Re: [Evolution] Moved messages disappear from source, never show in destination

[Milan Crha <mcrha redhat com>]

On Sun, 2016-04-10 at 13:26 +0000, Matthew Saltzman wrote:
> > Bug, or PEBKAC?

        Hi,
it sounds like a bug.

> On further investigation, it seems that what's happening is this:
>  * User selects a block of messages to move that is larger than some
>    internal limit.
>  * As the move process proceeds, the messages are marked deleted from
>    the origin folder, but have not yet been copied to the destination.
>  * The move fails with no notice.
>  * The original state of messages in the origin folder is not restored,
>    so the messages remain invisible in that client.

This investigation is valuable. And I thin it's it. There will be some
error reading issue in the EWS code, because the server should report
that it is not willing to move too many messages at once. I know that I
cannot get a listing of a folder at once if it contains many
(thousands) messages. The server rejects the request with an "I am
busy" error, while I know it's camping. Reading the folder content in
smaller chunks, like by 100 messages, makes the server happy. The
problem with the message move can be similar.

The reason why the Refresh on the folder didn't work is that the EWS
code does incremental updates. Evolution internally "deletes" the
messages (internally like in the local cache), but they are not deleted
on the server. When you call the Refresh, then it asks for the changes
since the last time, but there were none, thus the local cache is left
untouched (messages kept "deleted" locally). When you create a new
account then there is no mark what the previous state was, thus the EWS
code reads real content and shows the messages as the OWA (WEB)
interface. I think it would be good to invalidate local last-state-
marks and refresh the folders from the scratch when the Refresh from
the UI is requested. I think I cannot distinguish that from the folder
context menu, but maybe from the account folder menu it will be
possible (then it'll invalidate all folders and will refresh all of
them when they are entered).

That is, please file two new bug reports against evolution-ews in the
GNOME bugzilla, one for the move, another for the refresh for mail
folders. Ideally send a link to them to the list, for further
reference.

        Thanks and bye,
        Milan