EXPUNGE may return either a series of EXPUNGE responses each with
a single message sequence number, or a VANISHED response with a
sequence set of UIDs. This adds a wrapper enum and some associated
iterators to make it easy to handle these in the client.
Add support for HIGHESTMODSEQ (RFC 4551) and VANISHED (RFC 7162),
which allows users to quickly synchronize to a mailbox by fetching
only changes since the last known highest mod sequence.
Add a `imap::connect_starttls` convenience function, with the same
syntax as `imap::connect`, to make STARTTLS connections as easily as
IMAPS.
PR#140 removed `imap::connect_insecure` with the stated goal of
encouraging users to connect securely. With that change, users are
forced to construct their own `TcpStream`s when interacting with
non-IMAPS servers.
This change may perversely incentivise the use of insecure connections,
instead of discouraging them, as users may blindly copy-paste code
involving `Client::new` and `TcpStream`s so things "just work", without
the visual indicator of `_insecure` suggesting something is wrong.
Tangentially, [RFC 2595] encourages using STARTTLS instead of raw SSL
sockets. Ideally, we should support both options equally well.
[RFC 2595]: https://tools.ietf.org/html/rfc2595#section-7
In order to discourage folks from connecting securely, we're removing the
convenience method imap::connect_insecure.
Fear not\! For those who manage security in another way (aka a private network
or similar measures), it is still possible to connect without TLS by using the
imap::Client::new() method. See that method for examples of how to do this.
Establishes conditional compilation for all integration with the
native_tls crate in this crate. Since native_tls has been deeply
integrated into this crate for a long time, we want to maintain
backwards compatibility by making this feature part of the default.
For a consumer of this crate to "opt-out", including this in
cargo.toml:
```
[dependencies.imap]
version = 0.16.0 # Replace this with the correct version
default-features = false
```
See the conversation on Github for details on this approach:
https://github.com/jonhoo/rust-imap/issues/123
By checking this code in as an example, we can prevent bitrot as we continuously test this
in CI. It also demonstrates how to setup TLS without relying on platform specific dependencies
via native_tls crate.
