Initial commit

[ta/lockcli.git] / src / lockcli / handlers.py

diff --git a/src/lockcli/handlers.py b/src/lockcli/handlers.py
new file mode 100644 (file)
index 0000000..efc911c
--- /dev/null
+++ b/src/lockcli/handlers.py
@@ -0,0 +1,127 @@
+# Copyright 2019 Nokia
+
+# 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.
+
+from __future__ import print_function
+import sys
+import inspect
+import etcd
+
+
+class VerboseLogger(object):
+    def __call__(self, msg):
+        print(msg)
+
+
+class CLIHandler(object):
+    def __init__(self):
+        self.sock = None
+        self.verbose_logger = VerboseLogger()
+        self.client = None
+
+    def _init_api(self, server, port, verbose):
+        logger = None
+        if verbose:
+            logger = self.verbose_logger
+
+        if server == 'none':
+            import socket
+            server = socket.gethostname()
+
+        self.client = etcd.Client(server, port)
+
+    def set_handler(self, subparser):
+        subparser.set_defaults(handler=self)
+
+    def init_subparser(self, subparsers):
+        raise Error('Not implemented')
+
+    def __call__(self, args):
+        raise Error('Not implemented')
+
+
+class CLILockHandler(CLIHandler):
+    def init_subparser(self, subparsers):
+        subparser = subparsers.add_parser('lock', help='Acquire a lock')
+        subparser.add_argument('--id',
+                               required=True,
+                               dest='id',
+                               metavar='ID',
+                               type=str,
+                               action='store')
+
+        subparser.add_argument('--timeout',
+                               required=True,
+                               dest='timeout',
+                               metavar='TIMEOUT',
+                               type=int,
+                               action='store')
+
+        self.set_handler(subparser)
+
+    def __call__(self, args):
+        self._init_api(args.server, args.port, args.verbose)
+        lock = etcd.Lock(self.client, args.id)
+        result = lock.acquire(blocking=False, lock_ttl=args.timeout)
+        if not result:
+            raise Exception('Lock taken!')
+
+        print('Lock acquired successfully!')
+        print('uuid=%s' % lock.uuid)
+
+class CLIUnlockHandler(CLIHandler):
+    def init_subparser(self, subparsers):
+        subparser = subparsers.add_parser('unlock', help='Release a lock')
+        subparser.add_argument('--id',
+                               required=True,
+                               dest='id',
+                               metavar='ID',
+                               type=str,
+                               action='store')
+
+        subparser.add_argument('--uuid',
+                               required=True,
+                               dest='uuid',
+                               metavar='UUID',
+                               type=str,
+                               action='store')
+        self.set_handler(subparser)
+
+    def __call__(self, args):
+        self._init_api(args.server, args.port, args.verbose)
+        lock = etcd.Lock(self.client, args.id)
+        try:
+            lock._uuid = args.uuid
+            lock.release()
+            print('Lock released successfully!')
+        except ValueError:
+            print('Lock is not held!')
+
+def get_handlers_list():
+    handlers = []
+    for name, obj in inspect.getmembers(sys.modules[__name__]):
+        if inspect.isclass(obj):
+            if name is not 'CLIHandler':
+                if issubclass(obj, CLIHandler):
+                    handlers.append(obj())
+    return handlers
+
+
+def main():
+    handlers = get_handlers_list()
+    for handler in handlers:
+        print('handler is ', handler)
+
+
+if __name__ == '__main__':
+    main()