This set of commits add import from local accounts.
It's a bit rough around the edges, but it's good enough to go in, so work can continue
collaboratively.
The crypto class now behaves differently depending on the version of the
journal.
The current difference is in the key derivation, and that the new
version of the crypto also hmacs the version automatically whenever it
hmacs anything.
The versioning was added for better future-proofing of the code.
The derivation change was done because before we were creating the same
password for all of the journals, now we do it per-journal. This means
that we can, if needed in the future use this password as the journal
password when sharing journals without compromising the security of the
rest of the journals.
The app update broadcast receiver is only called on the first update,
not install, which was causing EteSync to think it was updating from
version 1 on the first update, doesn't matter which version one was
updating from.
This fixes it by saving the version on the first run.
Before this change we were adding them to cache before they were
processed, potentially persisting malformed entries, or entries we
haven't yet processed causing issues if sync was aborted before an entry
was fully processed.
Commit 5d1c90dcba fixed a bug where
entries added from the server were marked as "local only" (null etag)
which was causing issues. That commit fixes it for newly added resources,
but existing resources remained broken.
This commit goes through the database and fixes all of the existing
broken resources. It skips dirty entries because figuring out if they
were just created or updated is complex, and the chances of doing an
update at exactly the same time there are dirty entries is quite low,
so the complexity involved is just not worth it.
Before this commit we would create new entries from the server without
an etag, essentially marking them as "local only". While the actual
value of the eTag is not currently used, null or not matters.
Because the resources were "local only", we would get weird behaviours
like having an "ADD" action when changing a resource.
Before this change we would only add "deletes" to the server when the
resource has been previously uploaded. This means that if a resource has
been created and then deleted before a sync, it would not be saved,
which is essentially data-loss.
This commit fixes it, so we always upload a delete entry.
It's really annoying that it doesn't do it automatically as it should,
in the meanwhile, add this workaround.
I reported it to upstream:
https://github.com/requery/requery/issues/487
Clearing the cache is a good idea regardless, though because of the
unique constraints in the cache on the journal name, this was causing
issues when deleting an account and then adding it back.
