Added preferred Docker API version. Fixes #2136

gns3server/compute/docker/__init__.py

@@ -36,6 +36,7 @@ log = logging.getLogger(__name__)
 # Be carefull to keep it consistent
 DOCKER_MINIMUM_API_VERSION = "1.25"
 DOCKER_MINIMUM_VERSION = "1.13"
+DOCKER_PREFERRED_API_VERSION = "1.30"
 
 
 class Docker(BaseManager):
@@ -50,6 +51,7 @@ class Docker(BaseManager):
         self.ubridge_lock = asyncio.Lock()
         self._connector = None
         self._session = None
+        self._api_version = DOCKER_MINIMUM_API_VERSION
 
     @asyncio.coroutine
     def _check_connection(self):
@@ -61,8 +63,17 @@ class Docker(BaseManager):
             except (aiohttp.errors.ClientOSError, FileNotFoundError):
                 self._connected = False
                 raise DockerError("Can't connect to docker daemon")
-            if parse_version(version["ApiVersion"]) < parse_version(DOCKER_MINIMUM_API_VERSION):
+
-                raise DockerError("Docker version is {}. GNS3 requires a minimum version of {}".format(version["Version"], DOCKER_MINIMUM_VERSION))
+            docker_version = parse_version(version['ApiVersion'])
+
+            if docker_version < parse_version(DOCKER_MINIMUM_API_VERSION):
+                raise DockerError(
+                    "Docker version is {}. GNS3 requires a minimum version of {}".format(
+                        version["Version"], DOCKER_MINIMUM_VERSION))
+
+            preferred_api_version = parse_version(DOCKER_PREFERRED_API_VERSION)
+            if docker_version >= preferred_api_version:
+                self._api_version = DOCKER_PREFERRED_API_VERSION
 
     def connector(self):
         if self._connector is None or self._connector.closed:
@@ -165,7 +176,7 @@ class Docker(BaseManager):
         :returns: Websocket
         """
 
-        url = "http://docker/v" + DOCKER_MINIMUM_API_VERSION + "/" + path
+        url = "http://docker/v" + self._api_version + "/" + path
         connection = yield from aiohttp.ws_connect(url,
                                                    connector=self.connector(),
                                                    origin="http://docker",

tests/compute/docker/test_docker.py

@@ -17,10 +17,10 @@
 
 import pytest
 import asyncio
-from unittest.mock import MagicMock
+from unittest.mock import MagicMock, patch
 
 from tests.utils import asyncio_patch, AsyncioMagicMock
-from gns3server.compute.docker import Docker
+from gns3server.compute.docker import Docker, DOCKER_PREFERRED_API_VERSION, DOCKER_MINIMUM_API_VERSION
 from gns3server.compute.docker.docker_error import DockerError, DockerHttp404Error
 
 
@@ -162,3 +162,40 @@ def test_pull_image(loop):
         with asyncio_patch("gns3server.compute.docker.Docker.http_query", return_value=mock_query) as mock:
             images = loop.run_until_complete(asyncio.async(Docker.instance().pull_image("ubuntu")))
             mock.assert_called_with("POST", "images/create", params={"fromImage": "ubuntu"}, timeout=None)
+
+
+def test_docker_check_connection_docker_minimum_version(vm, loop):
+    response = {
+        'ApiVersion': '1.01',
+        'Version': '1.12'
+    }
+
+    with patch("gns3server.compute.docker.Docker.connector"), \
+        asyncio_patch("gns3server.compute.docker.Docker.query", return_value=response):
+        vm._connected = False
+        with pytest.raises(DockerError):
+            loop.run_until_complete(asyncio.async(vm._check_connection()))
+
+
+def test_docker_check_connection_docker_preferred_version_against_newer(vm, loop):
+    response = {
+        'ApiVersion': '1.31'
+    }
+
+    with patch("gns3server.compute.docker.Docker.connector"), \
+        asyncio_patch("gns3server.compute.docker.Docker.query", return_value=response):
+        vm._connected = False
+        loop.run_until_complete(asyncio.async(vm._check_connection()))
+        assert vm._api_version == DOCKER_PREFERRED_API_VERSION
+
+
+def test_docker_check_connection_docker_preferred_version_against_older(vm, loop):
+    response = {
+        'ApiVersion': '1.27',
+    }
+
+    with patch("gns3server.compute.docker.Docker.connector"), \
+        asyncio_patch("gns3server.compute.docker.Docker.query", return_value=response):
+        vm._connected = False
+        loop.run_until_complete(asyncio.async(vm._check_connection()))
+        assert vm._api_version == DOCKER_MINIMUM_API_VERSION