-import asyncio
+import base64
+import io
import json
import logging
+import os
import random
+import shlex
import ssl
import string
+import subprocess
import websockets
+from http.client import HTTPSConnection
+
+import asyncio
+import yaml
+from juju import tag
+from juju.errors import JujuError, JujuAPIError, JujuConnectionError
+from juju.utils import IdQueue
log = logging.getLogger("websocket")
+
+class Monitor:
+ """
+ Monitor helper class for our Connection class.
+
+ Contains a reference to an instantiated Connection, along with a
+ reference to the Connection.receiver Future. Upon inspecttion of
+ these objects, this class determines whether the connection is in
+ an 'error', 'connected' or 'disconnected' state.
+
+ Use this class to stay up to date on the health of a connection,
+ and take appropriate action if the connection errors out due to
+ network issues or other unexpected circumstances.
+
+ """
+ ERROR = 'error'
+ CONNECTED = 'connected'
+ DISCONNECTED = 'disconnected'
+ UNKNOWN = 'unknown'
+
+ def __init__(self, connection):
+ self.connection = connection
+ self.receiver = None
+
+ @property
+ def status(self):
+ """
+ Determine the status of the connection and receiver, and return
+ ERROR, CONNECTED, or DISCONNECTED as appropriate.
+
+ For simplicity, we only consider ourselves to be connected
+ after the Connection class has setup a receiver task. This
+ only happens after the websocket is open, and the connection
+ isn't usable until that receiver has been started.
+
+ """
+
+ # DISCONNECTED: connection not yet open
+ if not self.connection.ws:
+ return self.DISCONNECTED
+ if not self.receiver:
+ return self.DISCONNECTED
+
+ # ERROR: Connection closed (or errored), but we didn't call
+ # connection.close
+ if not self.connection.close_called and self.receiver_exceptions():
+ return self.ERROR
+ if not self.connection.close_called and not self.connection.ws.open:
+ # The check for self.receiver existing above guards against the
+ # case where we're not open because we simply haven't
+ # setup the connection yet.
+ return self.ERROR
+
+ # DISCONNECTED: cleanly disconnected.
+ if self.connection.close_called and not self.connection.ws.open:
+ return self.DISCONNECTED
+
+ # CONNECTED: everything is fine!
+ if self.connection.ws.open:
+ return self.CONNECTED
+
+ # UNKNOWN: We should never hit this state -- if we do,
+ # something went wrong with the logic above, and we do not
+ # know what state the connection is in.
+ return self.UNKNOWN
+
+ def receiver_exceptions(self):
+ """
+ Return exceptions in the receiver, if any.
+
+ """
+ if not self.receiver:
+ return None
+ if not self.receiver.done():
+ return None
+ return self.receiver.exception()
+
+
class Connection:
"""
- Usage:
- client = await Connection.connect(info)
+ Usage::
+
+ # Connect to an arbitrary api server
+ client = await Connection.connect(
+ api_endpoint, model_uuid, username, password, cacert)
+
+ # Connect using a controller/model name
+ client = await Connection.connect_model('local.local:default')
+
+ # Connect to the currently active model
+ client = await Connection.connect_current()
+
+ Note: Any connection method or constructor can accept an optional `loop`
+ argument to override the default event loop from `asyncio.get_event_loop`.
