Docker capture and refactor common capture code

Fix https://github.com/GNS3/gns3-gui/issues/891

tests/modules/vmware/test_vmware_vm.py

@@ -49,3 +49,25 @@ def test_json(vm, tmpdir, project):
     project._path = str(tmpdir)
     vm._linked_clone = True
     assert vm.__json__()["vm_directory"] is not None
+
+
+def test_start_capture(vm, tmpdir, manager, free_console_port, loop):
+
+    output_file = str(tmpdir / "test.pcap")
+    nio = manager.create_nio(0, {"type": "nio_udp", "lport": free_console_port, "rport": free_console_port, "rhost": "127.0.0.1"})
+    vm.adapters = 1
+    loop.run_until_complete(asyncio.async(vm.adapter_add_nio_binding(0, nio)))
+    loop.run_until_complete(asyncio.async(vm.start_capture(0, output_file)))
+    assert vm._ethernet_adapters[0].get_nio(0).capturing
+
+
+def test_stop_capture(vm, tmpdir, manager, free_console_port, loop):
+
+    output_file = str(tmpdir / "test.pcap")
+    nio = manager.create_nio(0, {"type": "nio_udp", "lport": free_console_port, "rport": free_console_port, "rhost": "127.0.0.1"})
+    vm.adapters = 1
+    loop.run_until_complete(asyncio.async(vm.adapter_add_nio_binding(0, nio)))
+    loop.run_until_complete(vm.start_capture(0, output_file))
+    assert vm._ethernet_adapters[0].get_nio(0).capturing
+    loop.run_until_complete(asyncio.async(vm.stop_capture(0)))
+    assert vm._ethernet_adapters[0].get_nio(0).capturing is False