react native react-native-sync-localstorage code example

Example: react-native-sync-localstorage expire date

/**
 *
 * @param urlAsKey
 * @param expireInMinutes
 * @returns {Promise.<*>}
 */
async getCachedUrlContent(urlAsKey, expireInMinutes = 60) {

    let data = null;

    await AsyncStorage.getItem(urlAsKey, async (err, value) => {

        data = (JSON.parse(value));

        // there is data in cache && cache is expired
        if (data !== null && data['expireAt'] &&
            new Date(data.expireAt) < (new Date())) {

            //clear cache
            AsyncStorage.removeItem(urlAsKey);


            //update res to be null
            data = null;
        } else {

            console.log('read data from cache  ');

        }
    });

    //update cache + set expire at date
    if (data === null) {
        console.log('cache new Date ');

        //fetch data
        data = fetch(urlAsKey).then((response) => response.json())
            .then(apiRes => {

                //set expire at
                apiRes.expireAt = this.getExpireDate(expireInMinutes);

                //stringify object
                const objectToStore = JSON.stringify(apiRes);

                //store object
                AsyncStorage.setItem(urlAsKey, objectToStore);


                console.log(apiRes.expireAt);
                return apiRes;
            });

    }

    return data;


},

/**
 *
 * @param expireInMinutes
 * @returns {Date}
 */
getExpireDate(expireInMinutes) {
    const now = new Date();
    let expireTime = new Date(now);
    expireTime.setMinutes(now.getMinutes() + expireInMinutes);
    return expireTime;
}