logfile backups (0 means none, default 10)
;stdout_capture_maxbytes=1MB   ; number of bytes in 'capturemode' (default 0)
;stdout_events_enabled=false   ; emit events on stdout writes (default false)
;stderr_logfile=/a/path        ; stderr log path, NONE for none; default AUTO
;stderr_logfile_maxbytes=1MB   ; max # logfile bytes b4 rotation (default 50MB)
;stderr_logfile_backups=10     ; # of stderr logfile backups (0 means none, default 10)
;stderr_capture_maxbytes=1MB   ; number of bytes in 'capturemode' (default 0)
;stderr_events_enabled=false   ; emit events on stderr writes (default false)
;environment=A="1",B="2"       ; process environment additions (def no adds)
;serverurl=AUTO                ; override serverurl computation (childutils)

; The sample eventlistener section below shows all possible eventlistener
; subsection values.  Create one or more 'real' eventlistener: sections to be
; able to handle event notifications sent by supervisord.

;[eventlistener:theeventlistenername]
;command=/bin/eventlistener    ; the program (relative uses PATH, can take args)
;process_name=%(program_name)s ; process_name expr (default %(program_name)s)
;numprocs=1                    ; number of processes copies to start (def 1)
;events=EVENT                  ; event notif. types to subscribe to (req'd)
;buffer_size=10                ; event buffer queue size (default 10)
;directory=/tmp                ; directory to cwd to before exec (def no cwd)
;umask=022                     ; umask for process (default None)
;priority=-1                   ; the relative start priority (default -1)
;autostart=true                ; start at supervisord start (default: true)
;startsecs=1                   ; # of secs prog must stay up to be running (def. 1)
;startretries=3                ; max # of serial start failures when starting (default 3)
;autorestart=unexpected        ; autorestart if exited after running (def: unexpected)
;exitcodes=0,2                 ; 'expected' exit codes used with autorestart (default 0,2)
;stopsignal=QUIT               ; signal used to kill process (default TERM)
;stopwaitsecs=10               ; max num secs to wait b4 SIGKILL (default 10)
;stopasgroup=false             ; send stop signal to the UNIX process group (default false)
;killasgroup=false             ; SIGKILL the UNIX process group (def false)
;user=chrism                   ; setuid to this UNIX account to run the program
;redirect_stderr=false         ; redirect_stderr=true is not allowed for eventlisteners
;stdout_logfile=/a/path        ; stdout log path, NONE for none; default AUTO
;stdout_logfile_maxbytes=1MB   ; max # logfile bytes b4 rotation (default 50MB)
;stdout_logfile_backups=10     ; # of stdout logfile backups (0 means none, default 10)
;stdout_events_enabled=false   ; emit events on stdout writes (default false)
;stderr_logfile=/a/path        ; stderr log path, NONE for none; default AUTO
;stderr_logfile_maxbytes=1MB   ; max # logfile bytes b4 rotation (default 50MB)
;stderr_logfile_backups=10     ; # of stderr logfile backups (0 means none, default 10)
;stderr_events_enabled=false   ; emit events on stderr writes (default false)
;environment=A="1",B="2"       ; process environment additions
;serverurl=AUTO                ; override serverurl computation (childutils)

; The sample group section below shows all possible group values.  Create one
; or more 'real' group: sections to create "heterogeneous" process groups.

;[group:thegroupname]
;programs=progname1,progname2  ; each refers to 'x' in [program:x] definitions
;priority=999                  ; the relative start priority (default 999)

; The [include] section can just contain the "files" setting.  This
; setting can list multiple files (separated by whitespace or
; newlines).  It can also contain wildcards.  The filenames are
; interpreted as relative to this file.  Included files *cannot*
; include files themselves.

[include]
files = /Users/gehui/work/supervisor/conf/*.ini    ; 自定义

创建spring-boot应用

# 不妨先复习一下shell
mkdir -p /Users/gehui/work/rest.gehui.com

# 应用结构如下

rest.gehui.com
├── bin
│   └── rest.gehui.com-1.0.jar
├── logs
├── start.sh
└── temp

