[ARROW-10710] [Rust] Example flight server is broken after tokio upgrade (among other things)

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 3.0.0
• Component/s: Rust
• Labels: pull-request-available
• External issue URL: https://github.com/apache/arrow/issues/26659
• Assignee: Andrew Lamb
• Reporter: Andrew Lamb
• Created: 24/Nov/20 12:32
• Updated: 11/Jan/23 08:15
• Resolved: 25/Nov/20 13:33

Description

As pointed out by rdettai on https://github.com/apache/arrow/pull/8697#issuecomment-732936572

Doing this:

cd rust/arrow-flight; cargo run --example server

results in the following compile error

error: The #[tokio::main] macro requires rt or rt-multi-thread.
   --> arrow-flight/examples/server.rs:121:1
    |
121 | #[tokio::main]
    | ^^^^^^^^^^^^^^
    |
    = note: this error originates in an attribute macro (in Nightly builds, run with -Z macro-backtrace for more info)

warning: unused import: `tonic::transport::Server`
  --> arrow-flight/examples/server.rs:21:5
   |
21 | use tonic::transport::Server;
   |     ^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: `#[warn(unused_imports)]` on by default

warning: unused import: `flight_service_server::FlightServiceServer`
  --> arrow-flight/examples/server.rs:25:43
   |
25 |     flight_service_server::FlightService, flight_service_server::FlightServiceServer,
   |                                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error[E0601]: `main` function not found in crate `server`
   --> arrow-flight/examples/server.rs:18:1
    |
18  | / use std::pin::Pin;
19  | |
20  | | use futures::Stream;
21  | | use tonic::transport::Server;
...   |
130 | |     Ok(())
131 | | }
    | |_^ consider adding a `main` function to `arrow-flight/examples/server.rs`

error: aborting due to 2 previous errors; 2 warnings emitted

Issue Links

• links to: GitHub Pull Request #8769