Remove unsafe code (#940)

Remove unsafe code

CHANGELOG.md

@@ -28,6 +28,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - [main] Prevent hang when discovery is disabled and there are no credentials or when bad credentials are given.
 - [main] Don't panic when parsing options. Instead list valid values and exit.
 - [main] `--alsa-mixer-device` and `--alsa-mixer-index` now fallback to the card and index specified in `--device`.
+- [core] Removed unsafe code (breaking)
 
 ### Removed
 - [playback] `alsamixer`: previously deprecated option `mixer-card` has been removed.

core/src/cache.rs

@@ -351,12 +351,17 @@ impl Cache {
     }
 
     fn file_path(&self, file: FileId) -> Option<PathBuf> {
-        self.audio_location.as_ref().map(|location| {
+        match file.to_base16() {
-            let name = file.to_base16();
+            Ok(name) => self.audio_location.as_ref().map(|location| {
                 let mut path = location.join(&name[0..2]);
                 path.push(&name[2..]);
                 path
-        })
+            }),
+            Err(e) => {
+                warn!("Invalid FileId: {}", e.utf8_error());
+                None
+            }
+        }
     }
 
     pub fn file(&self, file: FileId) -> Option<File> {

core/src/spotify_id.rs

@@ -2,6 +2,7 @@
 
 use std::convert::TryInto;
 use std::fmt;
+use std::string::FromUtf8Error;
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 pub enum SpotifyAudioType {
@@ -136,7 +137,7 @@ impl SpotifyId {
 
     /// Returns the `SpotifyId` as a base16 (hex) encoded, `SpotifyId::SIZE_BASE16` (32)
     /// character long `String`.
-    pub fn to_base16(&self) -> String {
+    pub fn to_base16(&self) -> Result<String, FromUtf8Error> {
         to_base16(&self.to_raw(), &mut [0u8; SpotifyId::SIZE_BASE16])
     }
 
@@ -144,7 +145,7 @@ impl SpotifyId {
     /// character long `String`.
     ///
     /// [canonically]: https://developer.spotify.com/documentation/web-api/#spotify-uris-and-ids
-    pub fn to_base62(&self) -> String {
+    pub fn to_base62(&self) -> Result<String, FromUtf8Error> {
         let mut dst = [0u8; 22];
         let mut i = 0;
         let n = self.id;
@@ -182,10 +183,7 @@ impl SpotifyId {
 
         dst.reverse();
 
-        unsafe {
+        String::from_utf8(dst.to_vec())
-            // Safety: We are only dealing with ASCII characters.
-            String::from_utf8_unchecked(dst.to_vec())
-        }
     }
 
     /// Returns a copy of the `SpotifyId` as an array of `SpotifyId::SIZE` (16) bytes in
@@ -202,7 +200,7 @@ impl SpotifyId {
     /// be encoded as `unknown`.
     ///
     /// [Spotify URI]: https://developer.spotify.com/documentation/web-api/#spotify-uris-and-ids
-    pub fn to_uri(&self) -> String {
+    pub fn to_uri(&self) -> Result<String, FromUtf8Error> {
         // 8 chars for the "spotify:" prefix + 1 colon + 22 chars base62 encoded ID  = 31
         // + unknown size audio_type.
         let audio_type: &str = self.audio_type.into();
@@ -210,9 +208,10 @@ impl SpotifyId {
         dst.push_str("spotify:");
         dst.push_str(audio_type);
         dst.push(':');
-        dst.push_str(&self.to_base62());
+        let base62 = self.to_base62()?;
+        dst.push_str(&base62);
 
-        dst
+        Ok(dst)
     }
 }
 
@@ -220,7 +219,7 @@ impl SpotifyId {
 pub struct FileId(pub [u8; 20]);
 
 impl FileId {
-    pub fn to_base16(&self) -> String {
+    pub fn to_base16(&self) -> Result<String, FromUtf8Error> {
         to_base16(&self.0, &mut [0u8; 40])
     }
 }
@@ -233,12 +232,12 @@ impl fmt::Debug for FileId {
 
 impl fmt::Display for FileId {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        f.write_str(&self.to_base16())
+        f.write_str(&self.to_base16().unwrap_or_default())
     }
 }
 
