fix missing assets when uploading to S3 (#2535)

Author: mcasimir

packages/hadron-build/commands/upload.js

@@ -43,16 +43,7 @@ async function maybePublishGitHubRelease(target) {
   // already published releases.
   await repo.updateDraftRelease(release);
 
-  const assets = target.assets.filter(function(asset) {
-    // eslint-disable-next-line no-sync
-    var exists = fs.existsSync(asset.path);
-    if (!exists) {
-      cli.warn(`Excluding ${asset.path} from upload because it does not exist.`);
-    }
-    return exists;
-  });
-
-  const uploads = assets.map(
+  const uploads = target.assets.map(
     async function(asset) {
       cli.info(`${asset.name}: upload to Github release ${releaseTag} started (path: ${asset.path}).`);
       await repo.uploadReleaseAsset(releaseTag, {
@@ -92,6 +83,15 @@ exports.handler = function(argv) {
     return;
   }
 
+  target.assets = target.assets.filter(function(asset) {
+    // eslint-disable-next-line no-sync
+    var exists = fs.existsSync(asset.path);
+    if (!exists) {
+      cli.warn(`Excluding ${asset.path} from upload because it does not exist.`);
+    }
+    return exists;
+  });
+
   maybePublishGitHubRelease(target)
     .then(() => downloadCenter.maybeUpload(target))
     .catch(abortIfError);