Introduce `kuryr-k8s` service

This commit introduces the `kuryr-k8s` service by adding the service
binary and focusing on loading configuration options.

The configuration options are inherited from kuryr-lib project
(http://github.com/openstack/kuryr) and loaded at runtime, together with
the project ones.

These configuration options can be also generated using the
`oslo-config-generator` utility by using:

    tox -e genconfig

The service runs as any other OpenStack-based service:

    kuryr-k8s [--debug] [--config-file foo] ...

Partial-Implements: blueprint kuryr-k8s-integration
Change-Id: I7e52aef8fb2767dcc46317f2212f4285a17b11da
Signed-off-by: Jaume Devesa <devvesa@gmail.com>
Co-Authored-By: Taku Fukushima <f.tac.mac@gmail.com>

.gitignore

@@ -53,7 +53,6 @@ ChangeLog
 contrib/vagrant/.vagrant
 
 # Configuration files
-etc/kuryr.conf
 etc/kuryr.conf.sample
 
 # Ignore user specific local.conf settings for vagrant

etc/README-config.txt

@@ -0,0 +1,6 @@
+To generate the sample kuryr.conf file, run the following
+command from the top level of the kuryr directory:
+
+tox -e genconfig
+
+The sample file will be generated at etc/kuryr-k8s.conf.sample

etc/kuryr-k8s-config-generator.conf

@@ -0,0 +1,5 @@
+[DEFAULT]
+output_file = etc/kuryr.conf.sample
+wrap_width = 79
+namespace = kuryr_kubernetes
+namespace = kuryr_lib

kuryr_kubernetes/config.py

@@ -0,0 +1,65 @@
+# 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 os
+import sys
+
+from kuryr.lib._i18n import _, _LI
+from kuryr.lib import config as lib_config
+from oslo_config import cfg
+from oslo_log import log as logging
+
+from pbr import version as pbr_version
+
+LOG = logging.getLogger(__name__)
+
+kuryr_k8s_opts = [
+    cfg.StrOpt('pybasedir',
+        help=_('Directory where Kuryr-kubernetes python module is '
+               'installed.'),
+        default=os.path.abspath(
+            os.path.join(os.path.dirname(__file__),
+            '../../'))),
+]
+
+k8s_opts = [
+    cfg.StrOpt('api_root',
+        help=_("The root URL of the Kubernetes API"),
+        default=os.environ.get('K8S_API', 'http://localhost:8080')),
+]
+
+
+CONF = cfg.CONF
+
+CONF.register_opts(lib_config.core_opts)
+CONF.register_opts(lib_config.neutron_opts, group='neutron_client')
+CONF.register_opts(lib_config.keystone_opts, group='keystone_client')
+CONF.register_opts(lib_config.binding_opts, 'binding')
+
+CONF.register_opts(kuryr_k8s_opts)
+CONF.register_opts(k8s_opts, group='kubernetes')
+logging.register_options(CONF)
+
+
+def init(args, **kwargs):
+    version_k8s = pbr_version.VersionInfo('kuryr-kubernetes').version_string()
+    CONF(args=args, project='kuryr-k8s', version=version_k8s, **kwargs)
+
+
+def setup_logging():
+
+    logging.setup(CONF, 'kuryr-kubernetes')
+    logging.set_defaults(default_log_levels=logging.get_default_log_levels())
+    version_k8s = pbr_version.VersionInfo('kuryr-kubernetes').version_string()
+    LOG.info(_LI("Logging enabled!"))
+    LOG.info(_LI("%(prog)s version %(version)s"),
+             {'prog': sys.argv[0],
+              'version': version_k8s})

kuryr_kubernetes/opts.py

@@ -0,0 +1,39 @@
+# 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 copy
+
+from kuryr_kubernetes import config
+
+_kuryr_k8s_opts = [
+    ('kubernetes', config.k8s_opts),
+    ('kuryr-kubernetes', config.kuryr_k8s_opts),
+]
+
+
+def list_kuryr_opts():
+    """Return a list of oslo_config options available in Kuryr service.
+
+    Each element of the list is a tuple. The first element is the name of the
+    group under which the list of elements in the second element will be
+    registered. A group name of None corresponds to the [DEFAULT] group in
+    config files.
+
+    This function is also discoverable via the 'kuryr' entry point under
+    the 'oslo_config.opts' namespace.
+
+    The purpose of this is to allow tools like the Oslo sample config file
+    generator to discover the options exposed to users by Kuryr.
+
+    :returns: a list of (group_name, opts) tuples
+    """
+
+    return [(k, copy.deepcopy(o)) for k, o in _kuryr_k8s_opts]

