Lukas Bednar has uploaded a new change for review.
Change subject: Implementation of machine dialog parser for python
......................................................................
Implementation of machine dialog parser for python
Change-Id: Ia7b715a39840e548ef768ac9e77004cc0d98a9c0
Signed-off-by: Lukas Bednar <lbed...@redhat.com>
---
A src/otopi/machine_dialog_parser.py
1 file changed, 508 insertions(+), 0 deletions(-)
git pull ssh://gerrit.ovirt.org:29418/otopi refs/changes/80/28180/1
diff --git a/src/otopi/machine_dialog_parser.py
b/src/otopi/machine_dialog_parser.py
new file mode 100644
index 0000000..d7faebe
--- /dev/null
+++ b/src/otopi/machine_dialog_parser.py
@@ -0,0 +1,508 @@
+#
+# otopi -- plugable installer
+# Copyright (C) 2012-2013 Red Hat, Inc.
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+#
+# This library 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
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+#
+
+
+"""
+Module implements machine dialog parser.
+Please refer to README.dialog.
+"""
+
+
+import re
+import logging
+import gettext
+_ = lambda m: gettext.dgettext(message=m, domain='otopi')
+
+
+from . import constants
+from . import util
+
+
+class ParseError(Exception):
+ pass
+
+
+class UnexpectedEOF(ParseError):
+ pass
+
+
+class HeadDoesNotMatch(ParseError):
+ pass
+
+
+class DialogError(ParseError):
+ pass
+
+
+class UnexpectedEventError(DialogError):
+ pass
+
+
+class Event(object):
+ """
+ Base class for otopi dialog events.
+ """
+ head_regex = None
+
+ @classmethod
+ def _parse_head(cls, head):
+ match = cls.head_regex.match(head)
+ if match is None:
+ raise HeadDoesNotMatch(head, cls)
+ return match.groupdict()
+
+ @classmethod
+ def create(cls, head, stream):
+ return cls(**cls._parse_head(head))
+
+ def __str__(self):
+ params = [("%s=%s" % (k, v)) for k, v in self.__dict__.iteritems()]
+ return "%s(%s)" % (self.__class__.__name__, ", ".join(params))
+
+
+@util.export
+class Replyable(object):
+ """
+ Add 'value' attribute to Event, in order to replay.
+ """
+ def __init__(self, *args, **kwargs):
+ super(Replyable, self).__init__()
+ self.value = None
+
+ def response(self):
+ return self._response()
+
+ def _response(self):
+ raise NotImplementedError()
+
+
+@util.export
+class Abortable(Replyable):
+ """
+ Add 'abort' atribute to Event, in order to abort event.
+ """
+ def __init__(self, *args, **kwargs):
+ super(Abortable, self).__init__()
+ self.abort = False
+
+ def _abort(self):
+ raise NotImplementedError()
+
+ def response(self):
+ if self.abort:
+ return self._abort()
+ return super(Abortable, self).response()
+
+
+@util.export
+class NoteEvent(Event):
+ """
+ ^#+ (.*)\n$
+ Group1 - message.
+
+ Every line that begins with '#' is ignored by manager. Notes are
+ used to interact with humans.
+ """
+
+ head_regex = re.compile('^#+ (?P<note>.*)$')
+
+ def __init__(self, note):
+ super(NoteEvent, self).__init__()
+ self.note = note
+
+
+@util.export
+class TerminateEvent(Event):
+ """
+ ^***TERMINATE\n$
+
+ Termiante dialog.
+ """
+ head_regex = re.compile('^[*]{3}TERMINATE$')
+
+
+@util.export
+class LogEvent(Event):
+ """
+ ^***L:INFO (.*)\n$
+ ^***L:WARNING (.*)\n$
+ ^***L:ERROR (.*)\n$
+ Group1 - message.
+ """
+ head_regex = re.compile('^[*]{3}L:(?P<severity>INFO|WARNING|ERROR) '
+ '(?P<message>.*)$')
+
+ def __init__(self, severity, message):
+ super(LogEvent, self).__init__()
+ self.severity = severity
+ self.message = message
+
+
+class QueryEvent(Event):
+ """
+ Query based events.
