logger = logging.getLogger("ncclient.operations.rpc")
+class RPCError(OperationError):
+
+ "Represents an `rpc-error`. It is a type of :exc:`OperationError` and can be raised as such."
+
+ tag_to_attr = {
+ qualify("error-type"): "_type",
+ qualify("error-tag"): "_tag",
+ qualify("error-severity"): "_severity",
+ qualify("error-info"): "_info",
+ qualify("error-path"): "_path",
+ qualify("error-message"): "_message"
+ }
+
+ def __init__(self, raw):
+ self._raw = raw
+ for attr in RPCError.tag_to_attr.values():
+ setattr(self, attr, None)
+ for subele in raw:
+ attr = RPCError.tag_to_attr.get(subele.tag, None)
+ if attr is not None:
+ setattr(self, attr, subele.text if attr != "_info" else to_xml(subele) )
+ if self.message is not None:
+ OperationError.__init__(self, self.message)
+ else:
+ OperationError.__init__(self, self.to_dict())
+
+ def to_dict(self):
+ return dict([ (attr[1:], getattr(self, attr)) for attr in RPCError.tag_to_attr.values() ])
+
+ @property
+ def xml(self):
+ "The `rpc-error` element as returned in XML."
+ return self._raw
+
+ @property
+ def type(self):
+ "The contents of the `error-type` element."
+ return self._type
+
+ @property
+ def tag(self):
+ "The contents of the `error-tag` element."
+ return self._tag
+
+ @property
+ def severity(self):
+ "The contents of the `error-severity` element."
+ return self._severity
+
+ @property
+ def path(self):
+ "The contents of the `error-path` element if present or `None`."
+ return self._path
+
+ @property
+ def message(self):
+ "The contents of the `error-message` element if present or `None`."
+ return self._message
+
+ @property
+ def info(self):
+ "XML string or `None`; representing the `error-info` element."
+ return self._info
+
+
class RPCReply:
- """Represents an *<rpc-reply>*. Only concerns itself with whether the
- operation was successful.
+ """Represents an *rpc-reply*. Only concerns itself with whether the operation was successful.
.. note::
- If the reply has not yet been parsed there is an implicit, one-time
- parsing overhead to accessing the attributes defined by this class and
- any subclasses.
+ If the reply has not yet been parsed there is an implicit, one-time parsing overhead to
+ accessing some of the attributes defined by this class.
"""
-
+
+ ERROR_CLS = RPCError
+ "Subclasses can specify a different error class, but it should be a subclass of `RPCError`."
+
def __init__(self, raw):
self._raw = raw
self._parsed = False
def __repr__(self):
return self._raw
-
- def _parsing_hook(self, root):
- """Subclass can implement.
-
- :type root: :class:`~xml.etree.ElementTree.Element`
- """
- pass
-
+
def parse(self):
- """Parse the *<rpc-reply>*"""
- if self._parsed:
- return
+ "Parses the *rpc-reply*."
+ if self._parsed: return
root = self._root = to_ele(self._raw) # The <rpc-reply> element
# Per RFC 4741 an <ok/> tag is sent when there are no errors or warnings
ok = root.find(qualify("ok"))
if error is not None:
for err in root.getiterator(error.tag):
# Process a particular <rpc-error>
- self._errors.append(RPCError(err))
+ self._errors.append(self.ERROR_CLS(err))
self._parsing_hook(root)
self._parsed = True
+ def _parsing_hook(self, root):
+ "No-op by default. Gets passed the *root* element for the reply."
+ pass
+
@property
def xml(self):
- "*<rpc-reply>* as returned"
+ "*rpc-reply* element as returned."
return self._raw
-
+
@property
def ok(self):
"Boolean value indicating if there were no errors."
- if not self._parsed:
- self.parse()
- return not self._errors # empty list => false
-
+ return not self.errors # empty list => false
+
@property
def error(self):
- """Short for :attr:`errors` [0]; :const:`None` if there were no errors.
- """
- if not self._parsed:
- self.parse()
+ "Returns the first :class:`RPCError` and `None` if there were no errors."
