Merge pull request #5396 from ivanov/fix-5363

prevent saving of partially loaded notebooks

IPython/html/static/notebook/js/notebook.js

@@ -58,6 +58,9 b' var IPython = (function (IPython) {'
         this.style();
         this.create_elements();
         this.bind_events();
+        this.save_notebook = function() { // don't allow save until notebook_loaded
+            this.save_notebook_error(null, null, "Load failed, save is disabled");
+        };
     };
 
     /**
@@ -1723,7 +1726,8 b' var IPython = (function (IPython) {'
     };
     
     /**
-     * Save this notebook on the server.
+     * Save this notebook on the server. This becomes a notebook instance's
+     * .save_notebook method *after* the entire notebook has been loaded.
      * 
      * @method save_notebook
      */
@@ -2100,7 +2104,9 b' var IPython = (function (IPython) {'
             IPython.CellToolbar.global_show();
             IPython.CellToolbar.activate_preset(this.metadata.celltoolbar);
         }
-        
+
+        // now that we're fully loaded, it is safe to restore save functionality
+        delete(this.save_notebook);
         $([IPython.events]).trigger('notebook_loaded.Notebook');
     };
 

IPython/html/static/notebook/js/notificationarea.js

@@ -188,8 +188,8 b' var IPython = (function (IPython) {'
         $([IPython.events]).on('notebook_saved.Notebook', function () {
             nnw.set_message("Notebook saved",2000);
         });
-        $([IPython.events]).on('notebook_save_failed.Notebook', function () {
-            nnw.set_message("Notebook save failed");
+        $([IPython.events]).on('notebook_save_failed.Notebook', function (evt, xhr, status, data) {
+            nnw.set_message(data || "Notebook save failed");
         });
         
         // Checkpoint events