Another API pagination request for help!

[StephenLis]

Hi

I am using the Canvas LMS API and am struggling with a pagination issue. Using a few tutorials and posts from here I have managed to make some progress but haven’t quite nailed it.

Using the following query I am able to iterate through the pages of the endpoint I’m calling but the query loops endlessly.

let
    Query1 = List.Generate(()=>
[Result = try fComments(1) otherwise null, Page=1],
each [Result] <> null and [Page] < 10,
each [Result = try fComments([Page]+1) otherwise null, Page=[Page]+1],
each [Result])
in
    Query1

To stop this I added the [Page] < 10 condition and it now stops after 9 iterations and I can see the data I expect is being returned. Each call to the endpoint returns a list. The first few lists contain the data I want as expected but subsequent calls return empty lists. Whilst this is usable it is not ideal.

This is what is returned

Using Postman I can confirm that API calls to page numbers that don’t have data don’t return an error but rather return an empty list.

I need a way to add a condition that stops the loop when an empty list is returned but have not been able to work it out. Any help is appreciated.

Thanks

[StephenLis]

Thanks Pat

That worked, greatly appreciated

Cheers

[ppm1 · Accepted solution]

Try changing your condition to the following. 

each List.Count([Result]) > 0 and [Page] < 10

Pat