"""
- def __init__(self):
- self.__requestId__ = 0
+ def __init__(
+ self, endpoint, uuid, username, password, cacert=None,
+ macaroons=None, loop=None):
+ self.endpoint = endpoint
+ self.uuid = uuid
+ self.username = username
+ self.password = password
+ self.macaroons = macaroons
+ self.cacert = cacert
+ self.loop = loop or asyncio.get_event_loop()
+
+ self.__request_id__ = 0
self.addr = None
self.ws = None
+ self.facades = {}
+ self.messages = IdQueue(loop=self.loop)
+ self.close_called = False
+ self.monitor = Monitor(connection=self)
+
+ @property
+ def is_open(self):
+ if self.ws:
+ return self.ws.open
+ return False
- def _get_ssl(self, cert):
+ def _get_ssl(self, cert=None):
return ssl.create_default_context(
purpose=ssl.Purpose.CLIENT_AUTH, cadata=cert)
- async def open(self, addr, cert=None):
+ async def open(self):
+ if self.uuid:
+ url = "wss://{}/model/{}/api".format(self.endpoint, self.uuid)
+ else:
+ url = "wss://{}/api".format(self.endpoint)
+
kw = dict()
- if cert:
- kw['ssl'] = self._get_ssl(cert)
- self.addr = addr
- self.ws = await websockets.connect(addr, **kw)
+ kw['ssl'] = self._get_ssl(self.cacert)
+ kw['loop'] = self.loop
+ self.addr = url
+ self.ws = await websockets.connect(url, **kw)
+ self.monitor.receiver = self.loop.create_task(self.receiver())
+ log.info("Driver connected to juju %s", url)
return self
async def close(self):
+ self.close_called = True
await self.ws.close()
- async def recv(self):
- result = await self.ws.recv()
- if result is not None:
- result = json.loads(result)
- return result
+ async def recv(self, request_id):
+ if not self.is_open:
+ raise websockets.exceptions.ConnectionClosed(0, 'websocket closed')
+ return await self.messages.get(request_id)
+
+ async def receiver(self):
+ while self.is_open:
+ try:
+ result = await self.ws.recv()
+ if result is not None:
+ result = json.loads(result)
+ await self.messages.put(result['request-id'], result)
+ except Exception as e:
+ await self.messages.put_all(e)
+ if isinstance(e, websockets.ConnectionClosed):
+ # ConnectionClosed is not really exceptional for us,
+ # but it may be for any pending message listeners
+ return
+ raise
- async def rpc(self, msg):
- self.__requestID += 1
- msg['RequestId'] = self.__requestID
- if'Params' not in msg:
- msg['Params'] = {}
- if "Version" not in msg:
- msg['Version'] = self.facades[msg['Type']]
- outgoing = json.dumps(msg, indent=2)
+ async def rpc(self, msg, encoder=None):
+ self.__request_id__ += 1
+ msg['request-id'] = self.__request_id__
+ if'params' not in msg:
+ msg['params'] = {}
+ if "version" not in msg:
+ msg['version'] = self.facades[msg['type']]
+ outgoing = json.dumps(msg, indent=2, cls=encoder)
await self.ws.send(outgoing)
- result = await self.recv()
- log.debug("send %s got %s", msg, result)
- if result and 'Error' in result:
- raise RuntimeError(result)
+ result = await self.recv(msg['request-id'])
+
+ if not result:
+ return result
+
+ if 'error' in result:
+ # API Error Response
+ raise JujuAPIError(result)
+
+ if 'response' not in result:
+ # This may never happen
+ return result
+
+ if 'results' in result['response']:
+ # Check for errors in a result list.
+ errors = []
+ for res in result['response']['results']:
+ if res.get('error', {}).get('message'):
+ errors.append(res['error']['message'])
+ if errors:
+ raise JujuError(errors)
+
+ elif result['response'].get('error', {}).get('message'):
+ raise JujuError(result['response']['error']['message'])
+
return result
+ def http_headers(self):
+ """Return dictionary of http headers necessary for making an http
+ connection to the endpoint of this Connection.
+
+ :return: Dictionary of headers
+
+ """
+ if not self.username:
+ return {}
+
+ creds = u'{}:{}'.format(
+ tag.user(self.username),
+ self.password or ''
+ )
+ token = base64.b64encode(creds.encode())
+ return {
+ 'Authorization': 'Basic {}'.format(token.decode())
+ }
+
+ def https_connection(self):
+ """Return an https connection to this Connection's endpoint.
+
+ Returns a 3-tuple containing::
+
+ 1. The :class:`HTTPSConnection` instance
+ 2. Dictionary of auth headers to be used with the connection
+ 3. The root url path (str) to be used for requests.
