files: add pre-commit checks on file operations to prevent loosing content while editing when repositories change.

- fixes  #5607

rhodecode/apps/repository/__init__.py

@@ -156,6 +156,10 b' def includeme(config):'
         pattern='/{repo_name:.*?[^/]}/authors/{commit_id}/{f_path:.*}', repo_route=True)
 
     config.add_route(
+        name='repo_files_check_head',
+        pattern='/{repo_name:.*?[^/]}/check_head/{commit_id}/{f_path:.*}',
+        repo_route=True)
+    config.add_route(
         name='repo_files_remove_file',
         pattern='/{repo_name:.*?[^/]}/remove_file/{commit_id}/{f_path:.*}',
         repo_route=True)

rhodecode/apps/repository/views/repo_files.py

@@ -1114,6 +1114,42 b' class RepoFilesView(RepoAppView):'
     @LoginRequired()
     @HasRepoPermissionAnyDecorator('repository.write', 'repository.admin')
     @view_config(
+        route_name='repo_files_check_head', request_method='POST',
+        renderer='json_ext', xhr=True)
+    def repo_files_check_head(self):
+        self.load_default_context()
+
+        commit_id, f_path = self._get_commit_and_path()
+        _branch_name, _sha_commit_id, is_head = \
+            self._is_valid_head(commit_id, self.rhodecode_vcs_repo)
+
+        new_path = self.request.POST.get('path')
+        operation = self.request.POST.get('operation')
+        path_exist = ''
+
+        if new_path and operation in ['create', 'upload']:
+            new_f_path = os.path.join(f_path.lstrip('/'), new_path)
+            try:
+                commit_obj = self.rhodecode_vcs_repo.get_commit(commit_id)
+                # NOTE(dan): construct whole path without leading /
+                file_node = commit_obj.get_node(new_f_path)
+                if file_node is not None:
+                    path_exist = new_f_path
+            except EmptyRepositoryError:
+                pass
+            except Exception:
+                pass
+
+        return {
+            'branch': _branch_name,
+            'sha': _sha_commit_id,
+            'is_head': is_head,
+            'path_exists': path_exist
+        }
+
+    @LoginRequired()
+    @HasRepoPermissionAnyDecorator('repository.write', 'repository.admin')
+    @view_config(
         route_name='repo_files_remove_file', request_method='GET',
         renderer='rhodecode:templates/files/files_delete.mako')
     def repo_files_remove_file(self):

rhodecode/public/css/main.less

@@ -2532,6 +2532,10 b' h3.files_location{'
     white-space: nowrap;
   }
 
+  .upload-form {
+    margin-top: 46px;
+  }
+
   .location-path {
     width: -moz-available; /* WebKit-based browsers will ignore this. */
     width: -webkit-fill-available; /* Mozilla-based browsers will ignore this. */

rhodecode/public/js/rhodecode/routes.js

@@ -204,6 +204,7 b' function registerRCRoutes() {'
     pyroutes.register('repo_file_download:legacy', '/%(repo_name)s/rawfile/%(commit_id)s/%(f_path)s', ['repo_name', 'commit_id', 'f_path']);
     pyroutes.register('repo_file_history', '/%(repo_name)s/history/%(commit_id)s/%(f_path)s', ['repo_name', 'commit_id', 'f_path']);
     pyroutes.register('repo_file_authors', '/%(repo_name)s/authors/%(commit_id)s/%(f_path)s', ['repo_name', 'commit_id', 'f_path']);
+    pyroutes.register('repo_files_check_head', '/%(repo_name)s/check_head/%(commit_id)s/%(f_path)s', ['repo_name', 'commit_id', 'f_path']);
     pyroutes.register('repo_files_remove_file', '/%(repo_name)s/remove_file/%(commit_id)s/%(f_path)s', ['repo_name', 'commit_id', 'f_path']);
     pyroutes.register('repo_files_delete_file', '/%(repo_name)s/delete_file/%(commit_id)s/%(f_path)s', ['repo_name', 'commit_id', 'f_path']);
     pyroutes.register('repo_files_edit_file', '/%(repo_name)s/edit_file/%(commit_id)s/%(f_path)s', ['repo_name', 'commit_id', 'f_path']);

rhodecode/public/js/src/rhodecode/files.js

@@ -521,3 +521,80 b' var showAuthors = function(elem, annotat'
     return FileEditor;
 });
 
