Comment 5 for bug 1638769

At the moment, we don't properly handle the case when new providers are installed on the system: the client will continue seeing the old provider's list. You can file a bug for that, but I don't think this is a critical issue.

The client retrieve the provider list (along with the existing accounts list) when the Manager gets initialized, and we assume that this list doesn't change. The RequestAccess() method and the AccountChanged signal only carry the serviceId field, which can then be used to look up the provider information in the provider list (which also contains the serviceId). Give that the you might have several accounts for the same provider, we are not replicating the provider information for each account.
However, this should not be a concern of the client, since the client library already tooks care of resolving the mapping (if it doesn't, please file a bug).

To quickly test the new API, you can get the Account Tester app from https://wiki.ubuntu.com/Process/Merges/TestPlan/ubuntu-system-settings-online-accounts (version 0.15, it's the one linked in the "provider-data" test case).

for testing with gdbus, remember that you need to pass the applicationId as parameter to the GetAccounts call (you can omit it, if you are a confined app).