Pagination for Google Apps Script with Shopify API - api

Question

I am running into a bit of a snag setting up pagination in Google Apps Script. I am trying to use it for Shopify API. Reference links attached.
I attached the code below of what I have so far -
trying to figure out how to use the "While" statement to make it check if there is a Next Page URL
trying to figure out a way to parse the Link in the header. Example below. On pages 2+ there will be a next and previous link. We only need the next
https://shop-domain.myshopify.com/admin/api/2019-07/products.json?limit=50&page_info=eyJkaXJlY3Rpb24iOiJwcmV2IiwibGFzdF9pZCI6MTk4NTgyMTYzNCwibGFzdF92YWx1ZSI6IkFjcm9saXRoaWMgQWx1bWludW0gUGVuY2lsIn0%3D; rel="previous", https://shop-domain.myshopify.com/admin/api/2019-07/products.json?limit=50&page_info=eyJkaXJlY3Rpb24iOiJuZXh0IiwibGFzdF9pZCI6MTk4NTgzNjU0NiwibGFzdF92YWx1ZSI6IkFoaXN0b3JpY2FsIFZpbnlsIEtleWJvYXJkIn0%3D; rel="next
function callShopifyOrderCount() {
var accessToken = 'xxxx';
var store_url = 'https://xxxx.myshopify.com/admin/api/2021-01/orders.json?status=any&fields=created_at,id,name,total-price&limit=20';
var headers = {
"Content-Type": "application/json",
'X-Shopify-Access-Token': accessToken
};
var options = {
"method": "GET",
"headers": headers,
"contentType": "application/json",
"muteHttpExceptions": true,
}
var response = UrlFetchApp.fetch(store_url, options)
// Call the link header for next page
var header = response.getHeaders()
var linkHeader = header.Link;
var responseCode = response.getResponseCode();
var responseBody = response.getContentText();
if (responseCode === 200) {
var responseJson = JSON.parse(responseBody);
var objectLength = responseJson.orders.length;
for (var i = 0; i < objectLength; i++) {
var orderId = responseJson.orders[i].id;
var orderPrice = responseJson.orders[i].total_price;
var orderName = responseJson.orders[i].name;
}
} else {
Logger.log(
Utilities.formatString(
"First Request failed. Expected 200, got %d: %s",
responseCode,
responseBody
)
);
// ...
}
// *** NEED TO FIGURE OUT WHILE STATEMENT //
while (Link != null) {
var store_url = linkHeader;
var response = UrlFetchApp.fetch(store_url, options)
var responseCode = response.getResponseCode();
var responseBody = response.getContentText();
var header = response.getHeaders()
var linkHeader = header.Link;
if (responseCode === 200) {
var responseJson = JSON.parse(responseBody);
var objectLength = responseJson.orders.length;
for (var i = 0; i < tweetLength; i++) {
var orderId = responseJson.orders[i].id;
var orderPrice = responseJson.orders[i].total_price;
var orderName = responseJson.orders[i].name;
}
}
else {
Logger.log(
Utilities.formatString(
"Second Request failed. Expected 200, got %d: %s",
responseCode,
responseBody
)
);
}
}
}
References:
https://shopify.dev/tutorials/make-paginated-requests-to-rest-admin-api
https://www.shopify.com/partners/blog/relative-pagination