Repository: docker/docker-py

Issue:
logs() separate param for stream and follow
From: https://github.com/docker/compose/pull/2720/files#r52222296

Current the `follow` param is set based on `stream`

I think `follow=True` does imply `stream=True`, but `stream=True` doesn't imply `follow=True`, you may still want to stream without following.

Discussion:
dnephin: Looks good, just one consideration for backwards compatibility.

Patch:
diff --git a/docker/api/container.py b/docker/api/container.py
index ceac173f..8aa9aa2c 100644
--- a/docker/api/container.py
+++ b/docker/api/container.py
@@ -193,12 +193,14 @@ class ContainerApiMixin(object):
 
     @utils.check_resource
     def logs(self, container, stdout=True, stderr=True, stream=False,
-             timestamps=False, tail='all', since=None):
+             timestamps=False, tail='all', since=None, follow=None):
         if utils.compare_version('1.11', self._version) >= 0:
+            if follow is None:
+                follow = stream
             params = {'stderr': stderr and 1 or 0,
                       'stdout': stdout and 1 or 0,
                       'timestamps': timestamps and 1 or 0,
-                      'follow': stream and 1 or 0,
+                      'follow': follow and 1 or 0,
                       }
             if utils.compare_version('1.13', self._version) >= 0:
                 if tail != 'all' and (not isinstance(tail, int) or tail < 0):
diff --git a/docs/api.md b/docs/api.md
index 00ccabca..32952bf3 100644
--- a/docs/api.md
+++ b/docs/api.md
@@ -677,6 +677,7 @@ output as it happens.
 * timestamps (bool): Show timestamps
 * tail (str or int): Output specified number of lines at the end of logs: `"all"` or `number`. Default `"all"`
 * since (datetime or int): Show logs since a given datetime or integer epoch (in seconds)
+* follow (bool): Follow log output
 
 **Returns** (generator or str):
 


Test patch:
diff --git a/tests/integration/container_test.py b/tests/integration/container_test.py
index 1714599b..142299d3 100644
--- a/tests/integration/container_test.py
+++ b/tests/integration/container_test.py
@@ -666,7 +666,7 @@ Line2'''
         logs = self.client.logs(id, tail=1)
         self.assertEqual(logs, 'Line2\n'.encode(encoding='ascii'))
 
-    def test_logs_streaming(self):
+    def test_logs_streaming_and_follow(self):
         snippet = 'Flowering Nights (Sakuya Iyazoi)'
         container = self.client.create_container(
             BUSYBOX, 'echo {0}'.format(snippet)
@@ -675,7 +675,7 @@ Line2'''
         self.tmp_containers.append(id)
         self.client.start(id)
         logs = six.binary_type()
-        for chunk in self.client.logs(id, stream=True):
+        for chunk in self.client.logs(id, stream=True, follow=True):
             logs += chunk
 
         exitcode = self.client.wait(id)
diff --git a/tests/unit/container_test.py b/tests/unit/container_test.py
index c2b25734..d66eeede 100644
--- a/tests/unit/container_test.py
+++ b/tests/unit/container_test.py
@@ -1119,6 +1119,36 @@ class ContainerTest(DockerClientTest):
         )
 
     def test_log_streaming(self):
+        with mock.patch('docker.Client.inspect_container',
+                        fake_inspect_container):
+            self.client.logs(fake_api.FAKE_CONTAINER_ID, stream=True,
+                             follow=False)
+
+        fake_request.assert_called_with(
+            'GET',
+            url_prefix + 'containers/3cc2351ab11b/logs',
+            params={'timestamps': 0, 'follow': 0, 'stderr': 1, 'stdout': 1,
+                    'tail': 'all'},
+            timeout=DEFAULT_TIMEOUT_SECONDS,
+            stream=True
+        )
+
+    def test_log_following(self):
+        with mock.patch('docker.Client.inspect_container',
+                        fake_inspect_container):
+            self.client.logs(fake_api.FAKE_CONTAINER_ID, stream=False,
+                             follow=True)
+
+        fake_request.assert_called_with(
+            'GET',
+            url_prefix + 'containers/3cc2351ab11b/logs',
+            params={'timestamps': 0, 'follow': 1, 'stderr': 1, 'stdout': 1,
+                    'tail': 'all'},
+            timeout=DEFAULT_TIMEOUT_SECONDS,
+            stream=False
+        )
+
+    def test_log_following_backwards(self):
         with mock.patch('docker.Client.inspect_container',
                         fake_inspect_container):
             self.client.logs(fake_api.FAKE_CONTAINER_ID, stream=True)
@@ -1132,12 +1162,27 @@ class ContainerTest(DockerClientTest):
             stream=True
         )
 
+    def test_log_streaming_and_following(self):
+        with mock.patch('docker.Client.inspect_container',
+                        fake_inspect_container):
+            self.client.logs(fake_api.FAKE_CONTAINER_ID, stream=True,
+                             follow=True)
+
+        fake_request.assert_called_with(
+            'GET',
+            url_prefix + 'containers/3cc2351ab11b/logs',
+            params={'timestamps': 0, 'follow': 1, 'stderr': 1, 'stdout': 1,
+                    'tail': 'all'},
+            timeout=DEFAULT_TIMEOUT_SECONDS,
+            stream=True
+        )
+
     def test_log_tail(self):
 
         with mock.patch('docker.Client.inspect_container',
                         fake_inspect_container):
             self.client.logs(fake_api.FAKE_CONTAINER_ID, stream=False,
-                             tail=10)
+                             follow=False, tail=10)
 
         fake_request.assert_called_with(
             'GET',
@@ -1153,7 +1198,7 @@ class ContainerTest(DockerClientTest):
         with mock.patch('docker.Client.inspect_container',
                         fake_inspect_container):
             self.client.logs(fake_api.FAKE_CONTAINER_ID, stream=False,
-                             since=ts)
+                             follow=False, since=ts)
 
         fake_request.assert_called_with(
             'GET',
@@ -1170,7 +1215,7 @@ class ContainerTest(DockerClientTest):
         with mock.patch('docker.Client.inspect_container',
                         fake_inspect_container):
             self.client.logs(fake_api.FAKE_CONTAINER_ID, stream=False,
-                             since=time)
+                             follow=False, since=time)
 
         fake_request.assert_called_with(
             'GET',
@@ -1188,7 +1233,7 @@ class ContainerTest(DockerClientTest):
             with mock.patch('docker.Client._stream_raw_result',
                             m):
                 self.client.logs(fake_api.FAKE_CONTAINER_ID,
-                                 stream=True)
+                                 follow=True, stream=True)
 
         self.assertTrue(m.called)
         fake_request.assert_called_with(