Add a console output action to servers

Relates to blueprint osapi-console-log and bug 876809. Adds equivalent
of euca-get-console-output to openstack api as an extension.

Change-Id: Ia71361ebbec820616a3007e216b0b9ff98d43541

8 files changed, 164 insertions, 8 deletions

diff --git a/nova/api/openstack/v2/contrib/console_output.py b/nova/api/openstack/v2/contrib/console_output.py
new file mode 100644
index 000000000..32bd3a5fb
--- /dev/null
+++ b/nova/api/openstack/v2/contrib/console_output.py
@@ -0,0 +1,60 @@
+# vim: tabstop=4 shiftwidth=4 softtabstop=4
+
+# Copyright 2011 OpenStack LLC.
+# Copyright 2011 Grid Dynamics
+# Copyright 2011 Eldar Nugaev, Kirill Shileev, Ilya Alekseyev
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    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 webob
+
+from nova import compute
+from nova import exception
+from nova import log as logging
+from nova.api.openstack.v2 import extensions
+
+
+LOG = logging.getLogger('nova.api.openstack.v2.contrib.console_output')
+
+
+class Console_output(extensions.ExtensionDescriptor):
+    """Console log output support, with tailing ability."""
+
+    name = "Console_output"
+    alias = "os-console-output"
+    namespace = "http://docs.openstack.org/ext/os-console-output/api/v2"
+    updated = "2011-12-08T00:00:00+00:00"
+
+    def __init__(self, ext_mgr):
+        self.compute_api = compute.API()
+        super(Console_output, self).__init__(ext_mgr)
+
+    def get_console_output(self, input_dict, req, server_id):
+        """Get text console output."""
+        context = req.environ['nova.context']
+        length = input_dict['os-getConsoleOutput'].get('length')
+        try:
+            return self.compute_api.get_console_output(context,
+                                                       server_id,
+                                                       length)
+        except exception.ApiError, e:
+            raise webob.exc.HTTPBadRequest(explanation=e.message)
+        except exception.NotAuthorized, e:
+            raise webob.exc.HTTPUnauthorized()
+
+    def get_actions(self):
+        """Return the actions the extension adds, as required by contract."""
+        actions = [extensions.ActionExtension("servers", "os-getConsoleOutput",
+                                              self.get_console_output)]
+
+        return actions
diff --git a/nova/compute/api.py b/nova/compute/api.py
index 0fd55f97d..bfeb60a7a 100644
--- a/nova/compute/api.py
+++ b/nova/compute/api.py
@@ -1486,11 +1486,12 @@ class API(base.Base):
                        'hostignore',
                        'portignore')}
 
-    def get_console_output(self, context, instance):
+    def get_console_output(self, context, instance, tail_length=None):
         """Get console output for an an instance."""
         return self._call_compute_message('get_console_output',
                                           context,
-                                          instance)
+                                          instance,
+                                          {'tail_length': tail_length})
 
     def lock(self, context, instance):
         """Lock the given instance."""
diff --git a/nova/compute/manager.py b/nova/compute/manager.py
index d6912bb56..1abcf842e 100644
--- a/nova/compute/manager.py
+++ b/nova/compute/manager.py
@@ -1377,15 +1377,30 @@ class ComputeManager(manager.SchedulerDependentManager):
         self.driver.inject_network_info(instance, network_info)
 
     @exception.wrap_exception(notifier=notifier, publisher_id=publisher_id())
-    def get_console_output(self, context, instance_uuid):
+    def get_console_output(self, context, instance_uuid, tail_length=None):
         """Send the console output for the given instance."""
         context = context.elevated()
         instance_ref = self.db.instance_get_by_uuid(context, instance_uuid)
         LOG.audit(_("Get console output for instance %s"), instance_uuid,
                   context=context)
         output = self.driver.get_console_output(instance_ref)
+
+        if tail_length is not None:
+            output = self._tail_log(output, tail_length)
+
         return output.decode('utf-8', 'replace').encode('ascii', 'replace')
 
+    def _tail_log(self, log, length):
+        try:
+            length = int(length)
+        except ValueError:
+            length = 0
+
+        if length == 0:
+            return ''
+        else:
+            return '\n'.join(log.split('\n')[-int(length):])
+
     @exception.wrap_exception(notifier=notifier, publisher_id=publisher_id())
     def get_ajax_console(self, context, instance_uuid):
         """Return connection information for an ajax console."""
diff --git a/nova/tests/api/ec2/test_cloud.py b/nova/tests/api/ec2/test_cloud.py
index b44bd2322..7487db4a6 100644
--- a/nova/tests/api/ec2/test_cloud.py
+++ b/nova/tests/api/ec2/test_cloud.py
@@ -21,7 +21,6 @@ import copy
 import functools
 import os
 
-from eventlet import greenthread
 from M2Crypto import BIO
 from M2Crypto import RSA
 