 #[inline]
-fn to_base16(src: &[u8], buf: &mut [u8]) -> String {
+fn to_base16(src: &[u8], buf: &mut [u8]) -> Result<String, FromUtf8Error> {
     let mut i = 0;
     for v in src {
         buf[i] = BASE16_DIGITS[(v >> 4) as usize];
@@ -246,10 +245,7 @@ fn to_base16(src: &[u8], buf: &mut [u8]) -> String {
         i += 2;
     }
 
-    unsafe {
+    String::from_utf8(buf.to_vec())
-        // Safety: We are only dealing with ASCII characters.
-        String::from_utf8_unchecked(buf.to_vec())
-    }
 }
 
 #[cfg(test)]
@@ -366,7 +362,7 @@ mod tests {
                 audio_type: c.kind,
             };
 
-            assert_eq!(id.to_base62(), c.base62);
+            assert_eq!(id.to_base62().unwrap(), c.base62);
         }
     }
 
@@ -389,7 +385,7 @@ mod tests {
                 audio_type: c.kind,
             };
 
-            assert_eq!(id.to_base16(), c.base16);
+            assert_eq!(id.to_base16().unwrap(), c.base16);
         }
     }
 
@@ -415,7 +411,7 @@ mod tests {
                 audio_type: c.kind,
             };
 
-            assert_eq!(id.to_uri(), c.uri);
+            assert_eq!(id.to_uri().unwrap(), c.uri);
         }
     }
 

metadata/src/lib.rs

@@ -7,12 +7,12 @@ extern crate log;
 extern crate async_trait;
 
 pub mod cover;
-
 use std::collections::HashMap;
+use std::string::FromUtf8Error;
 
 use librespot_core::mercury::MercuryError;
 use librespot_core::session::Session;
-use librespot_core::spotify_id::{FileId, SpotifyAudioType, SpotifyId};
+use librespot_core::spotify_id::{FileId, SpotifyAudioType, SpotifyId, SpotifyIdError};
 use librespot_protocol as protocol;
 use protobuf::Message;
 
@@ -83,10 +83,16 @@ trait AudioFiles {
 #[async_trait]
 impl AudioFiles for Track {
     async fn get_audio_item(session: &Session, id: SpotifyId) -> Result<AudioItem, MercuryError> {
+        match id.to_base62() {
+            Err(e) => {
+                warn!("Invalid Track SpotifyId: {}", e);
+                Err(MercuryError)
+            }
+            Ok(uri) => {
                 let item = Self::get(session, id).await?;
                 Ok(AudioItem {
                     id,
-            uri: format!("spotify:track:{}", id.to_base62()),
+                    uri: format!("spotify:track:{}", uri),
                     files: item.files,
                     name: item.name,
                     duration: item.duration,
@@ -94,16 +100,23 @@ impl AudioFiles for Track {
                     alternatives: Some(item.alternatives),
                 })
             }
+        }
+    }
 }
 
 #[async_trait]
 impl AudioFiles for Episode {
     async fn get_audio_item(session: &Session, id: SpotifyId) -> Result<AudioItem, MercuryError> {
+        match id.to_base62() {
+            Err(e) => {
+                warn!("Invalid Episode SpotifyId: {}", e);
+                Err(MercuryError)
+            }
+            Ok(uri) => {
                 let item = Self::get(session, id).await?;
-
                 Ok(AudioItem {
                     id,
-            uri: format!("spotify:episode:{}", id.to_base62()),
+                    uri: format!("spotify:episode:{}", uri),
                     files: item.files,
                     name: item.name,
                     duration: item.duration,
@@ -111,22 +124,46 @@ impl AudioFiles for Episode {
                     alternatives: None,
                 })
             }
+        }
+    }
 }
 
 #[async_trait]
 pub trait Metadata: Send + Sized + 'static {
     type Message: protobuf::Message;
 