+
+var checkFileHead = function($editForm, commit_id, f_path, operation) {
+    function getFormData($form){
+        var unindexed_array = $form.serializeArray();
+        var indexed_array = {};
+
+        $.map(unindexed_array, function(n, i){
+            indexed_array[n['name']] = n['value'];
+        });
+
+        return indexed_array;
+    }
+
+    $editForm.on('submit', function (e) {
+
+        var validHead = $editForm.find('#commit_btn').data('validHead');
+        if (validHead === true){
+            return true
+        }
+
+        // no marker, we do "checks"
+        e.preventDefault();
+        var formData = getFormData($editForm);
+        var new_path = formData['filename'];
+
+        var success = function(data) {
+
+            if (data['is_head'] === true && data['path_exists'] === "") {
+
+                $editForm.find('#commit_btn').data('validHead', true);
+                $editForm.find('#commit_btn').val('Committing...');
+                $editForm.submit();
+
+            } else {
+                var message = '';
+                var urlTmpl = '<a target="_blank" href="{0}">here</a>';
+                $editForm.find('#commit_btn').val('Commit aborted');
+
+                if (operation === 'edit') {
+                    var new_url = urlTmpl.format(pyroutes.url('repo_files_edit_file', {"repo_name": templateContext.repo_name, "commit_id": data['branch'], "f_path": f_path}));
+                    message = _gettext('File `{0}` has a newer version available, or has been removed. Click {1} to see the latest version.'.format(f_path, new_url));
+                } else if (operation === 'delete') {
+                    var new_url = urlTmpl.format(pyroutes.url('repo_files_remove_file', {"repo_name": templateContext.repo_name, "commit_id": data['branch'], "f_path": f_path}));
+                    message = _gettext('File `{0}` has a newer version available, or has been removed. Click {1} to see the latest version.'.format(f_path, new_url));
+                } else if (operation === 'create') {
+                    if (data['path_exists'] !== "") {
+                        message = _gettext('There is an existing path `{0}` at this commit.'.format(data['path_exists']));
+                    } else {
+                        var new_url = urlTmpl.format(pyroutes.url('repo_files_add_file', {"repo_name": templateContext.repo_name, "commit_id": data['branch'], "f_path": f_path, "filename": new_path}));
+                        message = _gettext('There is a later version of file tree available. Click {0} to create a file at the latest tree.'.format(new_url));
+                    }
+                }
+
+                var payload = {
+                    message: {
+                        message: message,
+                        level: 'warning',
+                        force: true
+                    }
+                };
+                $.Topic('/notifications').publish(payload);
+            }
+        };
+
+        // lock button
+        $editForm.find('#commit_btn').attr('disabled', 'disabled');
+        $editForm.find('#commit_btn').val('Checking commit...');
+
+        var postData = {'csrf_token': CSRF_TOKEN, 'path': new_path, 'operation': operation};
+        ajaxPOST(pyroutes.url('repo_files_check_head',
+                {'repo_name': templateContext.repo_name, 'commit_id': commit_id, 'f_path': f_path}),
+                postData, success);
+
+        return false
+
+    });
+};

rhodecode/templates/files/files_add.mako

@@ -41,7 +41,7 b''
                 </div>
             </li>
             <li class="location-path">
-                <input  class="file-name-input input-small" type="text" value="" name="filename" id="filename" placeholder="${_('Filename e.g example.py, or docs/readme.md')}">
+                <input  class="file-name-input input-small" type="text" value="${request.GET.get('filename')}" name="filename" id="filename" placeholder="${_('Filename e.g example.py, or docs/readme.md')}">
             </li>
             </ul>
         </div>
@@ -50,7 +50,6 b''
 
     <div class="table">
         <div>
-
             <div id="codeblock" class="codeblock">
                 <div class="editor-items">
                     <div class="editor-action active show-editor pull-left" onclick="fileEditor.showEditor(); return false">
@@ -108,6 +107,10 b''
 
         $('#filename').focus();
 
+        var commit_id =  "${c.commit.raw_id}";
+        var f_path = "${c.f_path}";
+
+        checkFileHead($('#eform'), commit_id, f_path, 'create')
     });
 
 </script>

rhodecode/templates/files/files_delete.mako

@@ -69,7 +69,7 b''
             </div>
         </div>
         <div class="pull-left">
-            ${h.submit('commit',_('Commit changes'),class_="btn btn-small btn-danger-action")}
+            ${h.submit('commit_btn',_('Commit changes'),class_="btn btn-small btn-danger-action")}
         </div>
     </div>
     ${h.end_form()}
@@ -82,6 +82,10 b''
 
         fileEditor = new FileEditor('#editor');
 
+        var commit_id =  "${c.commit.raw_id}";
+        var f_path = "${c.f_path}";
+
+        checkFileHead($('#eform'), commit_id, f_path, 'delete');
     });
 
 </script>

rhodecode/templates/files/files_edit.mako

@@ -117,6 +117,11 b''
     // on entering the new filename set mode, from given extension
     setCodeMirrorModeFromInput(modes_select, filename_selector, fileEditor.cm, null);
 
+    var commit_id =  "${c.commit.raw_id}";
+    var f_path = "${c.f_path}";
+
+    checkFileHead($('#eform'), commit_id, f_path, 'edit')
+
 });
 
 

rhodecode/templates/files/files_upload.mako

@@ -106,7 +106,7 b''
 
     <div class="file-upload-transaction-wrapper" style="display: none">
     <div class="file-upload-transaction">
-        <h3>${_('Commiting...')}</h3>
+        <h3>${_('Committing...')}</h3>
         <p>${_('Please wait while the files are being uploaded')}</p>
         <p class="error" style="display: none">