Can you use a Google Sheet as a Shopify webhook URL? What has to sit in between

You cannot directly use a Google Sheet as a Shopify webhook URL. The webhook URL field in Shopify expects a receiver that can receive and process the incoming request. However, there are two ways to route Shopify events to a Google Sheet: using a connector or an Apps Script web app.

The first option is to use a connector such as Zapier, Make, or n8n. These services provide a new URL that you can paste into Shopify's URL field. When Shopify sends an event to this URL, the connector will write the row to the Google Sheet. Note that Zapier's webhook trigger is not available on the Free plan.

The second option is to create a Google Apps Script web app. This method also requires a separate service to handle the incoming requests. An Apps Script web app gets its own URL, and Google's web apps guide explains what happens when a request arrives. The request body is received through the doPost function, and the destination must return an HtmlOutput or TextOutput object. On Shopify's end, a non-200 response can cause an automatic deletion of the webhook subscription.

There is a built-in option in Shopify Flow that adds a route without a webhook URL. The Add row to spreadsheet action writes the row directly to the Google Sheet without needing an incoming URL. This option is available on Basic, Grow, Advanced, and Plus plans. However, Shopify Flow does not support the Send HTTP request action, which would allow using a connector or Apps Script web app.

In summary, Shopify webhooks cannot directly send data to a Google Sheet. You need to use a connector or an Apps Script web app as an intermediary to route the event to the Google Sheet. Keep in mind that using a connector may require a paid plan, while creating an Apps Script web app requires some coding knowledge and careful testing to ensure the webhook subscription remains active.