Rework Unix connection code so that 'chunked' transfers work

This allows streaming a system to the 'import' command, rather than
having to read the whole thing into memory before sending it.

Previously both the UnixAdapter and the docker.Client objects would
track the 'base URL' of the Docker daemon (socket path in the case of
local Unix-domain socket connections). The Client object would construct
URLs which contained the path to the socket with the path of the Docker
API call appended. The UnixHTTPConnection instance would then remove the
known socket path from the URL.

This relied on all calls going through the HTTPConnection.request()
function, where the URL could be rewritten. In the case of 'chunked'
HTTP POST requests this doesn't happen, so such calls would request
a path still including the socket path and would receive a 404 error.

The client now constructs URLs containing just the path of the desired API
endpoint, and expects the Unix socket transport to know the path to the
Docker daemon's socket.

docker/client.py

@@ -42,31 +42,35 @@ class Client(requests.Session):
     def __init__(self, base_url=None, version=DEFAULT_DOCKER_API_VERSION,
                  timeout=DEFAULT_TIMEOUT_SECONDS, tls=False):
         super(Client, self).__init__()
-        base_url = utils.parse_host(base_url)
-        if 'http+unix:///' in base_url:
-            base_url = base_url.replace('unix:/', 'unix:')
+
         if tls and not base_url.startswith('https://'):
             raise errors.TLSParameterError(
                 'If using TLS, the base_url argument must begin with '
                 '"https://".')
+
         if not isinstance(version, six.string_types):
             raise errors.DockerException(
                 'version parameter must be a string. Found {0}'.format(
                     type(version).__name__
                 )
             )
-        self.base_url = base_url
+
         self._version = version
         self._timeout = timeout
         self._auth_configs = auth.load_config()
 
-        # Use SSLAdapter for the ability to specify SSL version
-        if isinstance(tls, TLSConfig):
-            tls.configure_client(self)
-        elif tls:
-            self.mount('https://', ssladapter.SSLAdapter())
+        base_url = utils.parse_host(base_url)
+        if base_url.startswith('http+unix://'):
+            unix_socket_adapter = unixconn.UnixAdapter(base_url, timeout)
+            self.mount('http+docker://', unix_socket_adapter)
+            self.base_url = 'http+docker://localunixsocket'
         else:
-            self.mount('http+unix://', unixconn.UnixAdapter(base_url, timeout))
+            # Use SSLAdapter for the ability to specify SSL version
+            if isinstance(tls, TLSConfig):
+                tls.configure_client(self)
+            elif tls:
+                self.mount('https://', ssladapter.SSLAdapter())
+            self.base_url = base_url
 
     def _set_request_timeout(self, kwargs):
         """Prepare the kwargs for an HTTP request by inserting the timeout

docker/unixconn/unixconn.py

@@ -41,17 +41,9 @@ class UnixHTTPConnection(httplib.HTTPConnection, object):
     def connect(self):
         sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
         sock.settimeout(self.timeout)
-        sock.connect(self.base_url.replace("http+unix:/", ""))
+        sock.connect(self.unix_socket)
         self.sock = sock
 
-    def _extract_path(self, url):
-        # remove the base_url entirely..
-        return url.replace(self.base_url, "")
-
-    def request(self, method, url, **kwargs):
-        url = self._extract_path(self.unix_socket)
-        super(UnixHTTPConnection, self).request(method, url, **kwargs)
-
 
 class UnixHTTPConnectionPool(connectionpool.HTTPConnectionPool):
     def __init__(self, base_url, socket_path, timeout=60):
@@ -67,23 +59,26 @@ class UnixHTTPConnectionPool(connectionpool.HTTPConnectionPool):
 
 
 class UnixAdapter(requests.adapters.HTTPAdapter):
-    def __init__(self, base_url, timeout=60):
-        self.base_url = base_url
+    def __init__(self, socket_url, timeout=60):
+        socket_path = socket_url.replace('http+unix://', '')
+        if not socket_path.startswith('/'):
+            socket_path = '/' + socket_path
+        self.socket_path = socket_path
         self.timeout = timeout
         self.pools = RecentlyUsedContainer(10,
                                            dispose_func=lambda p: p.close())
         super(UnixAdapter, self).__init__()
 
-    def get_connection(self, socket_path, proxies=None):
+    def get_connection(self, url, proxies=None):
         with self.pools.lock:
-            pool = self.pools.get(socket_path)
+            pool = self.pools.get(url)
             if pool:
                 return pool
 
-            pool = UnixHTTPConnectionPool(self.base_url,
-                                          socket_path,
+            pool = UnixHTTPConnectionPool(url,
+                                          self.socket_path,
                                           self.timeout)
-            self.pools[socket_path] = pool
+            self.pools[url] = pool
 
         return pool
 

tests/fake_api.py

@@ -324,7 +324,7 @@ def post_fake_tag_image():
 
 
 # Maps real api url to fake response callback
-prefix = 'http+unix://var/run/docker.sock'
+prefix = 'http+docker://localunixsocket'
 fake_responses = {
     '{1}/{0}/version'.format(CURRENT_VERSION, prefix):
     get_fake_version,

tests/test.py

@@ -71,7 +71,7 @@ def fake_resp(url, data=None, **kwargs):
 
 
 fake_request = mock.Mock(side_effect=fake_resp)
-url_prefix = 'http+unix://var/run/docker.sock/v{0}/'.format(
+url_prefix = 'http+docker://localunixsocket/v{0}/'.format(
     docker.client.DEFAULT_DOCKER_API_VERSION)
 
 
@@ -1267,20 +1267,24 @@ class DockerClientTest(Cleanup, unittest.TestCase):
             timeout=None
         )
 
+    def _socket_path_for_client_session(self, client):
+        socket_adapter = client.get_adapter('http+docker://')
+        return socket_adapter.socket_path
+
     def test_url_compatibility_unix(self):
         c = docker.Client(base_url="unix://socket")
 
-        assert c.base_url == "http+unix://socket"
+        assert self._socket_path_for_client_session(c) == '/socket'
 
     def test_url_compatibility_unix_triple_slash(self):
         c = docker.Client(base_url="unix:///socket")
 
-        assert c.base_url == "http+unix://socket"
+        assert self._socket_path_for_client_session(c) == '/socket'
 
     def test_url_compatibility_http_unix_triple_slash(self):
         c = docker.Client(base_url="http+unix:///socket")
 
-        assert c.base_url == "http+unix://socket"
+        assert self._socket_path_for_client_session(c) == '/socket'
 
     def test_url_compatibility_http(self):
         c = docker.Client(base_url="http://hostname:1234")