add some convenient OF-Config classes

some python classes for a set of OF-Config 1.1.1 types.

the goal is to allow programmers use OF-Config without direct
XML manipulations.

Signed-off-by: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>

3 files changed, 333 insertions, 0 deletions

diff --git a/ryu/lib/of_config/base.py b/ryu/lib/of_config/base.py
new file mode 100644
index 00000000..bb467f77
--- /dev/null
+++ b/ryu/lib/of_config/base.py
@@ -0,0 +1,144 @@
+# Copyright (C) 2013 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2013 YAMAMOTO Takashi <yamamoto at valinux co jp>
+#
+# 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.
+
+# convenient classes to manipulate OF-Config XML
+# in a little more pythonic way.
+# currently assuming OF-Config 1.1.1.
+
+from ryu.lib import stringify
+
+from lxml import objectify
+import lxml.etree as ET
+
+
+_ns_of111 = 'urn:onf:of111:config:yang'
+_ns_netconf = 'urn:ietf:params:xml:ns:netconf:base:1.0'
+_nsmap = {
+    'of111': _ns_of111,
+    'nc': _ns_netconf,
+}
+
+
+def _pythonify(name):
+    return name.replace('-', '_')
+
+
+class _e(object):
+    def __init__(self, name, is_list):
+        self.name = name
+        self.cls = None
+        self.is_list = is_list
+
+
+# complexType
+class _ct(_e):
+    def __init__(self, name, cls, is_list):
+        super(_ct, self).__init__(name, is_list)
+        self.cls = cls
+
+
+class _Base(stringify.StringifyMixin):
+    _M = objectify.ElementMaker(annotate=False,
+                                namespace=_ns_of111,
+                                nsmap=_nsmap)
+
+    def __init__(self, **kwargs):
+        for e in self._ELEMENTS:
+            k = _pythonify(e.name)
+            try:
+                v = kwargs.pop(k)
+            except KeyError:
+                if e.is_list:
+                    v = []
+                else:
+                    v = None
+            setattr(self, k, v)
+        if kwargs:
+            raise TypeError('unknown kwargs %s' % kwargs)
+
+    def to_et(self, tag):
+        def convert(v):
+            if isinstance(v, _Base):
+                return v.to_et(e.name)
+            elif isinstance(v, objectify.ObjectifiedElement):
+                assert ET.QName(v.tag).localname == itag
+                return v
+            return self._M(itag, v)
+
+        args = []
+        for e in self._ELEMENTS:
+            itag = e.name
+            k = _pythonify(itag)
+            v = getattr(self, k)
+            if v is None:
+                continue
+            if isinstance(v, list):
+                assert e.is_list
+                ele = map(convert, v)
+            else:
+                assert not e.is_list
+                ele = [convert(v)]
+            args.extend(ele)
+        return self._M(tag, *args)
+
+    def to_xml(self, tag):
+        e = self.to_et(tag)
+        return ET.tostring(e, pretty_print=True)
+
+    @classmethod
+    def from_xml(cls, xmlstring):
+        et = objectify.fromstring(xmlstring)
+        return cls.from_et(et)
+
+    @classmethod
+    def from_et(cls, et):
+        def convert(v):
+            if not e.cls is None:
+                return e.cls.from_et(v)
+            return v
+
+        kwargs = {}
+        for e in cls._ELEMENTS:
+            try:
+                v = et[e.name]
+            except AttributeError:
+                continue
+            assert isinstance(v, objectify.ObjectifiedElement)
+            if len(v) == 1:
+                v = convert(v)
+                if e.is_list:
+                    v = [v]
+            else:
+                assert e.is_list
+                v = map(convert, v)
+            k = _pythonify(e.name)
+            assert not k in kwargs
+            kwargs[k] = v
+        return cls(**kwargs)
+
+
+class _Unimpl(_Base):
+    _ELEMENTS = [
+        _e('raw_et', is_list=False),
+    ]
+
+    def to_et(self, tag):
+        assert self.raw_et.tag == tag
+        return self.raw_et
+
+    @classmethod
+    def from_et(cls, et):
+        return cls(raw_et=et)
diff --git a/ryu/lib/of_config/classes.py b/ryu/lib/of_config/classes.py
new file mode 100644
index 00000000..e747186e
--- /dev/null
+++ b/ryu/lib/of_config/classes.py
@@ -0,0 +1,35 @@
+# Copyright (C) 2013 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2013 YAMAMOTO Takashi <yamamoto at valinux co jp>
+#
+# 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.
+
+# convenient classes to manipulate OF-Config XML
+# in a little more pythonic way.
+# currently assuming OF-Config 1.1.1.
+
+from ryu.lib import stringify
+
+
+from .base import _Base, _ct, _e, _ns_netconf
+from .generated_classes import *
+
+
+# probably should not be here but for convenience
+class NETCONF_Config(_Base):
+    _ELEMENTS = [
+        _ct('capable-switch', OFCapableSwitchType, is_list=False),
+    ]
+
+    def to_xml(self):
