Box: フォルダに電子すかし適用

main();
function main(){
    const oauth2 = configs.get('conf_OAuth2');
    const folderId = decideFolderId();
    applyWatermark(oauth2, folderId);
}

/**
  * フォルダ ID を config から読み出して出力する
  * @return {String} folderId フォルダ ID
  */
function decideFolderId(){
    const folderId = engine.findData(configs.getObject('conf_FolderId'));
    if (folderId === '' || folderId === null) {
        throw 'Folder ID is blank.';
    }
    return folderId;
}

/**
  * 電子すかしを適用
  * @param {String} oauth OAuth2 設定
  * @param {String} folderId フォルダ ID
  */
function applyWatermark(oauth2, folderId) {
    const jsonBody = {};
    jsonBody['watermark'] = {'imprint': 'default'};
    const url = `https://api.box.com/2.0/folders/${encodeURIComponent(folderId)}/watermark`;
    const response = httpClient.begin()
        .authSetting(oauth2)
        .body(JSON.stringify(jsonBody), 'application/json; charset=UTF-8')
        .put(url);
    const status = response.getStatusCode();
    if (status !== 200 && status !== 201) { // 200: 更新, 201: 新規適用
        engine.log(response.getResponseAsString());
        throw `Failed to apply watermark. status:${status}`;
    }
}