+ self.parse()
if self._errors:
return self._errors[0]
else:
return None
-
+
@property
def errors(self):
- """`list` of :class:`RPCError` objects. Will be empty if there were no
- *<rpc-error>* elements in reply.
- """
- if not self._parsed:
- self.parse()
+ "List of `RPCError` objects. Will be empty if there were no *rpc-error* elements in reply."
+ self.parse()
return self._errors
-class RPCError(OperationError):
-
- """Represents an *<rpc-error>*. It is a type of :exc:`OperationError`
- and can be raised like any other exception."""
-
- def __init__(self, err):
- self._type = None
- self._severity = None
- self._info = None
- self._tag = None
- self._path = None
- self._message = None
- for subele in err:
- if subele.tag == qualify("error-type"):
- self._type = subele.text
- elif subele.tag == qualify("error-tag"):
- self._tag = subele.text
- elif subele.tag == qualify("error-severity"):
- self._severity = subele.text
- elif subele.tag == qualify("error-info"):
- self._info = subele.text
- elif subele.tag == qualify("error-path"):
- self._path = subele.text
- elif subele.tag == qualify("error-message"):
- self._message = subele.text
- if self.message is not None:
- OperationError.__init__(self, self.message)
- else:
- OperationError.__init__(self, to_dict())
+class RPCReplyListener(SessionListener): # internal use
- def to_dict(self):
- return {
- 'type': self.type,
- 'tag': self.severity,
- 'path': self.path,
- 'message': self.message,
- 'info': self.info
- }
+ creation_lock = Lock()
- @property
- def type(self):
- "`string` representing text of *error-type* element"
- return self._type
-
- @property
- def severity(self):
- "`string` representing text of *error-severity* element"
- return self._severity
-
- @property
- def tag(self):
- "`string` representing text of *error-tag* element"
- return self._tag
-
- @property
- def path(self):
- "`string` or :const:`None`; representing text of *error-path* element"
- return self._path
-
- @property
- def message(self):
- "`string` or :const:`None`; representing text of *error-message* element"
- return self._message
-
- @property
- def info(self):
- "`string` (XML) or :const:`None`, representing *error-info* element"
- return self._info
-
-
-class RPCReplyListener(SessionListener):
-
- # internal use
-
# one instance per session -- maybe there is a better way??
def __new__(cls, session):
- instance = session.get_listener_instance(cls)
- if instance is None:
- instance = object.__new__(cls)
- instance._lock = Lock()
- instance._id2rpc = {}
- #instance._pipelined = session.can_pipeline
- session.add_listener(instance)
- return instance
+ with RPCReplyListener.creation_lock:
+ instance = session.get_listener_instance(cls)
+ if instance is None:
+ instance = object.__new__(cls)
+ instance._lock = Lock()
+ instance._id2rpc = {}
+ #instance._pipelined = session.can_pipeline
+ session.add_listener(instance)
+ return instance
def register(self, id, rpc):
with self._lock:
if key == "message-id": # if we found msgid attr
id = attrs[key] # get the msgid
with self._lock:
- try:
+ try:
rpc = self._id2rpc[id] # the corresponding rpc
logger.debug("Delivering to %r" % rpc)
rpc.deliver_reply(raw)
except KeyError:
- raise OperationError("Unknown message-id: %s", id)
+ raise OperationError("Unknown 'message-id': %s", id)
# no catching other exceptions, fail loudly if must
else:
# if no error delivering, can del the reference to the RPC
self._id2rpc.clear()
-class RPC(object):
+class RaiseMode(object):
- """Base class for all operations.
+ NONE = 0
+ "Don't attempt to raise any type of `rpc-error` as :exc:`RPCError`."
- Directly corresponds to *<rpc>* requests. Handles making the request, and
- taking delivery of the reply.
- """
+ ERRORS = 1
+ "Raise only when the `error-type` indicates it is an honest-to-god error."
+
+ ALL = 2
+ "Don't look at the `error-type`, always raise."