@@ -1128,7 +1127,7 @@ class CloudTestCase(test.TestCase):
         output = self.cloud.get_console_output(context=self.context,
                                                instance_id=[instance_id])
         self.assertEquals(base64.b64decode(output['output']),
-                'FAKE CONSOLE?OUTPUT')
+                'FAKE CONSOLE OUTPUT\nANOTHER\nLAST LINE')
         # TODO(soren): We need this until we can stop polling in the rpc code
         #              for unit tests.
         rv = self.cloud.terminate_instances(self.context, [instance_id])
diff --git a/nova/tests/api/openstack/v2/contrib/test_console_output.py b/nova/tests/api/openstack/v2/contrib/test_console_output.py
new file mode 100644
index 000000000..bfe48ecea
--- /dev/null
+++ b/nova/tests/api/openstack/v2/contrib/test_console_output.py
@@ -0,0 +1,69 @@
+# Copyright 2011 Eldar Nugaev
+# All Rights Reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    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 json
+
+import webob
+
+from nova import compute
+from nova import test
+from nova.tests.api.openstack import fakes
+
+
+def fake_text_console_tail(self, method, context, instance_id, params):
+    tail_length = params['tail_length']
+    fixture = [str(i) for i in range(10)]
+
+    if tail_length is None:
+        pass
+    elif tail_length == 0:
+        fixture = []
+    else:
+        fixture = fixture[-int(tail_length):]
+
+    return '\n'.join(fixture)
+
+
+class ConsoleOutputExtensionTest(test.TestCase):
+
+    def setUp(self):
+        super(ConsoleOutputExtensionTest, self).setUp()
+
+    def test_get_text_console_instance_action(self):
+        self.stubs.Set(compute.API, '_call_compute_message',
+                       fake_text_console_tail)
+
+        body = {'os-getConsoleOutput': {}}
+        req = webob.Request.blank('/v1.1/123/servers/1/action')
+        req.method = "POST"
+        req.body = json.dumps(body)
+        req.headers["content-type"] = "application/json"
+
+        res = req.get_response(fakes.wsgi_app())
+        self.assertEqual(res.status_int, 200)
+
+    def test_get_console_output_with_tail(self):
+        self.stubs.Set(compute.API,
+                       '_call_compute_message',
+                       fake_text_console_tail)
+
+        body = {'os-getConsoleOutput': {'length': 3}}
+        req = webob.Request.blank('/v2/123/servers/1/action')
+        req.method = "POST"
+        req.body = json.dumps(body)
+        req.headers["content-type"] = "application/json"
+        res = req.get_response(fakes.wsgi_app())
+
+        self.assertEqual(res.status_int, 200)
diff --git a/nova/tests/api/openstack/v2/test_extensions.py b/nova/tests/api/openstack/v2/test_extensions.py
index 650770f50..2c29f6eed 100644
--- a/nova/tests/api/openstack/v2/test_extensions.py
+++ b/nova/tests/api/openstack/v2/test_extensions.py
@@ -98,6 +98,7 @@ class ExtensionControllerTest(ExtensionTestCase):
         super(ExtensionControllerTest, self).setUp()
         self.ext_list = [
             "AdminActions",
+            "Console_output",
             "Createserverext",
             "DeferredDelete",
             "DiskConfig",
diff --git a/nova/tests/test_compute.py b/nova/tests/test_compute.py
index b01344463..93eabae3d 100644
--- a/nova/tests/test_compute.py
+++ b/nova/tests/test_compute.py
@@ -588,9 +588,20 @@ class ComputeTestCase(BaseTestCase):
         instance = self._create_fake_instance()
         self.compute.run_instance(self.context, instance['uuid'])
 
-        console = self.compute.get_console_output(self.context,
+        output = self.compute.get_console_output(self.context,
                                                   instance['uuid'])
-        self.assert_(console)
+        self.assertEqual(output, 'FAKE CONSOLE OUTPUT\nANOTHER\nLAST LINE')
+        self.compute.terminate_instance(self.context, instance['uuid'])
+
+    def test_console_output_tail(self):
+        """Make sure we can get console output from instance"""
+        instance = self._create_fake_instance()
+        self.compute.run_instance(self.context, instance['uuid'])
+
+        output = self.compute.get_console_output(self.context,
+                                                instance['uuid'],
+                                                tail_length=2)
+        self.assertEqual(output, 'ANOTHER\nLAST LINE')
         self.compute.terminate_instance(self.context, instance['uuid'])
 
     def test_ajax_console(self):
diff --git a/nova/virt/fake.py b/nova/virt/fake.py
index c1e32be90..d25fe112e 100644
--- a/nova/virt/fake.py
+++ b/nova/virt/fake.py
@@ -218,7 +218,7 @@ class FakeConnection(driver.ComputeDriver):
         return [0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L]
 
     def get_console_output(self, instance):
-        return 'FAKE CONSOLE\xffOUTPUT'
+        return 'FAKE CONSOLE OUTPUT\nANOTHER\nLAST LINE'
 
     def get_ajax_console(self, instance):
         return {'token': 'FAKETOKEN',