本人初學(xué)shell語言，希望把這幾段if語句合并一下，怎么怎么優(yōu)化？

if [ ! -f "./service/config/setting.js" ];then
    echo "文件不存在"
else
    rm -f ./service/config/setting.js
fi

if [ $USE_LOGIN ]; then
    USE_LOGIN=$USE_LOGIN
else
    USE_LOGIN='http://898101.0.0.1/api/login'
fi

if [ $searchOrdinary ]; then
    searchOrdinary=$searchOrdinary
else
    searchOrdinary='http://127.0.0.1/api/search/common'
fi

if [ $searchLabel ]; then
    searchLabel=$searchLabel
else
    searchLabel='http://127.0.0.1/api/search/common'
fi

if [ $searchVideo ]; then
    searchVideo = $searchVideo
else
    searchVideo='http://127.0.0.1/api/search/common'
fi

if [ $taskManager ]; then
    taskManager=$taskManager
else
    taskManager='http://127.0.0.1/api/search/common'
fi

echo "
    pythonAPI: {

            //userLogin : 'http://10.23.102.148:5002/api/login', // 用戶登陸接口 api
            userLogin : '$USE_LOGIN',
            video: '', //
            searchOrdinary: '$searchOrdinary', // 普通搜索接口
            //searchLabel: '/api/search/result', // 周同標(biāo)簽搜索、圖片搜索
            searchLabel: '$searchLabel',
            searchVideo : '$searchVideo', // 周同標(biāo)簽搜索接口
            taskManager: '$taskManager' // 任務(wù)管理器接口
        };" >> ./service/config/setting.js