+ """
+ def __init__(self, name):
+ super(QueryEvent, self).__init__()
+ self.name = name
+
+
+@util.export
+class QueryString(QueryEvent, Replyable):
+ """
+ ^***Q:STRING (.*)\n$
+ Group1: variable name.
+ Response:
+ Single line response.
+ """
+ head_regex = re.compile('^[*]{3}Q:STRING (?P<name>.*)$')
+
+ def _response(self):
+ if not isinstance(self.value, basestring) or '\n' in self.value:
+ msg = "QueryString.value must be single-line string, got: %s"
+ raise TypeError(msg % self.value)
+ return self.value
+
+
+@util.export
+class QueryMultiString(QueryEvent, Abortable):
+ """
+ ^***Q:MULTI-STRING (.*) (.*) (.*)\n$
+ Group1: variable name.
+ Group2: boundary.
+ Group3: abort boundary.
+ Response:
+ Multiple line response.
+ Boundary at own line marks end.
+ """
+ head_regex = re.compile('^[*]{3}Q:MULTI-STRING '
+ '(?P<name>[^ ]+) '
+ '(?P<boundary>[^ ]+) '
+ '(?P<abort_boundary>[^ ]+)$')
+
+ def __init__(self, name, boundary, abort_boundary):
+ super(QueryMultiString, self).__init__(name)
+ self.boundary = boundary
+ self.abort_boundary = abort_boundary
+
+ def _response(self):
+ return "%s%s" % (''.join(self.value), self.boundary)
+
+ def _abort(self):
+ return self.abort_boundary
+
+
+@util.export
+class QueryValue(QueryEvent, Abortable):
+ """
+ ^***Q:VALUE (.*)\n$
+ Group1: variable name.
+ Response:
+ ^VALUE (.*)=(.*):(.*)\n$
+ Group1: variable name.
+ Group2: variable type.
+ Group3: variable value.
+ Response:
+ ^ABORT (.*)\n$
+ Group1: variable name.
+ """
+ head_regex = re.compile('^[*]{3}Q:VALUE (?P<name>.*)$')
+
+ def _response(self):
+ type_ = type(self.value).__name__
+ if type_ == 'NoneType':
+ type_ = 'none'
+ return "VALUE %s=%s:%s" % (self.name, type, self.value)
+
+ def _abort(self):
+ return "ABORT %s" % self.name
+
+
+@util.export
+class ConfirmEvent(Event, Abortable):
+ """
+ ^***CONFIRM (.*) (.*)$
+ Group1: id.
+ Group2: description.
+ Response:
+ ^CONFIRM (.*)=(yes|no)\n$
+ Group1: id
+ Group2: response
+ Response:
+ ^ABORT (.*)\n$
+ Group1: variable name.
+ """
+ head_regex = re.compile('^[*]{3}CONFIRM (?P<id_>[^ ]+) '
+ '(?P<description>.*)$')
+ options = ('yes', 'no')
+
+ def __init__(self, id_, description):
+ super(ConfirmEvent, self).__init__()
+ self.id_ = id_
+ self.description = description
+
+ def _response(self):
+ if (not isinstance(self.value, basestring) or
+ self.value not in self.options):
+ msg = "ConfirmEvent.value must be 'yes' or 'no' got: %s"
+ raise TypeError(msg % self.value)
+ return "CONFIRM %s=%s" % (self.id_, self.value)
+
+ def _abort(self):
+ return "ABORT %s" % self.id_
+
+
+class DisplayEvent(Event):
+ """
+ Display based events.
+ """
+ def __init__(self, name):
+ super(DisplayEvent, self).__init__()
+ self.name = name
+
+
+@util.export
+class DisplayValue(DisplayEvent):
+ """
+ ^***D:VALUE (.*)=(.*):(.*)\n$
+ Group1: variable name.
+ Group2: type.
+ Group3: value.