kuryr_kubernetes/server.py

@@ -0,0 +1,59 @@
+# 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 sys
+import time
+
+from kuryr.lib._i18n import _LI
+from oslo_log import log as logging
+from oslo_service import service
+
+from kuryr_kubernetes import config
+
+
+LOG = logging.getLogger(__name__)
+
+
+class KuryrK8sService(service.Service):
+
+    def __init__(self):
+        super(KuryrK8sService, self).__init__()
+
+    def start(self):
+        # TODO(devvesa): Remove this line as soon as it does anything
+        LOG.info(_LI("I am doing nothing"))
+        try:
+            while(True):
+                time.sleep(5)
+                # TODO(devvesa): Remove this line as soon as does anything
+                LOG.info(_LI("Keep doing nothing"))
+        finally:
+            sys.exit(1)
+
+    def wait(self):
+        """Waits for K8sController to complete."""
+        super(KuryrK8sService, self).wait()
+
+    def stop(self, graceful=False):
+        """Stops the event loop if it's not stopped already."""
+        super(KuryrK8sService, self).stop(graceful)
+
+
+def start():
+    config.init(sys.argv[1:])
+    config.setup_logging()
+    kuryrk8s_launcher = service.launch(config.CONF, KuryrK8sService())
+    kuryrk8s_launcher.wait()
+
+
+if __name__ == '__main__':
+    start()

requirements.txt

@@ -2,16 +2,4 @@
 # of appearance. Changing the order has an impact on the overall integration
 # process, which may cause wedges in the gate later.
 
-pbr>=1.6 # Apache-2.0
-Babel>=2.3.4 # BSD
-Flask<1.0,>=0.10 # BSD
-jsonschema!=2.5.0,<3.0.0,>=2.0.0 # MIT
-netaddr!=0.7.16,>=0.7.12 # BSD
-oslo.concurrency>=3.8.0 # Apache-2.0
-oslo.log>=1.14.0 # Apache-2.0
-oslo.serialization>=1.10.0 # Apache-2.0
-oslo.utils>=3.5.0 # Apache-2.0
-python-neutronclient>=4.2.0 # Apache-2.0
-pyroute2>=0.3.10 # Apache-2.0 (+ dual licensed GPL2)
-os-client-config>=1.13.1 # Apache-2.0
-neutron-lib>=0.1.0 # Apache-2.0
+-e git://github.com/openstack/kuryr.git@master#egg=kuryr_lib

setup.cfg

@@ -13,15 +13,20 @@ classifier =
     License :: OSI Approved :: Apache Software License
     Operating System :: POSIX :: Linux
     Programming Language :: Python
-    Programming Language :: Python :: 2
-    Programming Language :: Python :: 2.7
     Programming Language :: Python :: 3
-    Programming Language :: Python :: 3.3
     Programming Language :: Python :: 3.4
 
+[entry_points]
+oslo.config.opts =
+    kuryr_kubernetes = kuryr_kubernetes.opts:list_kuryr_opts
+    kuryr_lib = kuryr.lib.opts:list_kuryr_opts
+
+console_scripts =
+    kuryr-k8s = kuryr_kubernetes.server:start
+
 [files]
 packages =
-    kuryr-kubernetes
+    kuryr_kubernetes
 
 [build_sphinx]
 source-dir = doc/source

tox.ini

@@ -73,4 +73,4 @@ import_exceptions = neutron.i18n
 local-check-factory = neutron_lib.hacking.checks.factory
 
 [testenv:genconfig]
-commands = oslo-config-generator --config-file=etc/kuryr-config-generator.conf
+commands = oslo-config-generator --config-file=etc/kuryr-k8s-config-generator.conf