Groups are saved as separate vCards. We removed support for groups to
speed up development and deferred adding them back until there was
demand.
There is demand now, and also, not having this support resulted in the
sync not working, not just groups not supported.
Many thanks to "359" (this user's preferred alias) for investigating and
reporting this issue.
Due to a logical issue in the code, new journal entries were added to the
local cache after they've been created locally, and not after they've
been added to the server. Under normal circumstances this doesn't pose a
problem, however when pushing to the server fails, the local cache
would have the new entries as if they were saved on the server, causing
the app to think there has been a corruption on the server (as entries
should never be removed from the server) and halt the sync.
This change makes it so the entries are saved to the local cache only
after they've been saved on the server.
Note: this was not spotted until now because it relies on an unfortunate
specific sequence of events. It only happens when creating journal
entries, and when trying to sync them successfully connecting to the
server to fetch the journal list and the content of the journal itself,
and only failing when coming to push the journals.
Many thanks to "359" (this user's preferred alias) for reporting the
issue that resulted in this fix.
I assumed the lifecycle of the fragment and the task were tied because they
are tied to the instance, but it looks like I was wrong. We need to
explicitly cancel tasks.
This patch changes the fetching so if the last fetch returned less entries
than the limit, we don't try and fetch again because we already know there
are no others left.
Before this commit we used to fetch the whole journal entry list in one
go, which caused issues in two cases:
1. On slow internet connections the download may fail.
2. With big journals: Android interrupts sync managers if they don't
perform any significant network traffic for over a minute[1],
and because we would first download and only then process, we would
sometimes hit this threshold.
Current chunk size is set to 50.
1: https://developer.android.com/reference/android/content/AbstractThreadedSyncAdapter.html
I set it to 2048 following the NIST recommendations[1] which said it was
OK, but actually, as pointed out by Dominik Schürmann, it's probably a
better idea to set to 3072.
Users who already have a 2048 key pair won't be affected, while users
who don't will have a 3072 key created for them. Users with different
key lengths can interact with each other without any issues.
1: https://www.keylength.com/en/4/
