Shell practice: one click start process, close process and view process status

All the way to Databend Take the program as an example to practice

Databend Official documents ：https://databend.rs/doc
The driving force of practice ： Manual start 、 close 、 It's too troublesome to check the status , Go straight up Shell Script ( Add execution permission manually chmod +x xx.sh)

One button start

involves ：command Splicing

path="/usr/bin/databend/bin"
${path}/databend-meta -c ./configs/databend-meta.toml > meta.log 2>&1 &
${path}/databend-query -c ./configs/databend-query.toml > query.log 2>&1 &

---

One button closure

Knowledge points involved ：

1. Array operation （ Take the length of the array ）
2. String segmentation （ adopt for loop ）
3. Before selection n That's ok （head command ）
4. Select the first n Column （awk command , The content is huge ）
5. Arithmetic syntax
6. if Process control

# get pid list
ls=`ps -elf | grep databend | head -n 2 | awk '{print $4}'`
#  Cut string 
len=0
for pid in ${ls[*]}
do
    pids[len]=$pid
    len=`expr $len + 1`
    # echo ${pid}
done
# pids The array length is greater than 1
if [ ${
    #pids[@]} -gt 1 ]
then
    for i in ${pids[*]}
    do
        kill -9 ${i}
    done
    echo "databend is stoped"
else
    echo "databend no starting"
fi

---

One click View

echo '----------server-status-------------'
curl -I  http://127.0.0.1:8101/v1/health
curl -I  http://127.0.0.1:8001/v1/health
echo '----------process-info-------------'
ps -elf | grep databend