概要
目前在做個發佈項目,需要一直運行單個Python腳本,以便於對需要發佈的任務進行發佈邏輯操作,並且是在Linux下運行的
目前能想到的方法有兩個:
- Crontab定時
- Systemctl守護進程
最後決定使用Systemctl守護進程來做,一方面是因爲Crontab最小粒度只支持到一分鐘,也就是1分鐘執行1次,而這個腳本需要的實時性較高,7、8秒一次,另一方面,使用守護進程來做的話,一旦掛了能實現重啓進程
方法
release.py後臺常駐運行
以守護進程的方式運行,一旦掛掉自動重啓
需要常駐的腳本:release.py
# -*- coding:utf-8 -*-
import time
# 常駐進程,每8秒執行一個任務的發佈
while 1:
print(time.gmtime())
# Todo 執行操作
run()
# 延時8秒
time.sleep(8)
常駐進程,每8秒執行一次
編寫systemd:
vim /etc/systemd/system/auto_release.service
[Unit]
Description=The python script used for release
After=syslog.target network.target remote-fs.target nss-lookup.target
[Service]
Type=simple
ExecStart=/usr/bin/python3 /data/zaspace/data/AutoRelease/release.py
Restart=on-failure
[Install]
WantedBy=multi-user.target
啓動該腳本並且開機運行
systemctl start auto_release
systemctl enable auto_release
查看該進程的狀態
systemctl status auto_release
運行:
● auto_release.service - The python script used for release
Loaded: loaded (/etc/systemd/system/auto_release.service; disabled; vendor preset: disabled)
Active: active (running) since Tue 2019-08-20 13:46:52 CST; 24h ago
Main PID: 16652 (python3)
CGroup: /system.slice/auto_release.service
└─16652 /usr/bin/python3 /data/zaspace/data/AutoRelease/release.py
Aug 21 14:09:03 zabank-toolset-forward.novalocal python3[16652]: time.struct_time(tm_year=2019, tm_mon=8, tm_mday=21, tm_hour=...t=0)
Aug 21 14:09:03 zabank-toolset-forward.novalocal python3[16652]: time.struct_time(tm_year=2019, tm_mon=8, tm_mday=21, tm_hour=...t=0)
Aug 21 14:09:03 zabank-toolset-forward.novalocal python3[16652]: time.struct_time(tm_year=2019, tm_mon=8, tm_mday=21, tm_hour=...t=0)
Hint: Some lines were ellipsized, use -l to show in full.
[root@zabank-toolset-forward AutoRelease]# systemctl status auto_release
● auto_release.service - The python script used for release
Loaded: loaded (/etc/systemd/system/auto_release.service; disabled; vendor preset: disabled)
Active: active (running) since Tue 2019-08-20 13:46:52 CST; 24h ago
Main PID: 16652 (python3)
CGroup: /system.slice/auto_release.service
└─16652 /usr/bin/python3 /data/zaspace/data/AutoRelease/release.py
Aug 21 14:09:03 zabank-toolset-forward.novalocal python3[16652]: time.struct_time(tm_year=2019, tm_mon=8, tm_mday=21, tm_hour=6, tm_min=7, tm_sec=42, tm_wday=2, tm_yday=233, tm_isdst=0)
Aug 21 14:09:03 zabank-toolset-forward.novalocal python3[16652]: time.struct_time(tm_year=2019, tm_mon=8, tm_mday=21, tm_hour=6, tm_min=7, tm_sec=50, tm_wday=2, tm_yday=233, tm_isdst=0)
Aug 21 14:09:03 zabank-toolset-forward.novalocal python3[16652]: time.struct_time(tm_year=2019, tm_mon=8, tm_mday=21, tm_hour=6, tm_min=7, tm_sec=59, tm_wday=2, tm_yday=233, tm_isdst=0)
上面的輸出結果含義如下:
- Loaded行:配置文件的位置,是否設爲開機啓動
- Active行:表示正在運行
- Main PID行:主進程ID
- Status行:由應用本身(這裏是 httpd )提供的軟件當前狀態
- CGroup塊:應用的所有子進程
- 日誌塊:應用的日誌
注意:如果該Python腳本有更新的話,需要重啓該進程的,不會立即生效的
相關命令
啓動該服務 sudo systemctl start xxx.service
啓動該服務 sudo systemctl restart xxx.service
停止該服務 sudo systemctl stop xxx.service
查看運行狀態 sudo systemctl status xxx.service
設置開機運行 sudo systemctl enable xxx.service
查看是否有啓動該Python腳本
ps -ef | grep python
查看日誌
journalctl -xu auto_release