-    fn request_url(id: SpotifyId) -> String;
+    fn request_url(id: SpotifyId) -> Result<String, FromUtf8Error>;
-    fn parse(msg: &Self::Message, session: &Session) -> Self;
+    fn parse(msg: &Self::Message, session: &Session) -> Result<Self, SpotifyIdError>;
 
     async fn get(session: &Session, id: SpotifyId) -> Result<Self, MercuryError> {
-        let uri = Self::request_url(id);
+        match Self::request_url(id) {
+            Err(e) => {
+                warn!("Invalid SpotifyId: {}", e);
+                Err(MercuryError)
+            }
+            Ok(uri) => {
                 let response = session.mercury().get(uri).await?;
-        let data = response.payload.first().expect("Empty payload");
+                match response.payload.first() {
-        let msg = Self::Message::parse_from_bytes(data).unwrap();
+                    None => {
-
+                        warn!("Empty payload");
-        Ok(Self::parse(&msg, session))
+                        Err(MercuryError)
+                    }
+                    Some(data) => match Self::Message::parse_from_bytes(data) {
+                        Err(e) => {
+                            warn!("Error parsing message from bytes: {}", e);
+                            Err(MercuryError)
+                        }
+                        Ok(msg) => match Self::parse(&msg, session) {
+                            Err(e) => {
+                                warn!("Error parsing message: {:?}", e);
+                                Err(MercuryError)
+                            }
+                            Ok(parsed_msg) => Ok(parsed_msg),
+                        },
+                    },
+                }
+            }
+        }
     }
 }
 
@@ -192,101 +229,125 @@ pub struct Artist {
 impl Metadata for Track {
     type Message = protocol::metadata::Track;
 
-    fn request_url(id: SpotifyId) -> String {
+    fn request_url(id: SpotifyId) -> Result<String, FromUtf8Error> {
-        format!("hm://metadata/3/track/{}", id.to_base16())
+        let id = id.to_base16()?;
+        Ok(format!("hm://metadata/3/track/{}", id))
     }
 
-    fn parse(msg: &Self::Message, session: &Session) -> Self {
+    fn parse(msg: &Self::Message, session: &Session) -> Result<Self, SpotifyIdError> {
         let country = session.country();
 
         let artists = msg
             .get_artist()
             .iter()
-            .filter(|artist| artist.has_gid())
+            .filter_map(|artist| {
-            .map(|artist| SpotifyId::from_raw(artist.get_gid()).unwrap())
+                if artist.has_gid() {
-            .collect::<Vec<_>>();
+                    SpotifyId::from_raw(artist.get_gid()).ok()
+                } else {
+                    None
+                }
+            })
+            .collect();
 
         let files = msg
             .get_file()
             .iter()
-            .filter(|file| file.has_file_id())
+            .filter_map(|file| {
-            .map(|file| {
+                if file.has_file_id() {
                     let mut dst = [0u8; 20];
                     dst.clone_from_slice(file.get_file_id());
-                (file.get_format(), FileId(dst))
+                    Some((file.get_format(), FileId(dst)))
+                } else {
+                    None
+                }
             })
             .collect();
 
-        Track {
+        Ok(Track {
-            id: SpotifyId::from_raw(msg.get_gid()).unwrap(),
+            id: SpotifyId::from_raw(msg.get_gid())?,
             name: msg.get_name().to_owned(),
             duration: msg.get_duration(),
-            album: SpotifyId::from_raw(msg.get_album().get_gid()).unwrap(),
+            album: SpotifyId::from_raw(msg.get_album().get_gid())?,
             artists,
             files,
             alternatives: msg
                 .get_alternative()
                 .iter()
-                .map(|alt| SpotifyId::from_raw(alt.get_gid()).unwrap())
+                .filter_map(|alt| SpotifyId::from_raw(alt.get_gid()).ok())
                 .collect(),
             available: parse_restrictions(msg.get_restriction(), &country, "premium"),
-        }
+        })
     }
 }
 
 impl Metadata for Album {
     type Message = protocol::metadata::Album;
 
-    fn request_url(id: SpotifyId) -> String {
+    fn request_url(id: SpotifyId) -> Result<String, FromUtf8Error> {
-        format!("hm://metadata/3/album/{}", id.to_base16())
+        let id = id.to_base16()?;
+        Ok(format!("hm://metadata/3/album/{}", id))
     }
 
