function getRepositoryContents(arg,cb){
    let masterTreeSHA;
    getLatestMasterTreeSha(arg,(master)=>{

        masterTreeSHA = master['commit']['commit']['tree']['sha'];
        let options = {
            method:"GET",
            url: arg.baseRepoApiUrl+'/git/trees/'+masterTreeSHA+'?recursive=1',
            headers: {
                'Authorization': arg.keyStr
            }
        };
        request(options, (error, response, body) =>{
            if(!error){
                cb(JSON.parse(body));
            }else {
                console.log("can't fetch latest tree ")
            }
        });
    });
}

function getLatestMasterTreeSha(arg, cb){
    let options = {
        method:"GET",
        url: arg.baseRepoApiUrl+'/branches/master',
        headers: {
            'Authorization': arg.keyStr
        }
    };
    request(options, (error, response, body) =>{
        if(!error){
            cb(JSON.parse(body));
        }else {
            console.log("can't fetch latest master commit ")
        }
    });
}