抓取github最新軟體版本

這裡以抓取frp為例

#!/bin/bash
frp_version=$(wget --no-check-certificate -qO- https://api.github.com/repos/fatedier/frp/releases | grep -o '"tag_name": ".*"' |head -n 1| sed 's/"//g;s/v//g'| sed 's/tag_name: //g')
echo ${frp_version}

程式碼解釋

抓取網頁程式碼

wget --no-check-certificate -qO- https://api.github.com/repos/fatedier/frp/releases 

過濾掉除了tag_names那行的內容

grep -o '"tag_name": ".*"'   

顯示結果

"tag_name": "v0.20.0" "tag_name": "v0.19.1" "tag_name": "v0.19.0" "tag_name": "v0.18.0" "tag_name": "v0.17.0" "tag_name": "v0.16.1" "tag_name": "v0.16.0" "tag_name": "v0.15.1" "tag_name": "v0.15.0" "tag_name": "v0.14.1" "tag_name": "v0.14.0" "tag_name": "v0.13.0" "tag_name": "v0.12.0" "tag_name": "v0.11.0" "tag_name": "v0.10.0" "tag_name": "v0.9.3" "tag_name": "v0.9.2" "tag_name": "v0.9.1" "tag_name": "v0.9.0" "tag_name": "v0.8.1" "tag_name": "v0.8.0" "tag_name": "v0.7.0" "tag_name": "v0.6.0" "tag_name": "v0.5.0" "tag_name": "v0.3.0" "tag_name": "v0.2.0" "tag_name": "v0.1.0"

重新排列順序，只顯示數字最大那行

head -n 1                    

顯示結果

"tag_name": "v0.20.0"

搜尋雙引號，並去除雙引號

sed 's/"//g;s/v//g'          

顯示結果

tag_name: 0.20.0

搜尋tag_name: ，並去除tag_name

sed 's/tag_name: //g'        

顯示結果

0.20.0

結論就是不斷的過濾，再將程式碼透過 | 傳送給下一段指令進行更精細的過濾