-    fn parse(msg: &Self::Message, _: &Session) -> Self {
+    fn parse(msg: &Self::Message, _: &Session) -> Result<Self, SpotifyIdError> {
         let artists = msg
             .get_artist()
             .iter()
-            .filter(|artist| artist.has_gid())
+            .filter_map(|artist| {
-            .map(|artist| SpotifyId::from_raw(artist.get_gid()).unwrap())
+                if artist.has_gid() {
-            .collect::<Vec<_>>();
+                    SpotifyId::from_raw(artist.get_gid()).ok()
+                } else {
+                    None
+                }
+            })
+            .collect();
 
         let tracks = msg
             .get_disc()
             .iter()
             .flat_map(|disc| disc.get_track())
-            .filter(|track| track.has_gid())
+            .filter_map(|track| {
-            .map(|track| SpotifyId::from_raw(track.get_gid()).unwrap())
+                if track.has_gid() {
-            .collect::<Vec<_>>();
+                    SpotifyId::from_raw(track.get_gid()).ok()
+                } else {
+                    None
+                }
+            })
+            .collect();
 
         let covers = msg
             .get_cover_group()
             .get_image()
             .iter()
-            .filter(|image| image.has_file_id())
+            .filter_map(|image| {
-            .map(|image| {
+                if image.has_file_id() {
                     let mut dst = [0u8; 20];
                     dst.clone_from_slice(image.get_file_id());
-                FileId(dst)
+                    Some(FileId(dst))
+                } else {
+                    None
+                }
             })
-            .collect::<Vec<_>>();
+            .collect();
 
-        Album {
+        Ok(Album {
-            id: SpotifyId::from_raw(msg.get_gid()).unwrap(),
+            id: SpotifyId::from_raw(msg.get_gid())?,
             name: msg.get_name().to_owned(),
             artists,
             tracks,
             covers,
-        }
+        })
     }
 }
 
 impl Metadata for Playlist {
     type Message = protocol::playlist4changes::SelectedListContent;
 
-    fn request_url(id: SpotifyId) -> String {
+    fn request_url(id: SpotifyId) -> Result<String, FromUtf8Error> {
-        format!("hm://playlist/v2/playlist/{}", id.to_base62())
+        let id = id.to_base62()?;
+        Ok(format!("hm://playlist/v2/playlist/{}", id))
     }
 
-    fn parse(msg: &Self::Message, _: &Session) -> Self {
+    fn parse(msg: &Self::Message, _: &Session) -> Result<Self, SpotifyIdError> {
         let tracks = msg
             .get_contents()
             .get_items()
@@ -306,23 +367,24 @@ impl Metadata for Playlist {
             );
         }
 
-        Playlist {
+        Ok(Playlist {
             revision: msg.get_revision().to_vec(),
             name: msg.get_attributes().get_name().to_owned(),
             tracks,
             user: msg.get_owner_username().to_string(),
-        }
+        })
     }
 }
 
 impl Metadata for Artist {
     type Message = protocol::metadata::Artist;
 
-    fn request_url(id: SpotifyId) -> String {
+    fn request_url(id: SpotifyId) -> Result<String, FromUtf8Error> {
-        format!("hm://metadata/3/artist/{}", id.to_base16())
+        let id = id.to_base16()?;
+        Ok(format!("hm://metadata/3/artist/{}", id))
     }
 
-    fn parse(msg: &Self::Message, session: &Session) -> Self {
+    fn parse(msg: &Self::Message, session: &Session) -> Result<Self, SpotifyIdError> {
         let country = session.country();
 
         let top_tracks: Vec<SpotifyId> = match msg
@@ -333,17 +395,22 @@ impl Metadata for Artist {
             Some(tracks) => tracks
                 .get_track()
                 .iter()
-                .filter(|track| track.has_gid())
+                .filter_map(|track| {
-                .map(|track| SpotifyId::from_raw(track.get_gid()).unwrap())
+                    if track.has_gid() {
-                .collect::<Vec<_>>(),
+                        SpotifyId::from_raw(track.get_gid()).ok()
+                    } else {
+                        None
+                    }
+                })
+                .collect(),
             None => Vec::new(),
         };
 
-        Artist {
+        Ok(Artist {
-            id: SpotifyId::from_raw(msg.get_gid()).unwrap(),
+            id: SpotifyId::from_raw(msg.get_gid())?,
             name: msg.get_name().to_owned(),
             top_tracks,
-        }
+        })
     }
 }
 
@@ -351,11 +418,12 @@ impl Metadata for Artist {
 impl Metadata for Episode {
     type Message = protocol::metadata::Episode;
 
-    fn request_url(id: SpotifyId) -> String {
+    fn request_url(id: SpotifyId) -> Result<String, FromUtf8Error> {
-        format!("hm://metadata/3/episode/{}", id.to_base16())
+        let id = id.to_base16()?;
+        Ok(format!("hm://metadata/3/episode/{}", id))
     }
 
