Pick up proxy buildargs from environment

We currently support any buildarg via --build-args. This patch picks up
the default supported proxy buildargs if set in the user's environment,
to allow for more transparent proxy support.

The --build-args will take precendence.

DocImpact
Implements blueprint: better-proxy-support

Change-Id: I084e5d1cc8f9993d65167878f9983ad58a68e86e

kolla/cmd/build.py

@@ -204,6 +204,23 @@ class WorkerThread(Thread):
 
         return dest_archive
 
+    def update_buildargs(self):
+        buildargs = dict()
+        if self.conf.build_args:
+            buildargs = dict(self.conf.build_args)
+
+        proxy_vars = ('HTTP_PROXY', 'http_proxy', 'HTTPS_PROXY',
+                      'https_proxy', 'FTP_PROXY', 'ftp_proxy',
+                      'NO_PROXY', 'no_proxy')
+
+        for proxy_var in proxy_vars:
+            if proxy_var in os.environ and proxy_var not in buildargs:
+                buildargs[proxy_var] = os.environ.get(proxy_var)
+
+        if not buildargs:
+            return None
+        return buildargs
+
     def builder(self, image):
         LOG.debug('%s:Processing', image['name'])
         if image['status'] == 'unmatched':
@@ -256,13 +273,14 @@ class WorkerThread(Thread):
         pull = True if image['parent'] is None else False
 
         image['logs'] = str()
+        buildargs = self.update_buildargs()
         for response in self.dc.build(path=image['path'],
                                       tag=image['fullname'],
                                       nocache=self.nocache,
                                       rm=True,
                                       pull=pull,
                                       forcerm=self.forcerm,
-                                      buildargs=self.conf.build_args):
+                                      buildargs=buildargs):
             stream = json.loads(response.decode('utf-8'))
 
             if 'stream' in stream:

kolla/tests/test_build.py

@@ -12,6 +12,7 @@
 
 import fixtures
 import mock
+import os
 
 from kolla.cmd import build
 from kolla.tests import base
@@ -34,6 +35,7 @@ class WorkerThreadTest(base.TestCase):
         # NOTE(jeffrey4l): use a real, temporary dir
         FAKE_IMAGE['path'] = self.useFixture(fixtures.TempDir()).path
 
+    @mock.patch.dict(os.environ, clear=True)
     @mock.patch('docker.Client')
     def test_build_image(self, mock_client):
         queue = mock.Mock()
@@ -48,6 +50,7 @@ class WorkerThreadTest(base.TestCase):
             nocache=False, rm=True, pull=True, forcerm=True,
             buildargs=None)
 
+    @mock.patch.dict(os.environ, clear=True)
     @mock.patch('docker.Client')
     def test_build_image_with_build_arg(self, mock_client):
         build_args = {
@@ -64,3 +67,38 @@ class WorkerThreadTest(base.TestCase):
             path=FAKE_IMAGE['path'], tag=FAKE_IMAGE['fullname'],
             nocache=False, rm=True, pull=True, forcerm=True,
             buildargs=build_args)
+
+    @mock.patch.dict(os.environ, {'http_proxy': 'http://FROM_ENV:8080'},
+                     clear=True)
+    @mock.patch('docker.Client')
+    def test_build_arg_from_env(self, mock_client):
+        build_args = {
+            'http_proxy': 'http://FROM_ENV:8080',
+        }
+        worker = build.WorkerThread(mock.Mock(),
+                                    mock.Mock(),
+                                    self.conf)
+        worker.builder(FAKE_IMAGE)
+
+        mock_client().build.assert_called_once_with(
+            path=FAKE_IMAGE['path'], tag=FAKE_IMAGE['fullname'],
+            nocache=False, rm=True, pull=True, forcerm=True,
+            buildargs=build_args)
+
+    @mock.patch.dict(os.environ, {'http_proxy': 'http://FROM_ENV:8080'},
+                     clear=True)
+    @mock.patch('docker.Client')
+    def test_build_arg_precedence(self, mock_client):
+        build_args = {
+            'http_proxy': 'http://localhost:8080',
+        }
+        self.conf.set_override('build_args', build_args)
+        worker = build.WorkerThread(mock.Mock(),
+                                    mock.Mock(),
+                                    self.conf)
+        worker.builder(FAKE_IMAGE)
+
+        mock_client().build.assert_called_once_with(
+            path=FAKE_IMAGE['path'], tag=FAKE_IMAGE['fullname'],
+            nocache=False, rm=True, pull=True, forcerm=True,
+            buildargs=build_args)