adding callback for reusable credentials (librespot-org#983)

This allows more control over how the credentials are saved to the cache

CHANGELOG.md

@@ -16,6 +16,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - [playback] `Sink`: `write()` now receives ownership of the packet (breaking).
 - [playback] `pipe`: create file if it doesn't already exist
 - [playback] More robust dynamic limiter for very wide dynamic range (breaking)
+- [core] `Session`: `connect()` now returns the long-term credentials.
+- [core] `Session`: `connect()` now accespt a flag if the credentails should be stored via the cache.
 - [build] The MSRV is now 1.53.
 
 ### Added

core/src/session.rs

@@ -66,7 +66,8 @@ impl Session {
         config: SessionConfig,
         credentials: Credentials,
         cache: Option<Cache>,
-    ) -> Result<Session, SessionError> {
+        store_credentials: bool,
+    ) -> Result<(Session, Credentials), SessionError> {
         let ap = apresolve(config.proxy.as_ref(), config.ap_port).await;
 
         info!("Connecting to AP \"{}\"", ap);
@@ -76,18 +77,20 @@ impl Session {
             connection::authenticate(&mut conn, credentials, &config.device_id).await?;
         info!("Authenticated as \"{}\" !", reusable_credentials.username);
         if let Some(cache) = &cache {
-            cache.save_credentials(&reusable_credentials);
+            if store_credentials {
+                cache.save_credentials(&reusable_credentials);
+            }
         }
 
         let session = Session::create(
             conn,
             config,
             cache,
-            reusable_credentials.username,
+            reusable_credentials.username.clone(),
             tokio::runtime::Handle::current(),
         );
 
-        Ok(session)
+        Ok((session, reusable_credentials))
     }
 
     fn create(

core/tests/connect.rs

@@ -13,6 +13,7 @@ async fn test_connection() {
             SessionConfig::default(),
             Credentials::with_password("test", "test"),
             None,
+            false,
         )
         .await;
 

examples/get_token.rs

@@ -20,7 +20,7 @@ async fn main() {
 
     println!("Connecting..");
     let credentials = Credentials::with_password(&args[1], &args[2]);
-    let session = Session::connect(session_config, credentials, None)
+    let (session, _) = Session::connect(session_config, credentials, None, false)
         .await
         .unwrap();
 

examples/play.rs

@@ -27,7 +27,7 @@ async fn main() {
     let backend = audio_backend::find(None).unwrap();
 
     println!("Connecting ..");
-    let session = Session::connect(session_config, credentials, None)
+    let (session, _) = Session::connect(session_config, credentials, None, false)
         .await
         .unwrap();
 

examples/playlist_tracks.rs

@@ -27,7 +27,7 @@ async fn main() {
         process::exit(1);
     });
 
-    let session = Session::connect(session_config, credentials, None)
+    let (session, _) = Session::connect(session_config, credentials, None, false)
         .await
         .unwrap();
 

src/main.rs

@@ -1599,6 +1599,7 @@ async fn main() {
                 setup.session_config.clone(),
                 credentials,
                 setup.cache.clone(),
+                true,
             )
             .fuse(),
         );
@@ -1634,6 +1635,7 @@ async fn main() {
                             setup.session_config.clone(),
                             credentials,
                             setup.cache.clone(),
+                            true,
                         ).fuse());
                     },
                     None => {
@@ -1643,7 +1645,7 @@ async fn main() {
                 }
             },
             session = &mut connecting, if !connecting.is_terminated() => match session {
-                Ok(session) => {
+                Ok((session,_)) => {
                     let mixer_config = setup.mixer_config.clone();
                     let mixer = (setup.mixer)(mixer_config);
                     let player_config = setup.player_config.clone();
@@ -1711,6 +1713,7 @@ async fn main() {
                             setup.session_config.clone(),
                             credentials,
                             setup.cache.clone(),
+                            true
                         ).fuse());
                     },
                     _ => {