We're currently working on a solution that uses the .NET library for the API.
With the API we're getting all clients from an account (approx. 95 clients), and each client has their own List. So we're getting out a approx. 95 lists that the user can subscribe or unsubscribe to. So for this we're making a lot of API calls; first for getting all clients and then for getting the newsletter list from each client. And it taking quite a while to load the web application because of all these calls.
We also have a feature for the client to edit their subscription. This feature lets them view the same list again of approx. 95 clients with their list, where they see a checkbox next to each list which is either checked or not depending whether they've subscribed to it before or not.
This means that for each of the approx. 95 Lists we're showing we have to make another API call to check if the email address has subscribed to that specific List. Hereby we end with about 191 API calls for getting our list and giving them a way to edit their subscription. This takes about 40 seconds to load.
My question is then: Do you have idea or suggestion on how we could speed up this process?
Hope it all makes sense, otherwise just ask. Thanks in advance! :)
Note: The reason we've set it up as clients instead of simply a lot of lists in one, is that our client has a lot of stores, and each store needs to be able to only manage their own newsletters.
Note 2: We can't hard code a list of all list ids and then list them, as the list of clients can change.