- #: Subclasses can specify their dependencies on capabilities. List of URI's
- # or abbreviated names, e.g. ':writable-running'. These are verified at the
- # time of object creation. If the capability is not available, a
- # :exc:`MissingCapabilityError` is raised.
- DEPENDS = []
- #: Subclasses can specify a different reply class, but it must be a
- # subclass of :class:`RPCReply`.
+class RPC(object):
+
+ """Base class for all operations, directly corresponding to *rpc* requests. Handles making the request, and taking delivery of the reply."""
+
+ DEPENDS = []
+ """Subclasses can specify their dependencies on capabilities as a list of URI's or abbreviated names, e.g. ':writable-running'. These are verified at the time of instantiation. If the capability is not available, :exc:`MissingCapabilityError` is raised."""
+
REPLY_CLS = RPCReply
+ "By default :class:`RPCReply`. Subclasses can specify a :class:`RPCReply` subclass."
+
+ def __init__(self, session, async=False, timeout=30, raise_mode=RaiseMode.NONE):
+ """
+ *session* is the :class:`~ncclient.transport.Session` instance
+
+ *async* specifies whether the request is to be made asynchronously, see :attr:`is_async`
- def __init__(self, session, async=False, timeout=None, raise_mode="none"):
+ *timeout* is the timeout for a synchronous request, see :attr:`timeout`
+
+ *raise_mode* specifies the exception raising mode, see :attr:`raise_mode`
+ """
self._session = session
try:
for cap in self.DEPENDS:
self._async = async
self._timeout = timeout
self._raise_mode = raise_mode
- self._id = uuid1().urn # Keeps things simple instead of having a class attr that has to be locked
+ self._id = uuid1().urn # Keeps things simple instead of having a class attr with running ID that has to be locked
self._listener = RPCReplyListener(session)
self._listener.register(self._id, self)
self._reply = None
self._error = None
self._event = Event()
-
- def _build(self, subele):
- # internal
+
+ def _wrap(self, subele):
+ # internal use
ele = new_ele("rpc", {"message-id": self._id}, xmlns=BASE_NS_1_0)
ele.append(subele)
return to_xml(ele)
def _request(self, op):
- """Subclasses call this method to make the RPC request.
+ """Implementations of :meth:`request` call this method to send the request and process the reply.
- In synchronous mode, waits until the reply is received and returns
- :class:`RPCReply`.
+ In synchronous mode, blocks until the reply is received and returns :class:`RPCReply`. Depending on the :attr:`raise_mode` a `rpc-error` element in the reply may lead to an :exc:`RPCError` exception.
- In asynchronous mode, returns immediately, returning a reference to this
- object. The :attr:`event` attribute will be set when the reply has been
- received (see :attr:`reply`) or an error occured (see :attr:`error`).
+ In asynchronous mode, returns immediately, returning `self`. The :attr:`event` attribute will be set when the reply has been received (see :attr:`reply`) or an error occured (see :attr:`error`).
- :type opspec: :obj:`dict` or :obj:`string` or :class:`~xml.etree.ElementTree.Element`
- :rtype: :class:`RPCReply` (sync) or :class:`RPC` (async)
+ *op* is the operation to be requested as an :class:`~xml.etree.ElementTree.Element`
"""
logger.info('Requesting %r' % self.__class__.__name__)
- req = self._build(op)
+ req = self._wrap(op)
self._session.send(req)
if self._async:
logger.debug('Async request, returning %r', self)
return self
else:
- logger.debug('Sync request, will wait for timeout=%r' %
- self._timeout)
+ logger.debug('Sync request, will wait for timeout=%r' % self._timeout)
self._event.wait(self._timeout)
if self._event.isSet():
if self._error:
self._reply.parse()
if self._reply.error is not None:
# <rpc-error>'s [ RPCError ]
- if self._raise_mode == "all":
+ if self._raise_mode == RaiseMode.ALL:
raise self._reply.error
- elif (self._raise_mode == "errors" and
- self._reply.error.type == "error"):
+ elif (self._raise_mode == RaiseMode.ERRORS and self._reply.error.type == "error"):
raise self._reply.error
return self._reply
else:
raise TimeoutExpiredError
- def request(self, *args, **kwds):
- "Subclasses implement this method."
