Catch error when no space left on disk during export

Fix #801

gns3server/handlers/api/controller/project_handler.py

@@ -286,22 +286,26 @@ class ProjectHandler:
         controller = Controller.instance()
         project = yield from controller.get_loaded_project(request.match_info["project_id"])
 
-        with tempfile.TemporaryDirectory() as tmp_dir:
-            datas = yield from export_project(project, tmp_dir, include_images=bool(request.get("include_images", "0")))
-            # We need to do that now because export could failed and raise an HTTP error
-            # that why response start need to be the later possible
-            response.content_type = 'application/gns3project'
-            response.headers['CONTENT-DISPOSITION'] = 'attachment; filename="{}.gns3project"'.format(project.name)
-            response.enable_chunked_encoding()
-            # Very important: do not send a content length otherwise QT closes the connection (curl can consume the feed)
-            response.content_length = None
-            response.start(request)
-
-            for data in datas:
-                response.write(data)
-                yield from response.drain()
+        try:
+            with tempfile.TemporaryDirectory() as tmp_dir:
+                datas = yield from export_project(project, tmp_dir, include_images=bool(request.get("include_images", "0")))
+                # We need to do that now because export could failed and raise an HTTP error
+                # that why response start need to be the later possible
+                response.content_type = 'application/gns3project'
+                response.headers['CONTENT-DISPOSITION'] = 'attachment; filename="{}.gns3project"'.format(project.name)
+                response.enable_chunked_encoding()
+                # Very important: do not send a content length otherwise QT closes the connection (curl can consume the feed)
+                response.content_length = None
+                response.start(request)
 
-            yield from response.write_eof()
+                for data in datas:
+                    response.write(data)
+                    yield from response.drain()
+
+                yield from response.write_eof()
+        # Will be raise if you have no space left or permission issue on your temporary directory
+        except OSError as e:
+            raise aiohttp.web.HTTPNotFound(text="Can't export project: {}".format(str(e)))
 
     @Route.post(
         r"/projects/{project_id}/import",