Refactor asyncio locking system for Python 3.7 support. Ref https://github.com/GNS3/gns3-gui/issues/2566 Ref https://github.com/GNS3/gns3-gui/issues/2568

gns3server/compute/base_node.py

@@ -29,7 +29,7 @@ import re
 
 from gns3server.utils.interfaces import interfaces
 from ..compute.port_manager import PortManager
-from ..utils.asyncio import wait_run_in_executor, locked_coroutine
+from ..utils.asyncio import wait_run_in_executor, locking
 from ..utils.asyncio.telnet_server import AsyncioTelnetServer
 from ..ubridge.hypervisor import Hypervisor
 from ..ubridge.ubridge_error import UbridgeError
@@ -516,7 +516,8 @@ class BaseNode:
         except UbridgeError as e:
             raise UbridgeError("Error while sending command '{}': {}: {}".format(command, e, self._ubridge_hypervisor.read_stdout()))
 
-    @locked_coroutine
+    @locking
+    @asyncio.coroutine
     def _start_ubridge(self):
         """
         Starts uBridge (handles connections to and from this node).

gns3server/compute/docker/__init__.py

@@ -25,7 +25,7 @@ import asyncio
 import logging
 import aiohttp
 from gns3server.utils import parse_version
-from gns3server.utils.asyncio import locked_coroutine
+from gns3server.utils.asyncio import locking
 from gns3server.compute.base_manager import BaseManager
 from gns3server.compute.docker.docker_vm import DockerVM
 from gns3server.compute.docker.docker_error import DockerError, DockerHttp304Error, DockerHttp404Error
@@ -182,7 +182,8 @@ class Docker(BaseManager):
                                                          autoping=True)
         return connection
 
-    @locked_coroutine
+    @locking
+    @asyncio.coroutine
     def pull_image(self, image, progress_callback=None):
         """
         Pull image from docker repository

gns3server/compute/iou/iou_vm.py

@@ -43,7 +43,7 @@ from .utils.iou_export import nvram_export
 from gns3server.ubridge.ubridge_error import UbridgeError
 from gns3server.utils.file_watcher import FileWatcher
 from gns3server.utils.asyncio.telnet_server import AsyncioTelnetServer
-from gns3server.utils.asyncio import locked_coroutine
+from gns3server.utils.asyncio import locking
 import gns3server.utils.asyncio
 import gns3server.utils.images
 
@@ -550,7 +550,8 @@ class IOUVM(BaseNode):
             # configure networking support
             yield from self._networking()
 
-    @locked_coroutine
+    @locking
+    @asyncio.coroutine
     def _networking(self):
         """
         Configures the IOL bridge in uBridge.

gns3server/compute/virtualbox/virtualbox_vm.py

@@ -33,7 +33,7 @@ import xml.etree.ElementTree as ET
 from gns3server.utils import parse_version
 from gns3server.utils.asyncio.telnet_server import AsyncioTelnetServer
 from gns3server.utils.asyncio.serial import asyncio_open_serial
-from gns3server.utils.asyncio import locked_coroutine
+from gns3server.utils.asyncio import locking
 from gns3server.compute.virtualbox.virtualbox_error import VirtualBoxError
 from gns3server.compute.nios.nio_udp import NIOUDP
 from gns3server.compute.adapters.ethernet_adapter import EthernetAdapter
@@ -296,7 +296,8 @@ class VirtualBoxVM(BaseNode):
         if (yield from self.check_hw_virtualization()):
             self._hw_virtualization = True
 
-    @locked_coroutine
+    @locking
+    @asyncio.coroutine
     def stop(self):
         """
         Stops this VirtualBox VM.

gns3server/compute/vmware/vmware_vm.py

@@ -26,7 +26,7 @@ import tempfile
 
 from gns3server.utils.asyncio.telnet_server import AsyncioTelnetServer
 from gns3server.utils.asyncio.serial import asyncio_open_serial
-from gns3server.utils.asyncio import locked_coroutine
+from gns3server.utils.asyncio import locking
 from collections import OrderedDict
 from .vmware_error import VMwareError
 from ..nios.nio_udp import NIOUDP
@@ -94,7 +94,8 @@ class VMwareVM(BaseNode):
 
         return self._vmnets
 
-    @locked_coroutine
+    @locking
+    @asyncio.coroutine
     def _control_vm(self, subcommand, *additional_args):
 
         args = [self._vmx_path]

gns3server/controller/compute.py

@@ -27,7 +27,7 @@ from operator import itemgetter
 
 from ..utils import parse_version
 from ..utils.images import list_images
-from ..utils.asyncio import locked_coroutine, asyncio_ensure_future
+from ..utils.asyncio import locking, asyncio_ensure_future
 from ..controller.controller_error import ControllerError
 from ..version import __version__, __version_info__
 
@@ -400,7 +400,8 @@ class Compute:
         except aiohttp.web.HTTPConflict:
             pass
 
