fix(bat-api): 完成 issue #19 同机 live 联调

infrastructure/src/downloader.rs

@@ -24,6 +24,10 @@ pub trait DownloaderBackend<T>: Send + Sync {
     fn download(&self, task: T) -> Result<Self::Output, Self::Error>;
 }
 
+/// Results returned by a scheduler for a task type and backend.
+pub type DownloadResults<T, B> =
+    Vec<Result<<B as DownloaderBackend<T>>::Output, <B as DownloaderBackend<T>>::Error>>;
+
 /// A bounded worker scheduler.
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub struct DownloadScheduler {
@@ -54,7 +58,7 @@ impl DownloadScheduler {
     /// order. A failed task does not cause additional tasks to be scheduled
     /// after it, because already-started bounded work must be joined cleanly;
     /// callers decide whether a failed result invalidates the whole release.
-    pub fn execute<T, B>(self, backend: &B, tasks: Vec<T>) -> Vec<Result<B::Output, B::Error>>
+    pub fn execute<T, B>(self, backend: &B, tasks: Vec<T>) -> DownloadResults<T, B>
     where
         T: Send + 'static,
         B: DownloaderBackend<T>,
@@ -78,7 +82,7 @@ impl DownloadScheduler {
         backend: &B,
         tasks: Vec<T>,
         mut observer: F,
-    ) -> Result<Vec<Result<B::Output, B::Error>>, E>
+    ) -> Result<DownloadResults<T, B>, E>
     where
         T: Send + 'static,
         B: DownloaderBackend<T>,