Simple LIST command fails with Gmail

[theduke]

Hey there.

I'm trying to LIST all mailboxes with Gmail.

Connecting works fine, but executing the list command results in weird "Unknown command" errors.

NOTE: the value for the command changes with each invocation.

 INFO 2018-07-16T14:19:51Z: mycloudbackup::service::email: listing mailboxes...
thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: BadResponse("Unknown command q4-v6mb43737048lth")

stack backtrace:
   0:     0x55ab9a875425 - backtrace::backtrace::libunwind::trace::hf612167c3b0ad921
                        at /home/theduke/.cargo/registry/src/jackfan.us.kg-1ecc6299db9ec823/backtrace-0.3.9/src/backtrace/libunwind.rs:53
                         - backtrace::backtrace::trace::h574c6ad167c02b7c
                        at /home/theduke/.cargo/registry/src/jackfan.us.kg-1ecc6299db9ec823/backtrace-0.3.9/src/backtrace/mod.rs:42
   1:     0x55ab9a870c5e - backtrace::capture::Backtrace::new_unresolved::hfc2f37046d10e114
                        at /home/theduke/.cargo/registry/src/jackfan.us.kg-1ecc6299db9ec823/backtrace-0.3.9/src/capture.rs:88
   2:     0x55ab9a86f037 - failure::backtrace::internal::InternalBacktrace::new::h50a420eea00b0a25
                        at /home/theduke/.cargo/registry/src/jackfan.us.kg-1ecc6299db9ec823/failure-0.1.1/src/backtrace/internal.rs:44
   3:     0x55ab9a86e7dc - failure::backtrace::Backtrace::new::ha4994e8172e6037b
                        at /home/theduke/.cargo/registry/src/jackfan.us.kg-1ecc6299db9ec823/failure-0.1.1/src/backtrace/mod.rs:98
   4:     0x55ab9a6e4d4d - <failure::error::Error as core::convert::From<F>>::from::h2008397b91b24e51
                        at /home/theduke/.cargo/registry/src/jackfan.us.kg-1ecc6299db9ec823/failure-0.1.1/src/error.rs:34
   5:     0x55ab9a6e4852 - mycloudbackup::service::email::EmailService::run::h09ca1ab1e24544f2
                        at src/service/email/mod.rs:40
   6:     0x55ab9a6e6a3e - mycloudbackup::main::h1b5295b517f21400
                        at src/main.rs:30
   7:     0x55ab9a6e3e7f - std::rt::lang_start::{{closure}}::hf04d67d357e8192d
                        at /checkout/src/libstd/rt.rs:74
   8:     0x55ab9a95a2e2 - std::rt::lang_start_internal::{{closure}}::h72602870b4a34363
                        at libstd/rt.rs:59
                         - std::panicking::try::do_call::hc2917ab2c572e22d
                        at libstd/panicking.rs:310
   9:     0x55ab9a973239 - __rust_maybe_catch_panic
                        at libpanic_unwind/lib.rs:105
  10:     0x55ab9a95f4f5 - std::panicking::try::h3777f1f99a655493
                        at libstd/panicking.rs:289
                         - std::panic::catch_unwind::hab6d1467193fc938
                        at libstd/panic.rs:374
                         - std::rt::lang_start_internal::h106bcdfb2e3beaf8
                        at libstd/rt.rs:58
  11:     0x55ab9a6e3e57 - std::rt::lang_start::hfacb80090f7d05a5
                        at /checkout/src/libstd/rt.rs:74
  12:     0x55ab9a6e6adc - main
  13:     0x7fa1a55b306a - __libc_start_main
  14:     0x55ab9a6dc369 - _start
  15:                0x0 - <unknown>', libcore/result.rs:945:5
stack backtrace:
   0: std::sys::unix::backtrace::tracing::imp::unwind_backtrace
             at libstd/sys/unix/backtrace/tracing/gcc_s.rs:49
   1: std::sys_common::backtrace::print
             at libstd/sys_common/backtrace.rs:71
             at libstd/sys_common/backtrace.rs:59
   2: std::panicking::default_hook::{{closure}}
             at libstd/panicking.rs:211
   3: std::panicking::default_hook
             at libstd/panicking.rs:227
   4: std::panicking::rust_panic_with_hook
             at libstd/panicking.rs:463
   5: std::panicking::begin_panic_fmt
             at libstd/panicking.rs:350
   6: rust_begin_unwind
             at libstd/panicking.rs:328
   7: core::panicking::panic_fmt
             at libcore/panicking.rs:71
   8: core::result::unwrap_failed
             at /checkout/src/libcore/macros.rs:26
   9: <core::result::Result<T, E>>::unwrap
             at /checkout/src/libcore/result.rs:782
  10: mycloudbackup::main
             at src/main.rs:30
  11: std::rt::lang_start::{{closure}}
             at /checkout/src/libstd/rt.rs:74
  12: std::panicking::try::do_call
             at libstd/rt.rs:59
             at libstd/panicking.rs:310
  13: __rust_maybe_catch_panic
             at libpanic_unwind/lib.rs:105
  14: std::rt::lang_start_internal
             at libstd/panicking.rs:289
             at libstd/panic.rs:374
             at libstd/rt.rs:58
  15: std::rt::lang_start
             at /checkout/src/libstd/rt.rs:74
  16: main
  17: __libc_start_main
  18: _start

        let ssl_connector = TlsConnector::builder()?.build()?;
        let socket_addr = (conf.domain.as_str(), conf.socket);
        let mut imap = Client::secure_connect(socket_addr, &conf.domain, &ssl_connector)?;

        // List all folders.
        info!("listing mailboxes...");
        let folders = imap.list("", "*")?;
        println!("{:#?}", folders);

[theduke]

Turns out I forgot to call client.login(...).

Is there a smoother way to detect a missing login and produce an approrpiate error?

[jonhoo]

Hmm, yes, in theory we could differentiate this using types. We could give you an UnauthenticatedClient when you call connect (or secure_connect), and then have login consume self and produce a Client. It'd be a pretty major API change, but I have some other changes along those lines I've wanted to make too, so I think it's a good idea. I'm sort of waiting on #69, since without that I have relatively little agency in publishing changes :)

[dario23]

@jonhoo +1 for the UnauthenticatedClient/Client idea, i had a small step in that direction too, some time ago