Errors and types

src/tui/app/machine/fetch_state.rs

@@ -8,11 +8,10 @@ use musichoard::collection::{artist::Artist, musicbrainz::IMusicBrainzRef};
 use crate::tui::{
     app::{
         machine::{match_state::MatchState, App, AppInner, AppMachine},
-        AppPublicState, AppState, IAppEventFetch, IAppInteractFetch, MatchStateInfo,
+        AppPublicState, AppState, IAppEventFetch, IAppInteractFetch,
     },
-    lib::{
-        external::musicbrainz::daemon::{MbParams, ResultSender},
-        interface::musicbrainz::api::Error as MbError,
+    lib::external::musicbrainz::daemon::{
+        Error as DaemonError, IMbJobSender, MbApiResult, MbParams, ResultSender,
     },
 };
 
@@ -20,16 +19,13 @@ pub struct FetchState {
     fetch_rx: FetchReceiver,
 }
 
+pub type FetchReceiver = mpsc::Receiver<MbApiResult>;
 impl FetchState {
     pub fn new(fetch_rx: FetchReceiver) -> Self {
         FetchState { fetch_rx }
     }
 }
 
-pub type FetchError = MbError;
-pub type FetchResult = Result<MatchStateInfo, FetchError>;
-pub type FetchReceiver = mpsc::Receiver<FetchResult>;
-
 impl AppMachine<FetchState> {
     fn fetch_state(inner: AppInner, state: FetchState) -> Self {
         AppMachine::new(inner, state)
@@ -44,8 +40,10 @@ impl AppMachine<FetchState> {
             }
         };
 
-        let (fetch_tx, fetch_rx) = mpsc::channel::<FetchResult>();
-        Self::submit_fetch_job(&inner, artist, fetch_tx);
+        let (fetch_tx, fetch_rx) = mpsc::channel::<MbApiResult>();
+        if let Err(err) = Self::submit_fetch_job(&inner.musicbrainz, fetch_tx, artist) {
+            return AppMachine::error_state(inner, err.to_string()).into();
+        }
 
         let fetch = FetchState::new(fetch_rx);
         AppMachine::app_fetch(inner, fetch, true)
@@ -79,19 +77,22 @@ impl AppMachine<FetchState> {
         }
     }
 
-    fn submit_fetch_job(inner: &AppInner, artist: &Artist, tx: ResultSender) {
-        let queue = match artist.meta.musicbrainz {
+    fn submit_fetch_job(
+        musicbrainz: &Box<dyn IMbJobSender>,
+        result_sender: ResultSender,
+        artist: &Artist,
+    ) -> Result<(), DaemonError> {
+        let requests = match artist.meta.musicbrainz {
             Some(ref arid) => {
                 let arid = arid.mbid();
-                artist
-                    .albums
-                    .iter()
+                let albums = artist.albums.iter();
+                albums
                     .map(|album| MbParams::search_release_group(arid.clone(), album.meta.clone()))
                     .collect()
             }
             None => VecDeque::from([MbParams::search_artist(artist.meta.clone())]),
         };
-        inner.musicbrainz.submit_background_job(tx, queue);
+        musicbrainz.submit_background_job(result_sender, requests)
     }
 }
 

src/tui/lib/external/musicbrainz/daemon/mod.rs

@@ -1,4 +1,4 @@
-use std::{collections::VecDeque, sync::mpsc, thread, time};
+use std::{collections::VecDeque, fmt, sync::mpsc, thread, time};
 
 use musichoard::collection::{album::AlbumMeta, artist::ArtistMeta, musicbrainz::Mbid};
 
@@ -13,6 +13,15 @@ pub enum Error {
     JobChannelDisconnected,
 }
 
+impl fmt::Display for Error {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match self {
+            Error::EventChannelDisconnected => write!(f, "the event channel is disconnected"),
+            Error::JobChannelDisconnected => write!(f, "the job channel is disconnected"),
+        }
+    }
+}
+
 pub struct MusicBrainzDaemon {
     musicbrainz: Box<dyn IMusicBrainz>,
     job_receiver: mpsc::Receiver<Job>,
@@ -46,7 +55,8 @@ enum JobPriority {
     Background,
 }
 
-pub type ResultSender = mpsc::Sender<Result<MatchStateInfo, ApiError>>;
+pub type MbApiResult = Result<MatchStateInfo, ApiError>;
+pub type ResultSender = mpsc::Sender<MbApiResult>;
 struct JobInstance {
     result_sender: ResultSender,
     requests: VecDeque<MbParams>,