Which SDK version are you using?

v. 7

What's the issue?

ApiNodeList.nextPage requests one additional page even when it's at the last page of results currently.
Documentation in https://developers.facebook.com/docs/graph-api/using-graph-api/#paging states:

Stop paging when the next link no longer appears.

However, in that case ApiNodeList.nextPage falls back to cursor-based paging mechanism and only stops after retrieving an additional empty page with no cursor information.

Steps/Sample code to reproduce the issue

Use any graph edge that returns ApiNodeList like campaigns, that returns one or more pages of data

Observed Results:

• What happened? This could be a description, log output, etc.

For N pages of data, there is N+1 requests beign made. One final request is made when there is no next link, which results in a response with empty data array and no paging section. Only after that paging stops, even though it is apparent from the lack of next page in Nth response that N+1th request is not necessary.

Nth request

2020-09-21 13:06:33.743 ========Start of API Call========
2020-09-21 13:06:33.743 Request:
2020-09-21 13:06:33.743 GET: https://graph.facebook.com/v7.0/act_.../campaigns?acce
ss_token=...&fields=id%2Cname&limit=25&after=QVFIUkhyNWtiM1JJLTk5WEhRaWZAFc0F...&appsecret_proof=...
2020-09-21 13:06:33.831 Response:
2020-09-21 13:06:33.831 {"data":[
<LAST PAGE OF DATA RETURNED HERE>
],"paging":{"cursors":{"before":"QVFIUkVES3hiV0tyUjQ...","after":"QVFIUlJReDdpSDlOcHlGeUYzemhqNDRsYV..."},
"previous":"https:\/\/graph.facebook.com\/v7.0\/act_...\/campaigns?access_token=...&fields=id\u00252Cname&limit=25&before=QVFIUkVES3hi..."}}
2020-09-21 13:06:33.831 ========End of API Call========

N+1th request

2020-09-21 13:06:33.836 ========Start of API Call========
2020-09-21 13:06:33.837 Request:
2020-09-21 13:06:33.837 GET: https://graph.facebook.com/v7.0/act_.../campaigns?acce
ss_token=...&appsecret_proof=...&after=QVFIUlJReDdpSDlOcHlGeUYzemhqNDRsYV...&fields=id%2Cname
2020-09-21 13:06:33.887 Response:
2020-09-21 13:06:33.887 {"data":[]}
2020-09-21 13:06:33.887 ========End of API Call========

Expected Results:

• What did you expect to happen?

ApiNodeList.nextPage should not make the extra (N+1th) request for empty page when it knows from its current state that there was no more data.