-    fn parse(msg: &Self::Message, session: &Session) -> Self {
+    fn parse(msg: &Self::Message, session: &Session) -> Result<Self, SpotifyIdError> {
         let country = session.country();
 
         let files = msg
@@ -379,9 +447,9 @@ impl Metadata for Episode {
                 dst.clone_from_slice(image.get_file_id());
                 FileId(dst)
             })
-            .collect::<Vec<_>>();
+            .collect();
 
-        Episode {
+        Ok(Episode {
             id: SpotifyId::from_raw(msg.get_gid()).unwrap(),
             name: msg.get_name().to_owned(),
             external_url: msg.get_external_url().to_owned(),
@@ -392,24 +460,30 @@ impl Metadata for Episode {
             files,
             available: parse_restrictions(msg.get_restriction(), &country, "premium"),
             explicit: msg.get_explicit().to_owned(),
-        }
+        })
     }
 }
 
 impl Metadata for Show {
     type Message = protocol::metadata::Show;
 
-    fn request_url(id: SpotifyId) -> String {
+    fn request_url(id: SpotifyId) -> Result<String, FromUtf8Error> {
-        format!("hm://metadata/3/show/{}", id.to_base16())
+        let id = id.to_base16()?;
+        Ok(format!("hm://metadata/3/show/{}", id))
     }
 
-    fn parse(msg: &Self::Message, _: &Session) -> Self {
+    fn parse(msg: &Self::Message, _: &Session) -> Result<Self, SpotifyIdError> {
         let episodes = msg
             .get_episode()
             .iter()
-            .filter(|episode| episode.has_gid())
+            .filter_map(|episode| {
-            .map(|episode| SpotifyId::from_raw(episode.get_gid()).unwrap())
+                if episode.has_gid() {
-            .collect::<Vec<_>>();
+                    SpotifyId::from_raw(episode.get_gid()).ok()
+                } else {
+                    None
+                }
+            })
+            .collect();
 
         let covers = msg
             .get_covers()
@@ -421,15 +495,15 @@ impl Metadata for Show {
                 dst.clone_from_slice(image.get_file_id());
                 FileId(dst)
             })
-            .collect::<Vec<_>>();
+            .collect();
 
-        Show {
+        Ok(Show {
             id: SpotifyId::from_raw(msg.get_gid()).unwrap(),
             name: msg.get_name().to_owned(),
             publisher: msg.get_publisher().to_owned(),
             episodes,
             covers,
-        }
+        })
     }
 }
 

playback/src/player.rs

@@ -740,7 +740,10 @@ impl PlayerTrackLoader {
         let audio = match self.find_available_alternative(audio).await {
             Some(audio) => audio,
             None => {
-                warn!("<{}> is not available", spotify_id.to_uri());
+                warn!(
+                    "<{}> is not available",
+                    spotify_id.to_uri().unwrap_or_default()
+                );
                 return None;
             }
         };
@@ -748,7 +751,7 @@ impl PlayerTrackLoader {
         if audio.duration < 0 {
             error!(
                 "Track duration for <{}> cannot be {}",
-                spotify_id.to_uri(),
+                spotify_id.to_uri().unwrap_or_default(),
                 audio.duration
             );
             return None;

src/player_event_handler.rs

@@ -5,6 +5,7 @@ use tokio::process::{Child as AsyncChild, Command as AsyncCommand};
 
 use std::collections::HashMap;
 use std::io;
+use std::io::{Error, ErrorKind};
 use std::process::{Command, ExitStatus};
 
