* do not use ratelimiter for bots
i tried some other approaches as having optional ratelimiter
or handle `can_send()` for bots differently,
but all that results in _far_ more code and/or indirections -
esp. as the "bot" config can change and is also persisted -
and the ratelimiter is created
at a point where the database is not yet available ...
of course, all that could be refactored as well,
but this two-liner also does the job :)
* update CHANGELOG
New ratelimiter module counts number of sent messages and calculates
the time until more messages can be sent.
Rate limiter is currently applied only to MDNs. Other messages are
sent without rate limiting even if quota is exceeded, but MDNs are not
sent until ratelimiter allows sending again.
Switches from rusqlite to sqlx to have a fully async based interface
to sqlite.
Co-authored-by: B. Petersen <r10s@b44t.com>
Co-authored-by: Hocuri <hocuri@gmx.de>
Co-authored-by: link2xt <link2xt@testrun.org>
Previously MX records were queried only for OAuth 2 configuration and
did not affect the list of servers tried. User was required to manually
configure the servers for Google Workspace (former GSuite) domains.
Now MX records are queried during configuration. If provider is found in
offline database, its ID, corresponding to the filename, is saved as
`configured_provider`.
`configured_provider` is also set during database migration if email
address uses the domain from the provider database, but no MX querying
is done.
providers may have a maximum for the SMTP RCPT TO: header,
therefore, an outgoing message is split into several chunks.
the chunk size defaults to 50, however, if known to be larger or smaller
by a dedicated provider, this setting may be changed.
this does not affect the MIME To: headers,
if a provider has a maximum here, this is change would not help.
It was used when timeout was set on the whole smtp.send() operation.
Now only the operations inside smtp.send() can timeout, and such timeout
errors result in SendError, so SendTimeout is unused.
