Let the thread load new messages. This may happen when user switches
the setting to delete messages on the server on and there are a lot of
messages to delete.
This prevents generation of a large number of jobs when IMAP deletion
setting is enabled for the first time. Writing jobs to the database
locks it for readers and may cause UI freezing, because chatlist and
messages can't be read until all jobs are written.
Note that on failure job will be written to the database, to make sure
it is postponed instead of being retried immediately.
Job::new() can be used to create jobs in-memory
Job.update() is replaced with Job.save() which can create new database
entries and consumes Job to avoid the need to update job ID after saving
it to the database.
MarkseenMdnOnImap stored server folder and UID which are never updated
by update_server_uid. Now hidden entries are created for MDNs, so they
should be handled as ordinary messages.
This may result in messages not being deleted. Optimization and
traffic-saving is postponed for later, one idea is to optimize message
deletion to avoid checking if Message-ID on the server matches
Message-ID in the database.
If job returns Status::Finished, it will be deleted. Then
add_imap_deletion_jobs will recreate it immediately if the message is
expired. To actually backoff the job, we should postpone it instead of
removing.
This is to avoid creating thousands of jobs when user enables
"delete_server_after" setting for the first time.
If device is offline for more than 2 weeks, some messages may not be
deleted.
When "delete_server_after" setting is configured, postponed
DeleteMsgOnImap jobs are created for incoming messages.
This commit adds job::add_imap_deletion_jobs function which creates
DeleteMsgOnImap jobs right before performing IMAP jobs. This way even
messages that expired when the setting was disabled are going to be
deleted.
Job creation on message reception is unnecessary now, and even harmful
because it will create jobs with an expiration time which may later be
reduced. It is planned to be removed in following commits.
Now 0 means "never delete", 1 means "delete at once" and other values
indicate the number of seconds after which them message should be
deleted from the server.
Configuration value interpretation is moved into
Context.get_config_delete_server_after() function.
Currently only trashed or hidden messages are deleted by
DeleteMsgOnImap, so it is safe to remove database records.
It is planned to delete messages on IMAP server after
user-configurable time to cleanup the server even for messages
displayed in chats. For such messages, we unlink them from the
Message-ID, but keep the database record to display them.
Mutable UID reference is removed. Instead, ImapActionResult is
returned immediately.
If message has changed and UID does not correspond to expected
message, ImapActionResult::Failed is returned. Temprorary IMAP errors
result in ImapActionResult::RetryLater.
On the job side, ImapActionResult::RetryLater does not result in
immediate job retry anymore. Instead, job is retried with a backoff.
