Tracks: Replace RwLock<TypeMap> data store with Arc<dyn Any> (serenit…

…y-rs#219)

Cargo.toml

@@ -50,7 +50,6 @@ tracing = { version = "0.1", features = ["log"] }
 tracing-futures = "0.2"
 twilight-gateway = { default-features = false, optional = true, version = "0.15.0" }
 twilight-model = { default-features = false, optional = true, version = "0.15.0" }
-typemap_rev = { optional = true, version = "0.3" }
 url = { optional = true, version = "2" }
 uuid = { features = ["v4"], optional = true, version = "1" }
 
@@ -101,7 +100,6 @@ driver = [
     "dep:tokio",
     "dep:tokio-tungstenite",
     "dep:tokio-util",
-    "dep:typemap_rev",
     "dep:url",
     "dep:uuid",
     "tokio?/fs",

src/lib.rs

@@ -111,8 +111,6 @@ mod ws;
 pub use discortp as packet;
 #[cfg(feature = "driver")]
 pub use serenity_voice_model as model;
-#[cfg(feature = "driver")]
-pub use typemap_rev as typemap;
 
 // Re-export serde-json APIs locally to minimise conditional config elsewhere.
 #[cfg(not(feature = "simd-json"))]

src/tracks/handle.rs

@@ -1,9 +1,7 @@
 use super::*;
 use crate::events::{Event, EventData, EventHandler};
 use flume::{Receiver, Sender};
-use std::{fmt, sync::Arc, time::Duration};
-use tokio::sync::RwLock;
-use typemap_rev::TypeMap;
+use std::{any::Any, sync::Arc, time::Duration};
 use uuid::Uuid;
 
 #[derive(Clone, Debug)]
@@ -19,32 +17,27 @@ pub struct TrackHandle {
     inner: Arc<InnerHandle>,
 }
 
+#[derive(Debug)]
 struct InnerHandle {
     command_channel: Sender<TrackCommand>,
     uuid: Uuid,
-    typemap: RwLock<TypeMap>,
-}
-
-impl fmt::Debug for InnerHandle {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.debug_struct("InnerHandle")
-            .field("command_channel", &self.command_channel)
-            .field("uuid", &self.uuid)
-            .field("typemap", &"<LOCK>")
-            .finish()
-    }
+    data: Arc<dyn Any + Send + Sync + 'static>,
 }
 
 impl TrackHandle {
     /// Creates a new handle, using the given command sink.
     ///
     /// [`Input`]: crate::input::Input
     #[must_use]
-    pub(crate) fn new(command_channel: Sender<TrackCommand>, uuid: Uuid) -> Self {
+    pub(crate) fn new(
+        command_channel: Sender<TrackCommand>,
+        uuid: Uuid,
+        data: Arc<dyn Any + Send + Sync + 'static>,
+    ) -> Self {
         let inner = Arc::new(InnerHandle {
             command_channel,
             uuid,
-            typemap: RwLock::new(TypeMap::new()),
+            data,
         });
 
         Self { inner }
@@ -198,16 +191,22 @@ impl TrackHandle {
         self.inner.uuid
     }
 
-    /// Allows access to this track's attached [`TypeMap`].
+    /// Allows access to this track's attached Data.
     ///
-    /// [`TypeMap`]s allow additional, user-defined data shared by all handles
+    /// Data allows additional, user-defined data shared by all handles
     /// to be attached to any track.
     ///
-    /// Driver code will never attempt to lock access to this map,
-    /// preventing deadlock/stalling.
+    /// # Panics
+    /// This method will panic if the Data has not been initialised, or the type
+    /// provided does not equal the type passed to [`Track::new_with_data`].
     #[must_use]
-    pub fn typemap(&self) -> &RwLock<TypeMap> {
-        &self.inner.typemap
+    pub fn data<Data>(&self) -> Arc<Data>
+    where
+        Data: Send + Sync + 'static,
+    {
+        Arc::clone(&self.inner.data)
+            .downcast()
+            .expect("TrackHandle::data generic does not match type set in TrackHandle::set_data")
     }
 
     #[inline]

src/tracks/mod.rs

@@ -41,7 +41,7 @@ pub use self::{
 pub(crate) use command::*;
 
 use crate::{constants::*, driver::tasks::message::*, events::EventStore, input::Input};
-use std::time::Duration;
+use std::{any::Any, sync::Arc, time::Duration};
 use uuid::Uuid;
 
 /// Initial state for audio playback.
@@ -104,27 +104,45 @@ pub struct Track {
     ///
     /// Defaults to a random 128-bit number.
     pub uuid: Uuid,
+
+    /// Any data to be associated with the track.
+    pub user_data: Arc<dyn Any + Send + Sync>,
 }
 
 impl Track {
     /// Create a new track directly from an [`Input`] and a random [`Uuid`].
     #[must_use]
     pub fn new(input: Input) -> Self {
-        let uuid = Uuid::new_v4();
-
-        Self::new_with_uuid(input, uuid)
+        Self::new_with_uuid(input, Uuid::new_v4())
     }
 
     /// Create a new track directly from an [`Input`] with a custom [`Uuid`].
     #[must_use]
     pub fn new_with_uuid(input: Input, uuid: Uuid) -> Self {
+        Self::new_with_uuid_and_data(input, uuid, Arc::new(()))
+    }
+
+    /// Create a new track directly from an [`Input`], user data to be associated with the track, and a random [`Uuid`].
+    #[must_use]
+    pub fn new_with_data(input: Input, user_data: Arc<dyn Any + Send + Sync + 'static>) -> Self {
+        Self::new_with_uuid_and_data(input, Uuid::new_v4(), user_data)
+    }
+
+    /// Create a new track directly from an [`Input`], user data to be associated with the track, and a custom [`Uuid`].
+    #[must_use]
+    pub fn new_with_uuid_and_data(
+        input: Input,
+        uuid: Uuid,
+        user_data: Arc<dyn Any + Send + Sync + 'static>,
+    ) -> Self {
         Self {
             playing: PlayMode::default(),
             volume: 1.0,
             input,
             events: EventStore::new_local(),
             loops: LoopState::Finite(0),
             uuid,
+            user_data,
         }
     }
 
@@ -180,7 +198,7 @@ impl Track {
 
     pub(crate) fn into_context(self) -> (TrackHandle, TrackContext) {
         let (tx, receiver) = flume::unbounded();
-        let handle = TrackHandle::new(tx, self.uuid);
+        let handle = TrackHandle::new(tx, self.uuid, self.user_data.clone());
 
         let context = TrackContext {
             handle: handle.clone(),