CreateSession returns EOS_InvalidParameters on first run

[xuelongmu]

Environment

Project Version: 0.0.3
EOS SDK Version: 1.7.0
Unreal Engine Version: 4.24.3

Other software/plugins that *might* be the cause of the issue?

Steps to reproduce

1. Login via AccountPortal
2. Create new session with following settings in FOnlineSessionSettings:

    NumPublicConnections = 4;
    NumPrivateConnections=0;
    bAllowJoinInProgress = true;
    bAllowInvites = true;
    bUsesPresence = true;
    bAllowJoinViaPresence = true;
    bAllowJoinViaPresenceFriendsOnly = false;
    bUsesStats = false;

and set BucketId from FString input parameter:
NewSessionSettings->Set(FName("BucketId"), BucketId, EOnlineDataAdvertisementType::ViaOnlineServiceAndPing);
3. Call CreateSession with the settings.

Expected behaviour

Successful creation of new session.

Actual behaviour

On first run, we get the error
[2020.07.17-04.41.49:918][733]LogOnlineSession: Warning: OSS: Cannot update setting: bUsesPresence - Error Code: EOS_InvalidParameters

The error occurs in the CreateSessionModificationHandle method of OnlineSessionInterfaceEpic. Specifically, on the following call to the EOS SDK:
eosResult = EOS_SessionModification_AddAttribute(ModificationHandle, &attrOpts);

On a hunch, I also tried to reorder the sequence of adding attributes, so that NumPublicConnections comes first, but with the same result.

On the second run, the session is created successfully.

[Ruhrpottpatriot]

Hmm... I can't reproduce the error. And while I found a small bug that the bShouldAdvertise parameter is stored as bUsesPresence I can successfully create the session. Could you provide a minimal working example and upload it to GoogleDrive/Dropbox/Onedrive/etc. ?

[xuelongmu]

EOSDebugging.zip

I've uploaded a minimal working example here (without the Config or Plugins folders). The other bugs that I reported can also be found here. In order to use it, open the DefaultMap where there's a BP_MultiplayerTester actor on the level, and Play. The I key will login, O key will logout, N key will create a new session, and F key will find sessions. Let me know if this works, thanks!

[Ruhrpottpatriot]

I quickly ran you sample and I can create a session and it also shows on the EOS Dashboard as the following image shows:

I have an important meeting tomorrow and I'll look into it in more detail after that.

[xuelongmu]

Were you able to find the created session afterwards using the FindSessions method?

Also, were you able to create the session on the very first try, or did you have to run it twice?

[Ruhrpottpatriot]

Haven't tested a FindSession, but it shows up in the web interface on the first try.

[xuelongmu]

I was also able to see it in the web interface without issue, but had no luck retrieving it with FindSessions.

[Ruhrpottpatriot]

I'll look into FindSessions tomorrow.

[Ruhrpottpatriot]

So I cannot reproduce the session creation bug. With your minimal working example everything works as expected. I can also not confirm #41, at least not like you wrote the bug report, I can however confirm another bug regarding to finding sessions.