启动文件 start.sh

#!/bin/bash

BASE_DIR=/Users/gehui/work/rest.gehui.com
BUILD_NAME=1.0

exec /Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/bin/java \
-Dfile.encoding=UTF-8 \
-Xmx128m \
-XX:+UseG1GC \
-XX:MaxGCPauseMillis=100 \
-XX:InitiatingHeapOccupancyPercent=35 \
-verbose:gc \
-XX:+PrintGCDetails \
-XX:+PrintGCDateStamps \
-XX:+PrintGCTimeStamps \
-XX:+PrintGCApplicationStoppedTime \
-Xloggc:${BASE_DIR}/logs/jvm_gc.log \
-XX:ErrorFile=${BASE_DIR}/logs/jvm_err.log \
-XX:+HeapDumpOnOutOfMemoryError \
-XX:HeapDumpPath=${BASE_DIR}/logs/jvm_dump_pid%p.hprof \
-jar ${BASE_DIR}/bin/rest.gehui.com-${BUILD_NAME}.jar \
# --spring.profiles.active=production

运行一下看看～

chmod 775 start.sh
# 执行一下看看
./start.sh

# 换个iTerm tab试试效果，搞定！
curl "http://localhost:8080/greeting"
{"id":1,"content":"Hello, World!"}%

配置应用管理

如上文提到的，创建一个我们的spring-boot服务配置文件：

rest.gehui.com.ini

[program:rest.gehui.com]
command=/Users/gehui/work/rest.gehui.com/start.sh              ; the program (relative uses PATH, can take args)
;;process_name=%(program_name)s ; process_name expr (default %(program_name)s)
;;numprocs=1                    ; number of processes copies to start (def 1)
directory=/Users/gehui/work/rest.gehui.com                ; directory to cwd to before exec (def no cwd)
;;umask=022                     ; umask for process (default None)
;;priority=999                  ; the relative start priority (default 999)
autostart=true                  ; start at supervisord start (default: true)
;;startsecs=1                   ; # of secs prog must stay up to be running (def. 1)
;;startretries=3                ; max # of serial start failures when starting (default 3)
;;autorestart=unexpected        ; when to restart if exited after running (def: unexpected)
;;exitcodes=0,2                 ; 'expected' exit codes used with autorestart (default 0,2)
;;stopsignal=QUIT               ; signal used to kill process (default TERM)
;;stopwaitsecs=10               ; max num secs to wait b4 SIGKILL (default 10)
;;stopasgroup=false             ; send stop signal to the UNIX process group (default false)
;;killasgroup=false             ; SIGKILL the UNIX process group (def false)
;;user=user_00                  ; setuid to this UNIX account to run the program
redirect_stderr=true            ; redirect proc stderr to stdout (default false)
stdout_logfile=/Users/gehui/work/rest.gehui.com/logs/supervisord-std.log        ; stdout log path, NONE for none; default AUTO
stdout_logfile_maxbytes=10MB    ; max # logfile bytes b4 rotation (default 50MB)
stdout_logfile_backups=10       ; # of stdout logfile backups (0 means none, default 10)
;;stdout_capture_maxbytes=1MB   ; number of bytes in 'capturemode' (default 0)
;;stdout_events_enabled=false   ; emit events on stdout writes (default false)
;;stderr_logfile=/Users/gehui/work/rest.gehui.com/logs/supervisord-stderr.log        ; stderr log path, NONE for none; default AUTO
;;stderr_logfile_maxbytes=10MB  ; max # logfile bytes b4 rotation (default 50MB)
;;stderr_logfile_backups=10     ; # of stderr logfile backups (0 means none, default 10)
;;stderr_capture_maxbytes=1MB   ; number of bytes in 'capturemode' (default 0)
;;stderr_events_enabled=false   ; emit events on stderr writes (default false)
;;environment=A="1",B="2"       ; process environment additions (def no adds)
;;serverurl=AUTO                ; override serverurl computation (childutils)

启动我们的Supervisor

# 注意设置一下shell脚本的执行权限
cd /Users/gehui/work/supervisor
./start.sh

启动完服务的端口号为：127.0.0.1:9001，看看服务的状态

./supervisorctl.sh status
rest.gehui.com                   RUNNING   pid 11434, uptime 0:00:05

也可以登录 http://127.0.0.1:9001/ 来查看状态，管理页面比较简单易懂，在此不再赘述。

看看应用是否能够访问

curl "http://localhost:8080/greeting"
{"id":1,"content":"Hello, World!"}%

# 杀死他
kill -9 11434

# 再看看
curl "http://localhost:8080/greeting"
curl: (7) Failed to connect to localhost port 8080: Connection refused

# 马上再看一次，又自动活过来了～
curl "http://localhost:8080/greeting"
{"id":1,"content":"Hello, World!"}%

成功！