- return self._request(self.SPEC)
+ def request(self):
+ """Subclasses must implement this method. Typically only the request needs to be built as an
+ :class:`~xml.etree.ElementTree.Element` and everything else can be handed off to
+ :meth:`_request`."""
+ pass
def _assert(self, capability):
- """Subclasses can use this method to verify that a capability is available
- with the NETCONF server, before making a request that requires it. A
- :exc:`MissingCapabilityError` will be raised if the capability is not
- available."""
+ """Subclasses can use this method to verify that a capability is available with the NETCONF
+ server, before making a request that requires it. A :exc:`MissingCapabilityError` will be
+ raised if the capability is not available."""
if capability not in self._session.server_capabilities:
- raise MissingCapabilityError('Server does not support [%s]' %
- capability)
+ raise MissingCapabilityError('Server does not support [%s]' % capability)
def deliver_reply(self, raw):
# internal use
# internal use
self._error = err
self._event.set()
-
+
@property
def reply(self):
- ":class:`RPCReply` element if reply has been received or :const:`None`"
+ ":class:`RPCReply` element if reply has been received or `None`"
return self._reply
-
+
@property
def error(self):
- """:exc:`Exception` type if an error occured or :const:`None`.
+ """:exc:`Exception` type if an error occured or `None`.
.. note::
- This represents an error which prevented a reply from being
- received. An *<rpc-error>* does not fall in that category -- see
- :class:`RPCReply` for that.
+ This represents an error which prevented a reply from being received. An *rpc-error*
+ does not fall in that category -- see `RPCReply` for that.
"""
return self._error
-
+
@property
def id(self):
- "The *message-id* for this RPC"
+ "The *message-id* for this RPC."
return self._id
-
+
@property
def session(self):
- """The :class:`~ncclient.transport.Session` object associated with this
- RPC"""
+ "The `~ncclient.transport.Session` object associated with this RPC."
return self._session
@property
def event(self):
- """:class:`~threading.Event` that is set when reply has been received or
- error occured."""
+ """:class:`~threading.Event` that is set when reply has been received or when an error preventing
+ delivery of the reply occurs.
+ """
return self._event
- def set_async(self, async=True):
- """Set asynchronous mode for this RPC."""
+ def __set_async(self, async=True):
self._async = async
if async and not session.can_pipeline:
raise UserWarning('Asynchronous mode not supported for this device/session')
- def set_raise_mode(self, mode):
+ def __set_raise_mode(self, mode):
assert(choice in ("all", "errors", "none"))
self._raise_mode = mode
- def set_timeout(self, timeout):
- """Set the timeout for synchronous waiting; defining how long the RPC
- request will block on a reply before raising an error. Irrelevant for
- asynchronous usage."""
+ def __set_timeout(self, timeout):
self._timeout = timeout
- #: Whether this RPC is asynchronous
- is_async = property(fget=lambda self: self._async, fset=set_async)
-
- #: Timeout for synchronous waiting
- timeout = property(fget=lambda self: self._timeout, fset=set_timeout)
+ raise_mode = property(fget=lambda self: self._raise_mode, fset=__set_raise_mode)
+ """Depending on this exception raising mode, an `rpc-error` in the reply may be raised as an :exc:`RPCError` exception. Valid values are the constants defined in :class:`RaiseMode`. """
+
+ is_async = property(fget=lambda self: self._async, fset=__set_async)
+ """Specifies whether this RPC will be / was requested asynchronously. By default RPC's are synchronous."""
+
+ timeout = property(fget=lambda self: self._timeout, fset=__set_timeout)
+ """Timeout in seconds for synchronous waiting defining how long the RPC request will block on a reply before raising :exc:`TimeoutExpiredError`.
+
+ Irrelevant for asynchronous usage.
+ """