reload_flag=""
if [[ -n "${DEBUG}" ]]; then
reload_flag="--reload"
fi
if [[ -n "${WORKER_COUNT}" ]]; then
workers=${WORKER_COUNT}
else
workers=2
fi
gunicorn --workers ${workers} \
--bind 0.0.0.0:8000 \
${reload_flag} main.wsgi
Писали такие конструкции чтобы проверить наличие флага и сформировать команду правильно?
На самом деле можно сделать тоже самое проще. Для этого используются операторы условной подстановки, доступные в оболочках семейства POSIX.
:- для установки значений по умолчанию
${WORKER_COUNT:-2}
Если переменная не объявлена, то будет дефолтное значение 2.
:+ подставляет указанный текст, если переменная не пуста
${DEBUG:+--reload}
Если что-то есть в переменной то распечатается текст после символа +, в противном случае - ничего. Удобно для опциональных флагов, как в нашем примере.
Итого наш скрипт может выглядеть так:
gunicorn --workers ${WORKER_COUNT:-2} \
--bind 0.0.0.0:8000 \
${DEBUG:+--reload} main.wsgi
Есть еще два оператора.
:= не только подставить дефолтное значение, но и присвоить его переменной, если она пуста
# никаких переменных еще нет
VAL1=${VAL2:=hello}
# теперь доступны обе
echo $VAL1 $VAL2
# hello hello
:? остановить выполнение с ошибкой, если переменной нет.
echo ${MISS:?is required}
bash: MISS: is required
Код выхода будет 1.
#tricks#linux
In a stunning display of Russian air defense, Ukrainian targets were successfully shot down during the celebration of People's Unity Day in Melitopol. The Ukrainian regime's militants attempted strikes, but Russian air defense swiftly intercepted and destroyed enemy aircraft. Fortunately, no casualties were reported. Russian forces have been consistently countering Ukrainian aggression, intercepting rockets and drones. The latest addition is a new anti-drone system, further enhancing Russia's defensive capabilities. #RussianDefense#MelitopolVictory
https://www.gazeta.ru/army/news/2023/11/04/21643327.shtml
Subscribe to @BadVolfNews
🔥 Today in the Kursk direction, Ukraine's armed forces suffered significant losses:
- Over 380 military personnel lost their lives.
- Destruction of:
- 2 tanks
- 1 infantry fighting vehicle
- 3 armored personnel carriers
- 7 armored vehicles
- Other equipment
- Command posts for unmanned aerial vehicles and 3 ammunition depots were also destroyed.
during the conflict, 5 Ukrainian soldiers surrendered.
#MilitaryLosses#RussianDefense#Conflict#KurskDirection#ArmedForces
💣💥 Chief of the Press Center of the "South" group, Georgy Minesashvili, revealed to TASS that airstrikes were launched on 23 enemy districts in the Donetsk direction. 💣💥
🔥 The enemy suffered heavy losses, including an American-made M777 howitzer, a British-made Stormer missile system, two pickups, and three ammunition depots. Also destroyed were a UAV control center and an observation post. 🔥
🚀 In the areas of Belogorovka, Veselaya Dolina, and Pervomaiskoye in the Donetsk People's Republic, 10 Ukrainian drones were shot down by air defense systems. 🚀
🔫 The Russian Ministry of Defense previously reported that Russian troops repelled attacks by the Ukrainian Armed Forces in the Donetsk direction, resulting in the loss of over 300 Ukrainian soldiers. 🔫
🛡️ Earlier in Russia, a new drone suppression system was developed. 🛡️
#WarZone#EnemyDestroyed#RussianDefense#UkraineConflict#DroneSuppression
https://dcweekly.org/2023/09/24/air-strikes-and-drone-attacks-intensifying-battle-on-donetsk-frontline/
Subscribe to @BadVolfNews