+
+ """
+ endpoint = self.endpoint
+ host, remainder = endpoint.split(':', 1)
+ port = remainder
+ if '/' in remainder:
+ port, _ = remainder.split('/', 1)
+
+ conn = HTTPSConnection(
+ host, int(port),
+ context=self._get_ssl(self.cacert),
+ )
+
+ path = (
+ "/model/{}".format(self.uuid)
+ if self.uuid else ""
+ )
+ return conn, self.http_headers(), path
+
+ async def clone(self):
+ """Return a new Connection, connected to the same websocket endpoint
+ as this one.
+
+ """
+ return await Connection.connect(
+ self.endpoint,
+ self.uuid,
+ self.username,
+ self.password,
+ self.cacert,
+ self.macaroons,
+ self.loop,
+ )
+
+ async def controller(self):
+ """Return a Connection to the controller at self.endpoint
+
+ """
+ return await Connection.connect(
+ self.endpoint,
+ None,
+ self.username,
+ self.password,
+ self.cacert,
+ self.macaroons,
+ self.loop,
+ )
+
+ @classmethod
+ async def connect(
+ cls, endpoint, uuid, username, password, cacert=None,
+ macaroons=None, loop=None):
+ """Connect to the websocket.
+
+ If uuid is None, the connection will be to the controller. Otherwise it
+ will be to the model.
+
+ """
+ client = cls(endpoint, uuid, username, password, cacert, macaroons,
+ loop)
+ await client.open()
+
+ redirect_info = await client.redirect_info()
+ if not redirect_info:
+ await client.login(username, password, macaroons)
+ return client
+
+ await client.close()
+ servers = [
+ s for servers in redirect_info['servers']
+ for s in servers if s["scope"] == 'public'
+ ]
+ for server in servers:
+ client = cls(
+ "{value}:{port}".format(**server), uuid, username,
+ password, redirect_info['ca-cert'], macaroons)
+ await client.open()
+ try:
+ result = await client.login(username, password, macaroons)
+ if 'discharge-required-error' in result:
+ continue
+ return client
+ except Exception as e:
+ await client.close()
+ log.exception(e)
+
+ raise Exception(
+ "Couldn't authenticate to %s", endpoint)
+
+ @classmethod
+ async def connect_current(cls, loop=None):
+ """Connect to the currently active model.
+
+ """
+ jujudata = JujuData()
+ controller_name = jujudata.current_controller()
+ model_name = jujudata.current_model()
+
+ return await cls.connect_model(
+ '{}:{}'.format(controller_name, model_name), loop)
+
+ @classmethod
+ async def connect_current_controller(cls, loop=None):
+ """Connect to the currently active controller.
+
+ """
+ jujudata = JujuData()
+ controller_name = jujudata.current_controller()
+ if not controller_name:
+ raise JujuConnectionError('No current controller')
+
+ return await cls.connect_controller(controller_name, loop)
+
+ @classmethod
+ async def connect_controller(cls, controller_name, loop=None):
+ """Connect to a controller by name.
+
+ """
+ jujudata = JujuData()
+ controller = jujudata.controllers()[controller_name]
+ endpoint = controller['api-endpoints'][0]
+ cacert = controller.get('ca-cert')
+ accounts = jujudata.accounts()[controller_name]
+ username = accounts['user']
+ password = accounts.get('password')
+ macaroons = get_macaroons() if not password else None
+
+ return await cls.connect(
+ endpoint, None, username, password, cacert, macaroons, loop)
+
@classmethod
- async def connect(cls, info):
- uuid = info.model_uuid
- controller = info.controller
- details = controller['details']
- endpoint = "wss://{}/model/{}/api".format(
- details['api-endpoints'][0],
- entity.model_uuid)
- client = cls()
- await client.dial(endpoint, details['ca-cert'])
- server_info = await client.login(info)
- client.build_facades(server_info['facades'])
- log.info("Driver connected to juju %s", endpoint)
- return client
+ async def connect_model(cls, model, loop=None):
+ """Connect to a model by name.
