src/base.js
function getBucketCors(params, callback) {
    submitRequest.call(this, {
        Action: 'name/cos:GetBucketCORS',
        method: 'GET',
        Bucket: params.Bucket,
        Region: params.Region,
        headers: params.Headers,
        action: 'cors',
    }, function (err, data) {
        if (err) {
            if (err.statusCode === 404 && err.error && err.error.Code === 'NoSuchCORSConfiguration') {
                var result = {
                    CORSRules: [],
                    statusCode: err.statusCode,
                };
                err.headers && (result.headers = err.headers);
                callback(null, result);
            } else {
                callback(err);
            }
            return;
        }
        var CORSConfiguration = data.CORSConfiguration || {};
        var CORSRules = CORSConfiguration.CORSRules || CORSConfiguration.CORSRule || [];
        CORSRules = util.clone(util.isArray(CORSRules) ? CORSRules : [CORSRules]);

        util.each(CORSRules, function (rule) {
            util.each(['AllowedOrigin', 'AllowedHeader', 'AllowedMethod', 'ExposeHeader'], function (key, j) {
                var sKey = key + 's';
                var val = rule[sKey] || rule[key] || [];
                delete rule[key];
                rule[sKey] = util.isArray(val) ? val : [val];
            });
        });

        callback(null, {
            CORSRules: CORSRules,
            statusCode: data.statusCode,
            headers: data.headers,
        });
    });
}
function getBucketCors(params, callback) {
    submitRequest.call(this, {
        Action: 'name/cos:GetBucketCORS',
        method: 'GET',
        Bucket: params.Bucket,
        Region: params.Region,
        headers: params.Headers,
        action: 'cors',
    }, function (err, data) {
        if (err) {
            if (err.statusCode === 404 && err.error && err.error.Code === 'NoSuchCORSConfiguration') {
                var result = {
                    CORSRules: [],
                    statusCode: err.statusCode,
                };
                err.headers && (result.headers = err.headers);
                callback(null, result);
            } else {
                callback(err);
            }
            return;
        }
        var CORSConfiguration = data.CORSConfiguration || {};
        var CORSRules = CORSConfiguration.CORSRules || CORSConfiguration.CORSRule || [];
        CORSRules = util.clone(util.isArray(CORSRules) ? CORSRules : [CORSRules]);

        util.each(CORSRules, function (rule) {
            util.each(['AllowedOrigin', 'AllowedHeader', 'AllowedMethod', 'ExposeHeader'], function (key, j) {
                var sKey = key + 's';
                var val = rule[sKey] || rule[key] || [];
                delete rule[key];
                rule[sKey] = util.isArray(val) ? val : [val];
            });
        });

        callback(null, {
            CORSRules: CORSRules,
            statusCode: data.statusCode,
            headers: data.headers,
        });
    });
}
获取 Bucket 的 跨域设置
@param  {Object}  params                         参数对象，必须
@param  {String}  params.Bucket              Bucket名称，必须
@param  {String}  params.Region              地域名称，必须
@param  {Function}  callback                     回调函数，必须
@return  {Object}  err                           请求失败的错误，如果请求成功，则为空。https://cloud.tencent.com/document/product/436/7730
@return  {Object}  data                          返回的数据
@return  {Object}  data.CORSRules            Bucket的跨域设置