2
0
mirror of https://github.com/openvswitch/ovs synced 2025-10-23 14:57:06 +00:00
Files
openvswitch/python/ovs/unixctl.py
Ethan Jackson c9a2d670eb python: Make build number format consistent with C.
The C code displays the build number as the empty string when 0,
and as +build<num> otherwise.  This commit updates version.py to be
consistent and tests that it is in the unit tests.

Signed-off-by: Ethan Jackson <ethan@nicira.com>
2012-03-07 16:50:16 -08:00

307 lines
9.5 KiB
Python

# Copyright (c) 2012 Nicira Networks
#
# 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
import errno
import os
import types
import ovs.daemon
import ovs.dirs
import ovs.jsonrpc
import ovs.stream
import ovs.util
import ovs.version
import ovs.vlog
Message = ovs.jsonrpc.Message
vlog = ovs.vlog.Vlog("unixctl")
commands = {}
strtypes = types.StringTypes
class _UnixctlCommand(object):
def __init__(self, usage, min_args, max_args, callback, aux):
self.usage = usage
self.min_args = min_args
self.max_args = max_args
self.callback = callback
self.aux = aux
def _unixctl_help(conn, unused_argv, unused_aux):
assert isinstance(conn, UnixctlConnection)
reply = "The available commands are:\n"
command_names = sorted(commands.keys())
for name in command_names:
reply += " "
usage = commands[name].usage
if usage:
reply += "%-23s %s" % (name, usage)
else:
reply += name
reply += "\n"
conn.reply(reply)
def _unixctl_version(conn, unused_argv, unused_aux):
assert isinstance(conn, UnixctlConnection)
version = "%s (Open vSwitch) %s%s" % (ovs.util.PROGRAM_NAME,
ovs.version.VERSION,
ovs.version.BUILDNR)
conn.reply(version)
def command_register(name, usage, min_args, max_args, callback, aux):
""" Registers a command with the given 'name' to be exposed by the
UnixctlServer. 'usage' describes the arguments to the command; it is used
only for presentation to the user in "help" output.
'callback' is called when the command is received. It is passed a
UnixctlConnection object, the list of arguments as unicode strings, and
'aux'. Normally 'callback' should reply by calling
UnixctlConnection.reply() or UnixctlConnection.reply_error() before it
returns, but if the command cannot be handled immediately, then it can
defer the reply until later. A given connection can only process a single
request at a time, so a reply must be made eventually to avoid blocking
that connection."""
assert isinstance(name, strtypes)
assert isinstance(usage, strtypes)
assert isinstance(min_args, int)
assert isinstance(max_args, int)
assert isinstance(callback, types.FunctionType)
if name not in commands:
commands[name] = _UnixctlCommand(usage, min_args, max_args, callback,
aux)
def socket_name_from_target(target):
assert isinstance(target, strtypes)
if target.startswith("/"):
return 0, target
pidfile_name = "%s/%s.pid" % (ovs.dirs.RUNDIR, target)
pid = ovs.daemon.read_pidfile(pidfile_name)
if pid < 0:
return -pid, "cannot read pidfile \"%s\"" % pidfile_name
return 0, "%s/%s.%d.ctl" % (ovs.dirs.RUNDIR, target, pid)
class UnixctlConnection(object):
def __init__(self, rpc):
assert isinstance(rpc, ovs.jsonrpc.Connection)
self._rpc = rpc
self._request_id = None
def run(self):
self._rpc.run()
error = self._rpc.get_status()
if error or self._rpc.get_backlog():
return error
for _ in range(10):
if error or self._request_id:
break
error, msg = self._rpc.recv()
if msg:
if msg.type == Message.T_REQUEST:
self._process_command(msg)
else:
# XXX: rate-limit
vlog.warn("%s: received unexpected %s message"
% (self._rpc.name,
Message.type_to_string(msg.type)))
error = errno.EINVAL
if not error:
error = self._rpc.get_status()
return error
def reply(self, body):
self._reply_impl(True, body)
def reply_error(self, body):
self._reply_impl(False, body)
# Called only by unixctl classes.
def _close(self):
