[file view] added 'catch' for requests

* added 'getErrorMsg' to utils.js

frontend/src/components/file-view/file-view.js

@@ -3,6 +3,8 @@ import PropTypes from 'prop-types';
 import watermark from 'watermark-dom';
 import { seafileAPI } from '../../utils/seafile-api';
 import { siteName } from '../../utils/constants';
+import { Utils } from '../../utils/utils';
+import toaster from '../toast';
 import FileInfo from './file-info';
 import FileToolbar from './file-toolbar';
 import CommentPanel from './comment-panel';
@@ -45,12 +47,18 @@ class FileView extends React.Component {
         this.setState({
           isStarred: false
         });
+      }).catch((error) => {
+        const errorMsg = Utils.getErrorMsg(error);
+        toaster.danger(errorMsg);
       });
     } else {
       seafileAPI.starItem(repoID, filePath).then((res) => {
         this.setState({
           isStarred: true
         });
+      }).catch((error) => {
+        const errorMsg = Utils.getErrorMsg(error);
+        toaster.danger(errorMsg);
       });
     }
   }
@@ -62,6 +70,9 @@ class FileView extends React.Component {
           isLocked: false, 
           lockedByMe: false 
         });
+      }).catch((error) => {
+        const errorMsg = Utils.getErrorMsg(error);
+        toaster.danger(errorMsg);
       });
     } else {
       seafileAPI.lockfile(repoID, filePath).then((res) => {
@@ -69,6 +80,9 @@ class FileView extends React.Component {
           isLocked: true,
           lockedByMe: true
         });
+      }).catch((error) => {
+        const errorMsg = Utils.getErrorMsg(error);
+        toaster.danger(errorMsg);
       });
     }    
   }

frontend/src/utils/utils.js

@@ -734,6 +734,23 @@ export const Utils = {
     return items;
   },
 
+  /*
+   * only used in the 'catch' part of a seafileAPI request
+   */
+  getErrorMsg: function(error) {
+    let errorMsg = '';
+    if (error.response) {
+      if (error.response.data && error.response.data['error_msg']) {
+        errorMsg = error.response.data['error_msg'];
+      } else {
+        errorMsg = gettext('Error');
+      }
+    } else {
+      errorMsg = gettext('Please check the network.');
+    }
+    return errorMsg;
+  },
+
   changeMarkdownNodes: function(nodes, fn) {
     nodes.map((item) => {
       fn(item);