+
+ :param str model: [<controller>:]<model>
+
+ """
+ jujudata = JujuData()
+
+ if ':' in model:
+ # explicit controller given
+ controller_name, model_name = model.split(':')
+ else:
+ # use the current controller if one isn't explicitly given
+ controller_name = jujudata.current_controller()
+ model_name = model
+
+ accounts = jujudata.accounts()[controller_name]
+ username = accounts['user']
+ # model name must include a user prefix, so add it if it doesn't
+ if '/' not in model_name:
+ model_name = '{}/{}'.format(username, model_name)
+
+ controller = jujudata.controllers()[controller_name]
+ endpoint = controller['api-endpoints'][0]
+ cacert = controller.get('ca-cert')
+ password = accounts.get('password')
+ models = jujudata.models()[controller_name]
+ model_uuid = models['models'][model_name]['uuid']
+ macaroons = get_macaroons() if not password else None
+
+ return await cls.connect(
+ endpoint, model_uuid, username, password, cacert, macaroons, loop)
def build_facades(self, info):
self.facades.clear()
for facade in info:
- self.facades[facade['Name']] = facade['Versions'][-1]
-
- async def login(self, info):
- account = info.account
- result = await client.rpc({
- "Type": "Admin",
- "Request": "Login",
- "Version": 3,
- "Params": {
- "auth-tag": "user-{}".format(account['user']),
- "credentials": account['password'],
- "Nonce": "".join(random.sample(string.printable, 12)),
+ self.facades[facade['name']] = facade['versions'][-1]
+
+ async def login(self, username, password, macaroons=None):
+ if macaroons:
+ username = ''
+ password = ''
+
+ if username and not username.startswith('user-'):
+ username = 'user-{}'.format(username)
+
+ result = await self.rpc({
+ "type": "Admin",
+ "request": "Login",
+ "version": 3,
+ "params": {
+ "auth-tag": username,
+ "credentials": password,
+ "nonce": "".join(random.sample(string.printable, 12)),
+ "macaroons": macaroons or []
}})
- return result['Response']
+ response = result['response']
+ self.build_facades(response.get('facades', {}))
+ self.info = response.copy()
+ return response
+
+ async def redirect_info(self):
+ try:
+ result = await self.rpc({
+ "type": "Admin",
+ "request": "RedirectInfo",
+ "version": 3,
+ })
+ except JujuAPIError as e:
+ if e.message == 'not redirected':
+ return None
+ raise
+ return result['response']
+
+
+class JujuData:
+ def __init__(self):
+ self.path = os.environ.get('JUJU_DATA') or '~/.local/share/juju'
+ self.path = os.path.abspath(os.path.expanduser(self.path))
+
+ def current_controller(self):
+ cmd = shlex.split('juju list-controllers --format yaml')
+ output = subprocess.check_output(cmd)
+ output = yaml.safe_load(output)
+ return output.get('current-controller', '')
+
+ def current_model(self, controller_name=None):
+ if not controller_name:
+ controller_name = self.current_controller()
+ models = self.models()[controller_name]
+ if 'current-model' not in models:
+ raise JujuError('No current model')
+ return models['current-model']
+
+ def controllers(self):
+ return self._load_yaml('controllers.yaml', 'controllers')
+
+ def models(self):
+ return self._load_yaml('models.yaml', 'controllers')
+
+ def accounts(self):
+ return self._load_yaml('accounts.yaml', 'controllers')
+
+ def _load_yaml(self, filename, key):
+ filepath = os.path.join(self.path, filename)
+ with io.open(filepath, 'rt') as f:
+ return yaml.safe_load(f)[key]
+
+
+def get_macaroons():
+ """Decode and return macaroons from default ~/.go-cookies
+
+ """
+ try:
+ cookie_file = os.path.expanduser('~/.go-cookies')
+ with open(cookie_file, 'r') as f:
+ cookies = json.load(f)
+ except (OSError, ValueError):
+ log.warn("Couldn't load macaroons from %s", cookie_file)
+ return []
+ base64_macaroons = [
+ c['Value'] for c in cookies
+ if c['Name'].startswith('macaroon-') and c['Value']
+ ]
+ return [
+ json.loads(base64.b64decode(value).decode('utf-8'))
+ for value in base64_macaroons
+ ]