Allow for pull as an option to docker build

docker/client.py

@@ -408,7 +408,7 @@ def attach_socket(self, container, params=None, ws=False):
 
     def build(self, path=None, tag=None, quiet=False, fileobj=None,
               nocache=False, rm=False, stream=False, timeout=None,
-              custom_context=False, encoding=None):
+              custom_context=False, encoding=None, pull=True):
         remote = context = headers = None
         if path is None and fileobj is None:
             raise TypeError("Either path or fileobj needs to be provided.")
@@ -441,7 +441,8 @@ def build(self, path=None, tag=None, quiet=False, fileobj=None,
             'remote': remote,
             'q': quiet,
             'nocache': nocache,
-            'rm': rm
+            'rm': rm,
+            'pull': pull
         }
 
         if context is not None:

docs/api.md

@@ -58,6 +58,7 @@ build output as it happens
 * timeout (int): HTTP timeout
 * custom_context (bool): Optional if using `fileobj`
 * encoding (str): The encoding for a stream. Set to `gzip` for compressing
+* pull (bool): Downloads any updates to the FROM image in Dockerfiles
 
 **Returns** (generator): A generator of the build output
 

tests/test.py

@@ -1677,6 +1677,20 @@ def test_build_container(self):
         except Exception as e:
             self.fail('Command should not raise exception: {0}'.format(e))
 
+    def test_build_container_pull(self):
+        script = io.BytesIO('\n'.join([
+            'FROM busybox',
+            'MAINTAINER docker-py',
+            'RUN mkdir -p /tmp/test',
+            'EXPOSE 8080',
+            'ADD https://dl.dropboxusercontent.com/u/20637798/silence.tar.gz'
+            ' /tmp/silence.tar.gz'
+        ]).encode('ascii'))
+        try:
+            self.client.build(fileobj=script, pull=True)
+        except Exception as e:
+            self.fail('Command should not raise exception: {0}'.format(e))
+
     def test_build_container_stream(self):
         script = io.BytesIO('\n'.join([
             'FROM busybox',