+        return super(NETCONF_Config, self).to_xml('{%s}config' % _ns_netconf)
diff --git a/ryu/lib/of_config/generated_classes.py b/ryu/lib/of_config/generated_classes.py
new file mode 100644
index 00000000..83e41019
--- /dev/null
+++ b/ryu/lib/of_config/generated_classes.py
@@ -0,0 +1,154 @@
+# Copyright (C) 2013 Nippon Telegraph and Telephone Corporation.
+# Copyright (C) 2013 YAMAMOTO Takashi <yamamoto at valinux co jp>
+#
+# 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.
+
+# NOTE: this file is intendend to be replaced with mechanically generated
+# file if/when OF-Config yang specification is available with a suitable
+# license.
+
+from ryu.lib.of_config.base import _Base, _e, _ct
+
+
+class OFPortConfigurationType(_Base):
+    _ELEMENTS = [
+        _e('admin-state', is_list=False),
+        _e('no-receive', is_list=False),
+        _e('no-forward', is_list=False),
+        _e('no-packet-in', is_list=False),
+    ]
+
+
+class OFPortType(_Base):
+    _ELEMENTS = [
+        _e('resource-id', is_list=False),
+        _e('number', is_list=False),
+        _e('name', is_list=False),
+        _e('current-rate', is_list=False),
+        _e('max-rate', is_list=False),
+        _ct('configuration', OFPortConfigurationType, is_list=False),
+        _ct('state', None, is_list=False),
+        _ct('features', None, is_list=False),
+        _ct('tunnel-type', None, is_list=False),
+    ]
+
+
+class OFQueuePropertiesType(_Base):
+    _ELEMENTS = [
+        _e('min-rate', is_list=False),
+        _e('max-rate', is_list=False),
+        _e('experimenter', is_list=True),
+    ]
+
+
+class OFQueueType(_Base):
+    _ELEMENTS = [
+        _e('resource-id', is_list=False),
+        _e('id', is_list=False),
+        _e('port', is_list=False),
+        _ct('properties', OFQueuePropertiesType, is_list=False),
+    ]
+
+
+class OFCapableSwitchResourcesType(_Base):
+    _ELEMENTS = [
+        _ct('port', OFPortType, is_list=True),
+        _ct('queue', OFQueueType, is_list=True),
+        _ct('owned-certificate', None, is_list=True),
+        _ct('external-certificate', None, is_list=True),
+        _ct('flow-table', None, is_list=True),
+    ]
+
+
+class OFControllerStateType(_Base):
+    _ELEMENTS = [
+        _e('connection-state', is_list=False),
+        _e('current-version', is_list=False),
+
+        # XXX OF-Config 1.1.1 is inconsistent about supported-versions.
+        #
+        # according to its xml schema (p.43), i believe this should look
+        # like the following.  it's what linc/of_config does, too.
+        #     <supported-versions>1.3</supported-versions>
+        #
+        # on the other hand, it has an example (p.45) like the following.
+        # this one is compatible with OF-Config 1.1.
+        #     <supported-versions>
+        #         <version>1.2</version>
+        #         <version>1.1</version>
+        #     </supported-versions>
+
+        _e('supported-versions', is_list=True),
+        _e('local-ip-address-in-use', is_list=False),
+        _e('local-port-in-use', is_list=False),
+    ]
+
+
+class OFControllerType(_Base):
+    _ELEMENTS = [
+        _e('id', is_list=False),
+        _e('role', is_list=False),
+        _e('ip-address', is_list=False),
+        _e('port', is_list=False),
+        _e('local-ip-address', is_list=False),
+        _e('local-port', is_list=False),
+        _e('protocol', is_list=False),
+        _ct('state', OFControllerStateType, is_list=False),
+    ]
+
+
+class OFLogicalSwitchControllersType(_Base):
+    _ELEMENTS = [
+        _ct('controller', OFControllerType, is_list=True),
+    ]
+
+
+class OFLogicalSwitchResourcesType(_Base):
+    _ELEMENTS = [
+        _e('port', is_list=True),
+        _e('queue', is_list=True),
+        _e('certificate', is_list=False),
+        _e('flow-table', is_list=True),
+    ]
+
+
+class OFLogicalSwitchType(_Base):
+    _ELEMENTS = [
+        _e('id', is_list=False),
+        _ct('capabilities', None, is_list=False),
+        _e('datapath-id', is_list=False),
+        _e('enabled', is_list=False),
+        _e('check-controller-certificate', is_list=False),
+        _e('lost-connection-behavior', is_list=False),
+        _ct('controllers', OFLogicalSwitchControllersType, is_list=False),
+        _ct('resources', OFLogicalSwitchResourcesType, is_list=False),
+    ]
+
+
+class OFCapableSwitchLogicalSwitchesType(_Base):
+    _ELEMENTS = [
+        # this is named 'logical-switch' for OF-Config 1.1.
+        _ct('switch', OFLogicalSwitchType, is_list=True),
+    ]
+
+
+class OFCapableSwitchType(_Base):
+    _ELEMENTS = [
+        _e('id', is_list=False),
+        _e('config-version', is_list=False),
+        _ct('configuration-points', None, is_list=False),
+        _ct('resources', OFCapableSwitchResourcesType, is_list=False),
+        _ct('logical-switches', OFCapableSwitchLogicalSwitchesType,
+            is_list=False),
+    ]