self._rpc.close()
self._request_id = None
def _wait(self, poller):
self._rpc.wait(poller)
if not self._rpc.get_backlog():
self._rpc.recv_wait(poller)
def _reply_impl(self, success, body):
assert isinstance(success, bool)
assert body is None or isinstance(body, strtypes)
assert self._request_id is not None
if body is None:
body = ""
if body and not body.endswith("\n"):
body += "\n"
if success:
reply = Message.create_reply(body, self._request_id)
else:
reply = Message.create_error(body, self._request_id)
self._rpc.send(reply)
self._request_id = None
def _process_command(self, request):
assert isinstance(request, ovs.jsonrpc.Message)
assert request.type == ovs.jsonrpc.Message.T_REQUEST
self._request_id = request.id
error = None
params = request.params
method = request.method
command = commands.get(method)
if command is None:
error = '"%s" is not a valid command' % method
elif len(params) < command.min_args:
error = '"%s" command requires at least %d arguments' \
% (method, command.min_args)
elif len(params) > command.max_args:
error = '"%s" command takes at most %d arguments' \
% (method, command.max_args)
else:
for param in params:
if not isinstance(param, strtypes):
error = '"%s" command has non-string argument' % method
break
if error is None:
unicode_params = [unicode(p) for p in params]
command.callback(self, unicode_params, command.aux)
if error:
self.reply_error(error)
class UnixctlServer(object):
def __init__(self, listener):
assert isinstance(listener, ovs.stream.PassiveStream)
self._listener = listener
self._conns = []
def run(self):
for _ in range(10):
error, stream = self._listener.accept()
if not error:
rpc = ovs.jsonrpc.Connection(stream)
self._conns.append(UnixctlConnection(rpc))
elif error == errno.EAGAIN:
break
else:
# XXX: rate-limit
vlog.warn("%s: accept failed: %s" % (self._listener.name,
os.strerror(error)))
for conn in copy.copy(self._conns):
error = conn.run()
if error and error != errno.EAGAIN:
conn._close()
self._conns.remove(conn)
def wait(self, poller):
self._listener.wait(poller)
for conn in self._conns:
conn._wait(poller)
def close(self):
for conn in self._conns:
conn._close()
self._conns = None
self._listener.close()
self._listener = None
@staticmethod
def create(path):
assert path is None or isinstance(path, strtypes)
if path is not None:
path = "punix:%s" % ovs.util.abs_file_name(ovs.dirs.RUNDIR, path)
else:
path = "punix:%s/%s.%d.ctl" % (ovs.dirs.RUNDIR,
ovs.util.PROGRAM_NAME, os.getpid())
error, listener = ovs.stream.PassiveStream.open(path)
if error:
ovs.util.ovs_error(error, "could not initialize control socket %s"
% path)
return error, None
command_register("help", "", 0, 0, _unixctl_help, None)
command_register("version", "", 0, 0, _unixctl_version, None)
return 0, UnixctlServer(listener)
class UnixctlClient(object):
def __init__(self, conn):
assert isinstance(conn, ovs.jsonrpc.Connection)
self._conn = conn
def transact(self, command, argv):
assert isinstance(command, strtypes)
assert isinstance(argv, list)
for arg in argv:
assert isinstance(arg, strtypes)
request = Message.create_request(command, argv)
error, reply = self._conn.transact_block(request)
if error:
vlog.warn("error communicating with %s: %s"
% (self._conn.name, os.strerror(error)))
return error, None, None
if reply.error is not None:
return 0, str(reply.error), None
else:
assert reply.result is not None
return 0, None, str(reply.result)
def close(self):
self._conn.close()
self.conn = None
@staticmethod
def create(path):
assert isinstance(path, str)
unix = "unix:%s" % ovs.util.abs_file_name(ovs.dirs.RUNDIR, path)
error, stream = ovs.stream.Stream.open_block(
ovs.stream.Stream.open(unix))
if error:
vlog.warn("failed to connect to %s" % path)
return error, None
return 0, UnixctlClient(ovs.jsonrpc.Connection(stream))