rust: upload release artifacts in parallel

It takes several minutes to upload releases. And GitHub sorts the
artifacts by their filename, so upload order isn't important. Let's
upload in parallel so things finish faster.

Author: indygreg

src/github.rs

@@ -34,7 +34,7 @@ async fn fetch_artifact(client: &Octocrab, artifact: WorkflowListArtifact) -> Re
 async fn upload_release_artifact(
     client: &Octocrab,
     release: &Release,
-    filename: &str,
+    filename: String,
     data: Vec<u8>,
     dry_run: bool,
 ) -> Result<()> {
@@ -50,7 +50,7 @@ async fn upload_release_artifact(
         url.set_path(path);
     }
 
-    url.query_pairs_mut().clear().append_pair("name", filename);
+    url.query_pairs_mut().clear().append_pair("name", &filename);
 
     println!("uploading to {}", url);
 
@@ -364,6 +364,8 @@ pub async fn command_upload_release_distributions(args: &ArgMatches) -> Result<(
 
     let mut digests = BTreeMap::new();
 
+    let mut fs = vec![];
+
     for (source, dest) in wanted_filenames {
         if !filenames.contains(&source) {
             continue;
@@ -378,15 +380,26 @@ pub async fn command_upload_release_distributions(args: &ArgMatches) -> Result<(
 
         digests.insert(dest.clone(), digest.clone());
 
-        upload_release_artifact(&client, &release, &dest, file_data, dry_run).await?;
-        upload_release_artifact(
+        fs.push(upload_release_artifact(
             &client,
             &release,
-            &format!("{}.sha256", dest),
+            dest.clone(),
+            file_data,
+            dry_run,
+        ));
+        fs.push(upload_release_artifact(
+            &client,
+            &release,
+            format!("{}.sha256", dest),
             format!("{}\n", digest).into_bytes(),
             dry_run,
-        )
-        .await?;
+        ));
+    }
+
+    let mut buffered = futures::stream::iter(fs).buffer_unordered(6);
+
+    while let Some(res) = buffered.next().await {
+        res?;
     }
 
     let shasums = digests
@@ -400,7 +413,7 @@ pub async fn command_upload_release_distributions(args: &ArgMatches) -> Result<(
     upload_release_artifact(
         &client,
         &release,
-        "SHA256SUMS",
+        "SHA256SUMS".to_string(),
         shasums.into_bytes(),
         dry_run,
     )