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mirror of https://github.com/GNS3/gns3-server synced 2024-12-25 00:08:11 +00:00
gns3-server/gns3server/ubridge/ubridge_hypervisor.py
2016-11-17 18:11:56 +01:00

264 lines
8.0 KiB
Python

# -*- coding: utf-8 -*-
#
# Copyright (C) 2015 GNS3 Technologies Inc.
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
import re
import time
import logging
import asyncio
from ..utils.asyncio import locked_coroutine
from .ubridge_error import UbridgeError
log = logging.getLogger(__name__)
class UBridgeHypervisor:
"""
Creates a new connection to uBridge hypervisor.
:param host: the hostname or ip address string of the uBridge hypervisor
:param port: the tcp port integer
:param timeout: timeout integer for how long to wait for a response to commands sent to the
hypervisor (defaults to 30 seconds)
"""
# Used to parse Ubridge response codes
error_re = re.compile(r"""^2[0-9]{2}-""")
success_re = re.compile(r"""^1[0-9]{2}\s{1}""")
def __init__(self, host, port, timeout=30.0):
self._host = host
self._port = port
self._version = "N/A"
self._timeout = timeout
self._reader = None
self._writer = None
@asyncio.coroutine
def connect(self, timeout=10):
"""
Connects to the hypervisor.
"""
# connect to a local address by default
# if listening to all addresses (IPv4 or IPv6)
if self._host == "0.0.0.0":
host = "127.0.0.1"
elif self._host == "::":
host = "::1"
else:
host = self._host
begin = time.time()
connection_success = False
last_exception = None
while time.time() - begin < timeout:
yield from asyncio.sleep(0.01)
try:
self._reader, self._writer = yield from asyncio.open_connection(host, self._port)
except OSError as e:
last_exception = e
continue
connection_success = True
break
if not connection_success:
raise UbridgeError("Couldn't connect to hypervisor on {}:{} :{}".format(host, self._port, last_exception))
else:
log.info("Connected to uBridge hypervisor after {:.4f} seconds".format(time.time() - begin))
try:
version = yield from self.send("hypervisor version")
self._version = version[0].split("-", 1)[0]
except IndexError:
self._version = "Unknown"
@property
def version(self):
"""
Returns uBridge version.
:returns: version string
"""
return self._version
@asyncio.coroutine
def close(self):
"""
Closes the connection to this hypervisor (but leave it running).
"""
yield from self.send("hypervisor close")
self._writer.close()
self._reader, self._writer = None
@asyncio.coroutine
def stop(self):
"""
Stops this hypervisor (will no longer run).
"""
try:
# try to properly stop the hypervisor
yield from self.send("hypervisor stop")
except UbridgeError:
pass
try:
if self._writer is not None:
yield from self._writer.drain()
self._writer.close()
except OSError as e:
log.debug("Stopping hypervisor {}:{} {}".format(self._host, self._port, e))
self._reader = self._writer = None
@asyncio.coroutine
def reset(self):
"""
Resets this hypervisor (used to get an empty configuration).
"""
yield from self.send("hypervisor reset")
@property
def port(self):
"""
Returns the port used to start the hypervisor.
:returns: port number (integer)
"""
return self._port
@port.setter
def port(self, port):
"""
Sets the port used to start the hypervisor.
:param port: port number (integer)
"""
self._port = port
@property
def host(self):
"""
Returns the host (binding) used to start the hypervisor.
:returns: host/address (string)
"""
return self._host
@host.setter
def host(self, host):
"""
Sets the host (binding) used to start the hypervisor.
:param host: host/address (string)
"""
self._host = host
@locked_coroutine
def send(self, command):
"""
Sends commands to this hypervisor.
:param command: a uBridge hypervisor command
:returns: results as a list
"""
# uBridge responses are of the form:
# 1xx yyyyyy\r\n
# 1xx yyyyyy\r\n
# ...
# 100-yyyy\r\n
# or
# 2xx-yyyy\r\n
#
# Where 1xx is a code from 100-199 for a success or 200-299 for an error
# The result might be multiple lines and might be less than the buffer size
# but still have more data. The only thing we know for sure is the last line
# will begin with '100-' or a '2xx-' and end with '\r\n'
if self._writer is None or self._reader is None:
raise UbridgeError("Not connected")
try:
command = command.strip() + '\n'
log.debug("sending {}".format(command))
self._writer.write(command.encode())
yield from self._writer.drain()
except OSError as e:
raise UbridgeError("Lost communication with {host}:{port} :{error}, Dynamips process running: {run}"
.format(host=self._host, port=self._port, error=e, run=self.is_running()))
# Now retrieve the result
data = []
buf = ''
while True:
try:
try:
chunk = yield from self._reader.read(1024)
except asyncio.CancelledError:
# task has been canceled but continue to read
# any remaining data sent by the hypervisor
continue
if not chunk:
raise UbridgeError("No data returned from {host}:{port}, uBridge process running: {run}"
.format(host=self._host, port=self._port, run=self.is_running()))
buf += chunk.decode("utf-8")
except OSError as e:
raise UbridgeError("Lost communication with {host}:{port} :{error}, uBridge process running: {run}"
.format(host=self._host, port=self._port, error=e, run=self.is_running()))
# If the buffer doesn't end in '\n' then we can't be done
try:
if buf[-1] != '\n':
continue
except IndexError:
raise UbridgeError("Could not communicate with {host}:{port}, uBridge process running: {run}"
.format(host=self._host, port=self._port, run=self.is_running()))
data += buf.split('\r\n')
if data[-1] == '':
data.pop()
buf = ''
# Does it contain an error code?
if self.error_re.search(data[-1]):
raise UbridgeError(data[-1][4:])
# Or does the last line begin with '100-'? Then we are done!
if data[-1][:4] == '100-':
data[-1] = data[-1][4:]
if data[-1] == 'OK':
data.pop()
break
# Remove success responses codes
for index in range(len(data)):
if self.success_re.search(data[index]):
data[index] = data[index][4:]
log.debug("returned result {}".format(data))
return data