Fix upstream breakage in TLS example.

A breaking change in `tracing` (see tracing#3309) resulted in the TLS
example breaking. This commit implements the work-around in the issue.

Author: SergioBenitez

examples/tls/src/main.rs

@@ -1,10 +1,12 @@
 #[macro_use]
 extern crate rocket;
+extern crate self as tracing;
 
 #[cfg(test)]
 mod tests;
 mod redirector;
 
+use rocket::tracing::*;
 use rocket::mtls::Certificate;
 use rocket::listener::Endpoint;
 

examples/tls/src/redirector.rs

@@ -2,9 +2,9 @@
 
 use std::net::SocketAddr;
 
-use rocket::http::uri::{Origin, Host};
-use rocket::tracing::{self, Instrument};
 use rocket::{Rocket, Ignite, Orbit, State, Error};
+use rocket::http::uri::{Origin, Host};
+use rocket::tracing::Instrument;
 use rocket::fairing::{Fairing, Info, Kind};
 use rocket::response::Redirect;
 use rocket::listener::tcp::TcpListener;
@@ -39,7 +39,7 @@ impl Redirector {
     // Launch an instance of Rocket than handles redirection on `self.port`.
     pub async fn try_launch(self, config: Config) -> Result<Rocket<Ignite>, Error> {
         rocket::span_info!("HTTP -> HTTPS Redirector" => {
-            info!(from =  self.0, to = config.tls_addr.port(),  "redirecting");
+            info!(from = self.0, to = config.tls_addr.port(),  "redirecting");
         });
 
         let addr = SocketAddr::new(config.tls_addr.ip(), self.0);