[lxc-devel] [pylxd/master] Image export
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lxc-bot at linuxcontainers.org
Wed Sep 28 23:11:09 UTC 2016
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From 47689a1dd77f1842f47d09ba7b10e6761fbdd031 Mon Sep 17 00:00:00 2001
From: Paul Hummer <paul.hummer at canonical.com>
Date: Wed, 28 Sep 2016 14:35:49 -0600
Subject: [PATCH 1/4] Update the apt cache in the integration test run before
installing packages
---
run_integration_tests | 1 +
1 file changed, 1 insertion(+)
diff --git a/run_integration_tests b/run_integration_tests
index 54380e5..cdba3ee 100755
--- a/run_integration_tests
+++ b/run_integration_tests
@@ -8,6 +8,7 @@ CONTAINER_NAME=pylxd-`uuidgen | cut -d"-" -f1`
# a bug in LXD).
lxc launch $CONTAINER_IMAGE $CONTAINER_NAME -c security.nesting=true -c security.privileged=true
sleep 5 # Wait for the network to come up
+lxc exec $CONTAINER_NAME -- apt-get update
lxc exec $CONTAINER_NAME -- apt-get install -y tox python3-dev libssl-dev libffi-dev build-essential
lxc exec $CONTAINER_NAME -- mkdir -p /opt/pylxd
From a66b49f114d6bf3c14b6f0392e8b56a176a6dc96 Mon Sep 17 00:00:00 2001
From: Paul Hummer <paul.hummer at canonical.com>
Date: Wed, 28 Sep 2016 14:45:10 -0600
Subject: [PATCH 2/4] Return a file-like object from Image.export
The buffered image is written to a temporary file on disk. It also
required a little bit of massaging on the response assertion code
to not try and read response content when the response is streamed.
Fixes #183
---
integration/test_images.py | 4 ++--
pylxd/client.py | 6 +++++-
pylxd/models/image.py | 25 +++++++++++++++++--------
3 files changed, 24 insertions(+), 11 deletions(-)
diff --git a/integration/test_images.py b/integration/test_images.py
index 9882fac..f1a7473 100644
--- a/integration/test_images.py
+++ b/integration/test_images.py
@@ -85,8 +85,8 @@ def test_delete(self):
self.client.images.get, self.image.fingerprint)
def test_export(self):
- """The imerage is successfully exported."""
- data = self.image.export()
+ """The image is successfully exported."""
+ data = self.image.export().read()
data_sha = hashlib.sha256(data).hexdigest()
self.assertEqual(self.image.fingerprint, data_sha)
diff --git a/pylxd/client.py b/pylxd/client.py
index 4930f76..c25848e 100644
--- a/pylxd/client.py
+++ b/pylxd/client.py
@@ -91,7 +91,11 @@ def netloc(self):
def get(self, *args, **kwargs):
"""Perform an HTTP GET."""
response = self.session.get(self._api_endpoint, *args, **kwargs)
- self._assert_response(response)
+
+ # In the case of streaming, we can't validate the json the way we
+ # would with normal HTTP responses, so just ignore that entirely.
+ if not kwargs.get('stream', False):
+ self._assert_response(response)
return response
def post(self, *args, **kwargs):
diff --git a/pylxd/models/image.py b/pylxd/models/image.py
index fbf2e43..2293dd9 100644
--- a/pylxd/models/image.py
+++ b/pylxd/models/image.py
@@ -11,7 +11,9 @@
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
+import contextlib
import hashlib
+import tempfile
from pylxd.models import _model as model
from pylxd.models.operation import Operation
@@ -97,8 +99,7 @@ def create(cls, client, image_data, public=False, wait=False):
@classmethod
def create_from_simplestreams(cls, client, server, alias,
public=False, auto_update=False):
- """ Copy an image from simplestreams.
- """
+ """Copy an image from simplestreams."""
config = {
'public': public,
'auto_update': auto_update,
@@ -119,8 +120,7 @@ def create_from_simplestreams(cls, client, server, alias,
@classmethod
def create_from_url(cls, client, url,
public=False, auto_update=False):
- """ Copy an image from an url.
- """
+ """Copy an image from an url."""
config = {
'public': public,
'auto_update': auto_update,
@@ -137,9 +137,18 @@ def create_from_url(cls, client, url,
return client.images.get(op.metadata['fingerprint'])
def export(self):
- """Export the image."""
- response = self.api.export.get()
- return response.content
+ """Export the image.
+
+ Because the image itself may be quite large, we stream the download
+ in 1kb chunks, and write it to a temporary file on disk. Once that
+ file is closed, it is deleted from the disk.
+ """
+ on_disk = tempfile.TemporaryFile()
+ with contextlib.closing(self.api.export.get(stream=True)) as response:
+ for chunk in response.iter_content(chunk_size=1024):
+ on_disk.write(chunk)
+ on_disk.seek(0)
+ return on_disk
def add_alias(self, name, description):
"""Add an alias to the image."""
@@ -168,7 +177,7 @@ def delete_alias(self, name):
pass
def copy(self, new_client, public=None, auto_update=None, wait=False):
- """ Copy an image to a another LXD.
+ """Copy an image to a another LXD.
Destination host information is contained in the client
connection passed in.
From 5c638fc10d57323a43473a982281eca550de8ba2 Mon Sep 17 00:00:00 2001
From: Paul Hummer <paul.hummer at canonical.com>
Date: Wed, 28 Sep 2016 17:06:21 -0600
Subject: [PATCH 3/4] Add documentation for the new Image.export API.
---
doc/source/images.rst | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/doc/source/images.rst b/doc/source/images.rst
index 88f915e..982aa1d 100644
--- a/doc/source/images.rst
+++ b/doc/source/images.rst
@@ -53,8 +53,10 @@ the `LXD documentation`_.
Image methods
-------------
- - `export` - Export the image. Returns binary data that is the
- image itself.
+ - `export` - Export the image. Returns a file object with the contents
+ of the image. *Note: Prior to pylxd 2.1.1, this method returned a
+ bytestring with data; as it was not unbuffered, the API was severely
+ limited.*
- `add_alias` - Add an alias to the image.
From e7a5721c023d080609458a592b0f4b70fb418f8b Mon Sep 17 00:00:00 2001
From: Paul Hummer <paul.hummer at canonical.com>
Date: Wed, 28 Sep 2016 17:06:45 -0600
Subject: [PATCH 4/4] Add integration tests for container.publish
---
integration/test_containers.py | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/integration/test_containers.py b/integration/test_containers.py
index 830ff7b..88589df 100644
--- a/integration/test_containers.py
+++ b/integration/test_containers.py
@@ -152,3 +152,11 @@ def test_execute(self):
stdout, stderr = self.container.execute(['echo', 'test'])
self.assertEqual('test\n', stdout)
+
+ def test_publish(self):
+ """A container is published."""
+ image = self.container.publish(wait=True)
+
+ self.assertIn(
+ image.fingerprint,
+ [i.fingerprint for i in self.client.images.all()])
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