-    @locked_coroutine
+    @locking
+    @asyncio.coroutine
     def connect(self):
         """
         Check if remote server is accessible

gns3server/controller/gns3vm/__init__.py

@@ -21,7 +21,7 @@ import asyncio
 import aiohttp
 import ipaddress
 
-from ...utils.asyncio import locked_coroutine, asyncio_ensure_future
+from ...utils.asyncio import locking, asyncio_ensure_future
 from .vmware_gns3_vm import VMwareGNS3VM
 from .virtualbox_gns3_vm import VirtualBoxGNS3VM
 from .remote_gns3_vm import RemoteGNS3VM
@@ -265,7 +265,8 @@ class GNS3VM:
             except GNS3VMError as e:
                 log.warn(str(e))
 
-    @locked_coroutine
+    @locking
+    @asyncio.coroutine
     def start(self):
         """
         Start the GNS3 VM
@@ -339,7 +340,8 @@ class GNS3VM:
         except aiohttp.web.HTTPConflict as e:
             log.warning("Could not check the VM is in the same subnet as the local server: {}".format(e.text))
 
-    @locked_coroutine
+    @locking
+    @asyncio.coroutine
     def _suspend(self):
         """
         Suspend the GNS3 VM
@@ -351,7 +353,8 @@ class GNS3VM:
             log.info("Suspend the GNS3 VM")
             yield from engine.suspend()
 
-    @locked_coroutine
+    @locking
+    @asyncio.coroutine
     def _stop(self):
         """
         Stop the GNS3 VM

gns3server/controller/project.py

@@ -36,7 +36,7 @@ from .udp_link import UDPLink
 from ..config import Config
 from ..utils.path import check_path_allowed, get_default_project_directory
 from ..utils.asyncio.pool import Pool
-from ..utils.asyncio import locked_coroutine
+from ..utils.asyncio import locking
 from ..utils.asyncio import wait_run_in_executor
 from ..utils.asyncio import asyncio_ensure_future
 from .export_project import export_project
@@ -525,7 +525,8 @@ class Project:
             self.dump()
         return node
 
-    @locked_coroutine
+    @locking
+    @asyncio.coroutine
     def __delete_node_links(self, node):
         """
         Delete all link connected to this node.
@@ -783,7 +784,8 @@ class Project:
     def _topology_file(self):
         return os.path.join(self.path, self._filename)
 
-    @locked_coroutine
+    @locking
+    @asyncio.coroutine
     def open(self):
         """
         Load topology elements

gns3server/ubridge/ubridge_hypervisor.py

@@ -20,7 +20,7 @@ import time
 import logging
 import asyncio
 
-from ..utils.asyncio import locked_coroutine
+from ..utils.asyncio import locking
 from .ubridge_error import UbridgeError
 
 log = logging.getLogger(__name__)
@@ -176,7 +176,8 @@ class UBridgeHypervisor:
 
         self._host = host
 
-    @locked_coroutine
+    @locking
+    @asyncio.coroutine
     def send(self, command):
         """
         Sends commands to this hypervisor.

gns3server/utils/asyncio/__init__.py

@@ -138,26 +138,28 @@ def wait_for_named_pipe_creation(pipe_path, timeout=60):
             return
     raise asyncio.TimeoutError()
 
+#FIXME: Use the following wrapper when we drop Python 3.4 and use the async def syntax
+# def locking(f):
+#
+#     @wraps(f)
+#     async def wrapper(oself, *args, **kwargs):
+#         lock_name = "__" + f.__name__ + "_lock"
+#         if not hasattr(oself, lock_name):
+#             setattr(oself, lock_name, asyncio.Lock())
+#         async with getattr(oself, lock_name):
+#             return await f(oself, *args, **kwargs)
+#     return wrapper
 
-def locked_coroutine(f):
-    """
-    Method decorator that replace asyncio.coroutine that warranty
-    that this specific method of this class instance will not we
-    executed twice at the same time
-    """
-    @asyncio.coroutine
-    def new_function(*args, **kwargs):
+def locking(f):
 
-        # In the instance of the class we will store
-        # a lock has an attribute.
-        lock_var_name = "__" + f.__name__ + "_lock"
-        if not hasattr(args[0], lock_var_name):
-            setattr(args[0], lock_var_name, asyncio.Lock())
-
-        with (yield from getattr(args[0], lock_var_name)):
-            return (yield from f(*args, **kwargs))
-
-    return new_function
+    @functools.wraps(f)
+    def wrapper(oself, *args, **kwargs):
+        lock_name = "__" + f.__name__ + "_lock"
+        if not hasattr(oself, lock_name):
+            setattr(oself, lock_name, asyncio.Lock())
+        with (yield from getattr(oself, lock_name)):
+            return (yield from f(oself, *args, **kwargs))
+    return wrapper
 
 #FIXME: conservative approach to supported versions, please remove it when we drop the support to Python < 3.4.4
 try: