Handled upload errors

vospace-ui-frontend/src/store.js

@@ -188,15 +188,23 @@ export default new Vuex.Store({
       for (let file of files) {
         names.push(file.name);
       }
-      client.prepareForUpload(state.path, names)
+      return client.prepareForUpload(state.path, names)
         .then(uploadUrls => {
           let uploads = [];
           for (let i = 0; i < files.length; i++) {
             uploads.push(client.uploadFile(uploadUrls[i], files[i]));
           }
-          Promise.all(uploads).then(() => {
+          Promise.all(uploads)
+            .then(() => {
               // Reload current node when all uploads completed
               dispatch('setPath', state.path);
+            })
+            .catch(error => {
+              let message = "Unable to upload file"
+              if (error.response && error.response.data) {
+                message += ": " + error.response.data;
+              }
+              main.showError(message);
             });
         });
     },