Set custom user agent on client

Signed-off-by: Ben Firshman <ben@firshman.co.uk>

docker/client.py

@@ -50,7 +50,8 @@ class Client(
         api.VolumeApiMixin,
         api.NetworkApiMixin):
     def __init__(self, base_url=None, version=None,
-                 timeout=constants.DEFAULT_TIMEOUT_SECONDS, tls=False):
+                 timeout=constants.DEFAULT_TIMEOUT_SECONDS, tls=False,
+                 user_agent=constants.DEFAULT_USER_AGENT):
         super(Client, self).__init__()
 
         if tls and not base_url:
@@ -60,6 +61,7 @@ class Client(
 
         self.base_url = base_url
         self.timeout = timeout
+        self.headers['User-Agent'] = user_agent
 
         self._auth_configs = auth.load_config()
 

docker/constants.py

 import sys
+from .version import version
 
 DEFAULT_DOCKER_API_VERSION = '1.22'
 DEFAULT_TIMEOUT_SECONDS = 60
@@ -12,3 +13,5 @@ INSECURE_REGISTRY_DEPRECATION_WARNING = \
     'is deprecated and non-functional. Please remove it.'
 
 IS_WINDOWS_PLATFORM = (sys.platform == 'win32')
+
+DEFAULT_USER_AGENT = "docker-py/{0}".format(version)

docs/api.md

@@ -16,6 +16,7 @@ is hosted.
   to use the API version provided by the server.
 * timeout (int): The HTTP request timeout, in seconds.
 * tls (bool or [TLSConfig](tls.md#TLSConfig)): Equivalent CLI options: `docker --tls ...`
+* user_agent (str): Set a custom user agent for requests to the server.
 
 ****
 

tests/unit/api_test.py

@@ -420,3 +420,33 @@ class StreamTest(base.Cleanup, base.BaseTestCase):
 
             self.assertEqual(list(stream), [
                 str(i).encode() for i in range(50)])
+
+
+class UserAgentTest(base.BaseTestCase):
+    def setUp(self):
+        self.patcher = mock.patch.object(
+            docker.Client,
+            'send',
+            return_value=fake_resp("GET", "%s/version" % fake_api.prefix)
+        )
+        self.mock_send = self.patcher.start()
+
+    def tearDown(self):
+        self.patcher.stop()
+
+    def test_default_user_agent(self):
+        client = docker.Client()
+        client.version()
+
+        self.assertEqual(self.mock_send.call_count, 1)
+        headers = self.mock_send.call_args[0][0].headers
+        expected = 'docker-py/%s' % docker.__version__
+        self.assertEqual(headers['User-Agent'], expected)
+
+    def test_custom_user_agent(self):
+        client = docker.Client(user_agent='foo/bar')
+        client.version()
+
+        self.assertEqual(self.mock_send.call_count, 1)
+        headers = self.mock_send.call_args[0][0].headers
+        self.assertEqual(headers['User-Agent'], 'foo/bar')