Failed to build when using rustls instead of OpenSSL in rusoto_core

[Observer42]

🐛 Bug description

Failed to build when using rustls instead of OpenSSL in rusoto_core
the error message is:

   Compiling rusoto_core v0.37.0
error[E0259]: the name `tls` is defined multiple times
  --> /home/yishengxu/.cargo/registry/src/github.heygears.com-1ecc6299db9ec823/rusoto_core-0.37.0/src/lib.rs:28:1
   |
26 | extern crate hyper_rustls as tls;
   | --------------------------------- previous import of the extern crate `tls` here
27 | #[cfg(feature = "native-tls")]
28 | extern crate hyper_tls as tls;
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `tls` reimported here
   |
   = note: `tls` must be defined only once in the type namespace of this module
help: you can use `as` to change the binding name of the import
   |
28 | extern crate hyper_tls as other_tls;
   |

error[E0308]: mismatched types
   --> /home/yishengxu/.cargo/registry/src/github.heygears.com-1ecc6299db9ec823/rusoto_core-0.37.0/src/request.rs:328:13
    |
327 |         let connector = match HttpsConnector::new(4) {
    |                               ---------------------- this match expression has type `tls::HttpsConnector<hyper::client::HttpConnector>`
328 |             Ok(connector) => connector,
    |             ^^^^^^^^^^^^^ expected struct `tls::HttpsConnector`, found enum `std::result::Result`
    |
    = note: expected type `tls::HttpsConnector<hyper::client::HttpConnector>`
               found type `std::result::Result<_, _>`

error[E0308]: mismatched types
   --> /home/yishengxu/.cargo/registry/src/github.heygears.com-1ecc6299db9ec823/rusoto_core-0.37.0/src/request.rs:329:13
    |
327 |         let connector = match HttpsConnector::new(4) {
    |                               ---------------------- this match expression has type `tls::HttpsConnector<hyper::client::HttpConnector>`
328 |             Ok(connector) => connector,
329 |             Err(tls_error) => {
    |             ^^^^^^^^^^^^^^ expected struct `tls::HttpsConnector`, found enum `std::result::Result`
    |
    = note: expected type `tls::HttpsConnector<hyper::client::HttpConnector>`
               found type `std::result::Result<_, _>`

error[E0308]: mismatched types
   --> /home/yishengxu/.cargo/registry/src/github.heygears.com-1ecc6299db9ec823/rusoto_core-0.37.0/src/request.rs:346:13
    |
345 |         let connector = match HttpsConnector::new(4) {
    |                               ---------------------- this match expression has type `tls::HttpsConnector<hyper::client::HttpConnector>`
346 |             Ok(connector) => connector,
    |             ^^^^^^^^^^^^^ expected struct `tls::HttpsConnector`, found enum `std::result::Result`
    |
    = note: expected type `tls::HttpsConnector<hyper::client::HttpConnector>`
               found type `std::result::Result<_, _>`

error[E0308]: mismatched types
   --> /home/yishengxu/.cargo/registry/src/github.heygears.com-1ecc6299db9ec823/rusoto_core-0.37.0/src/request.rs:347:13
    |
345 |         let connector = match HttpsConnector::new(4) {
    |                               ---------------------- this match expression has type `tls::HttpsConnector<hyper::client::HttpConnector>`
346 |             Ok(connector) => connector,
347 |             Err(tls_error) => {
    |             ^^^^^^^^^^^^^^ expected struct `tls::HttpsConnector`, found enum `std::result::Result`
    |
    = note: expected type `tls::HttpsConnector<hyper::client::HttpConnector>`
               found type `std::result::Result<_, _>`

error: aborting due to 5 previous errors

Some errors occurred: E0259, E0308.
For more information about an error, try `rustc --explain E0259`.
error: Could not compile `rusoto_core`.

🤔 Expected Behavior

build without problem

👟 Steps to reproduce

1. create a new cargo project
2. add following dependencies to the project:

rusoto_core = {version = "0.37.0", default_features = false, features = ["rustls"]}
dynomite = "0.3"

3. run cargo build

if I change dependencies to

rusoto_core = "0.37.0"
dynomite = "0.3"

or remove dynomite dependency
the build will not fail

🌍 Your environment

x86_64
ubuntu 18.04

dynomite version:
0.3.0

rustc version:
stable 1.34

[jeprojects]

Same issue here.

[jeprojects]

@softprops Any chance you could add a feature to dynomite to switch rusoto to use the rustls dependancy instead of the default openssl?

[softprops]

I think that may have the same effect for those using rusoto defaults.

Wouldn't they they run into the same issue if dynamite defaulted to rusttls and rusoto core defaulted to openssl?

It seems like the kind of thing where you'd want to opt in at the application level and have a way to use a non default consistently.