自动更新GitHubHosts

此方法并不能适用于SNI阻断场景

#!/bin/bash  
# byzhao
# This is the basic bash script  
export LANG=zh_CN.UTF-8
request_log=/home/byzhao/github_hosts.log
download_file=/etc/hosts.download

sudo curl -s -o "$download_file" https://raw.hellogithub.com/hosts >/dev/null 2>&1  
if [ $? -eq 0 ]; then  
        echo "文件下载成功....."
        start_num=$(awk '/GitHub520 Host Start/ {print NR; exit}' /etc/hosts)
        end_num=$(awk '/GitHub520 Host End/ {last_match_line=NR} END {print last_match_line}' /etc/hosts)

        if [ -n "${start_num}" ] && [ -n "${end_num}"  ]; then
                echo "解析文件行: ${start_num}, ${end_num}"

                # 删除对应行  
                if sudo sed -i "${start_num},${end_num}d" /etc/hosts; then  
                        echo "删除原github hosts"  
                else  
                        echo "删除原github hosts失败"  
                        exit 1  
                fi
        fi
        # 追加新的hosts到/etc/hosts
        if sudo sh -c "cat $download_file >> /etc/hosts"; then  
            echo "追加新的hosts"  
        else  
            echo "追加新的hosts失败"  
            exit 1  
        fi  

        sudo rm -f "{$download_file}"
        echo "删除临时文件"
        curl -X "POST" "http://xxx.xxx.cn:8081/wuaFrBQHBvF25bbPEt69Mg" -H 'Content-Type: application/json; charset=utf-8' -d '{"title": "GitHub","body": "hosts更新完成","group": "GitHub"}'
        echo "完成..."
else  
  echo "下载失败"  
fi