 pub fn run_program_on_events(event: PlayerEvent, onevent: &str) -> Option<io::Result<AsyncChild>> {
@@ -13,45 +14,110 @@ pub fn run_program_on_events(event: PlayerEvent, onevent: &str) -> Option<io::Re
         PlayerEvent::Changed {
             old_track_id,
             new_track_id,
-        } => {
+        } => match old_track_id.to_base62() {
+            Err(e) => {
+                return Some(Err(Error::new(
+                    ErrorKind::InvalidData,
+                    format!(
+                        "PlayerEvent::Changed: Invalid old track id: {}",
+                        e.utf8_error()
+                    ),
+                )))
+            }
+            Ok(old_id) => match new_track_id.to_base62() {
+                Err(e) => {
+                    return Some(Err(Error::new(
+                        ErrorKind::InvalidData,
+                        format!(
+                            "PlayerEvent::Changed: Invalid new track id: {}",
+                            e.utf8_error()
+                        ),
+                    )))
+                }
+                Ok(new_id) => {
                     env_vars.insert("PLAYER_EVENT", "changed".to_string());
-            env_vars.insert("OLD_TRACK_ID", old_track_id.to_base62());
+                    env_vars.insert("OLD_TRACK_ID", old_id);
-            env_vars.insert("TRACK_ID", new_track_id.to_base62());
+                    env_vars.insert("TRACK_ID", new_id);
                 }
-        PlayerEvent::Started { track_id, .. } => {
+            },
+        },
+        PlayerEvent::Started { track_id, .. } => match track_id.to_base62() {
+            Err(e) => {
+                return Some(Err(Error::new(
+                    ErrorKind::InvalidData,
+                    format!("PlayerEvent::Started: Invalid track id: {}", e.utf8_error()),
+                )))
+            }
+            Ok(id) => {
                 env_vars.insert("PLAYER_EVENT", "started".to_string());
-            env_vars.insert("TRACK_ID", track_id.to_base62());
+                env_vars.insert("TRACK_ID", id);
             }
-        PlayerEvent::Stopped { track_id, .. } => {
+        },
+        PlayerEvent::Stopped { track_id, .. } => match track_id.to_base62() {
+            Err(e) => {
+                return Some(Err(Error::new(
+                    ErrorKind::InvalidData,
+                    format!("PlayerEvent::Stopped: Invalid track id: {}", e.utf8_error()),
+                )))
+            }
+            Ok(id) => {
                 env_vars.insert("PLAYER_EVENT", "stopped".to_string());
-            env_vars.insert("TRACK_ID", track_id.to_base62());
+                env_vars.insert("TRACK_ID", id);
             }
+        },
         PlayerEvent::Playing {
             track_id,
             duration_ms,
             position_ms,
             ..
-        } => {
+        } => match track_id.to_base62() {
+            Err(e) => {
+                return Some(Err(Error::new(
+                    ErrorKind::InvalidData,
+                    format!("PlayerEvent::Playing: Invalid track id: {}", e.utf8_error()),
+                )))
+            }
+            Ok(id) => {
                 env_vars.insert("PLAYER_EVENT", "playing".to_string());
-            env_vars.insert("TRACK_ID", track_id.to_base62());
+                env_vars.insert("TRACK_ID", id);
                 env_vars.insert("DURATION_MS", duration_ms.to_string());
                 env_vars.insert("POSITION_MS", position_ms.to_string());
             }
+        },
         PlayerEvent::Paused {
             track_id,
             duration_ms,
             position_ms,
             ..
-        } => {
+        } => match track_id.to_base62() {
+            Err(e) => {
+                return Some(Err(Error::new(
+                    ErrorKind::InvalidData,
+                    format!("PlayerEvent::Paused: Invalid track id: {}", e.utf8_error()),
+                )))
+            }
+            Ok(id) => {
                 env_vars.insert("PLAYER_EVENT", "paused".to_string());
-            env_vars.insert("TRACK_ID", track_id.to_base62());
+                env_vars.insert("TRACK_ID", id);
                 env_vars.insert("DURATION_MS", duration_ms.to_string());
                 env_vars.insert("POSITION_MS", position_ms.to_string());
             }
-        PlayerEvent::Preloading { track_id, .. } => {
+        },
-            env_vars.insert("PLAYER_EVENT", "preloading".to_string());
+        PlayerEvent::Preloading { track_id, .. } => match track_id.to_base62() {
-            env_vars.insert("TRACK_ID", track_id.to_base62());
+            Err(e) => {
+                return Some(Err(Error::new(
+                    ErrorKind::InvalidData,
+                    format!(
+                        "PlayerEvent::Preloading: Invalid track id: {}",
+                        e.utf8_error()
+                    ),
+                )))
             }
+            Ok(id) => {
+                env_vars.insert("PLAYER_EVENT", "preloading".to_string());
+                env_vars.insert("TRACK_ID", id);
+            }
+        },
         PlayerEvent::VolumeSet { volume } => {
             env_vars.insert("PLAYER_EVENT", "volume_set".to_string());
             env_vars.insert("VOLUME", volume.to_string());