+ """
+ head_regex = re.compile('^[*]{3}D:VALUE '
+ '(?P<name>[^=]+)='
+ '(?P<type_>[^:]+):'
+ '(?P<value>.*)$')
+ types = {'none': lambda x: None,
+ 'str': str,
+ 'int': int,
+ 'bool': lambda x: x.lower() == 'true'}
+
+ def __init__(self, name, type_, value):
+ super(DisplayValue, DisplayEvent).__init__(name)
+ self.value = self.types[type_.lower()](value)
+
+
+@util.export
+class DisplayMultiString(DisplayEvent):
+ """
+ ^***D:MULTI-STRING (.*) (.*)\n$
+ (^.*\n$)*
+ ^(.*)\n$
+ Group1: variable name.
+ Group2: boundary.
+ Group3: content.
+ Group4: boundary.
+ """
+ head_regex = re.compile('^[*]{3}D:MULTI-STRING '
+ '(?P<name>[^ ]+) '
+ '(?P<boundary>.*)$')
+
+ def __init__(self, name, boundary, value=None):
+ super(DisplayValue, self).__init__(name)
+ self.boundary = boundary
+ self.value = value
+
+ def _process_multi_line(self, stream):
+ self.value = []
+ while True:
+ line = stream.readline()
+ if not line:
+ raise UnexpectedEOF()
+ if line.strip() != self.boundary:
+ self.value.append(line)
+ else:
+ break
+
+ @classmethod
+ def create(cls, head, stream):
+ event = super(DisplayMultiString, cls).create(head, stream)
+ event._process_multi_line(stream)
+ return event
+
+
+@util.export
+class MachineDialogParser(object):
+ """
+ Machine dialog parser.
+ """
+ logger = logging.getLogger(name=constants.Log.LOGGER_BASE)
+ event_types = (NoteEvent,
+ TerminateEvent,
+ LogEvent,
+ QueryString,
+ QueryMultiString,
+ QueryValue,
+ ConfirmEvent,
+ DisplayValue,
+ DisplayMultiString)
+
+ def __init__(self, input_=None, output=None, filter_=tuple()):
+ """
+ Keyword arguments:
+ input_ -- file like object
+ output -- file like object
+ filter_ -- list of events which should be skipped by parser.
+ """
+ super(MachineDialogParser, self).__init__()
+ self.output = None
+ self.input_ = None
+ self.set_streams(input_, output)
+ self.filter_ = None
+ self.set_filter(filter_)
+
+ def _write(self, data):
+ """
+ Writes data to output stream
+
+ Keyword arguments:
+ data -- string to be written
+ """
+ self.logger.debug("writing data {{{\n%s\n}}}", data)
+ self.output.write(data)
+ self.output.write('\n')
+ self.output.flush()
+
+ def set_filter(self, filter_):
+ """
+ Set list of events which should be skipped by parser.
+
+ Keyword arguments:
+ filter_ -- list of events
+ """
+ for event in filter_:
+ if not issubclass(event, Event):
+ raise TypeError("%s is not Event's subclass" % event)
+ if issubclass(event, Replyable):
+ if not issubclass(event, Abortable):
+ raise TypeError("%s requires response" % event)
+
+ def set_streams(self, input_, output):
+ self.input_ = input_
+ self.output = output
+
+ def _filter(self, event):
+ if event.__class__ in self.filter_:
+ self.logger.debug("Event is in filter, skipping: %s", event)
+ if isinstance(event, Abortable):
+ self.logger.warn(
+ "Skipped event requires response, aborting: %s", event)
+ event.abort = True
+ self.send_response(event)
+ return True
+ return False
+
+ def next_event(self):
+ """
+ Returns instance of Event
+ """
+ line = self.input_.readline()
+ if not line:
+ raise UnexpectedEOF()
+ for event_type in self.event_types:
+ try:
+ event = event_type.create(self.input_)
+ if self._filter(event):
+ continue
+ self.logger.debug("Next event: %s", event)
+ return event
+ except HeadDoesNotMatch:
+ continue
+ raise HeadDoesNotMatch(line, self.event_types)
+
+ def send_response(self, event):
+ """
+ Sends response for Replyable events.
+
+ Keyword arguments:
+ event -- instance of Replyable event.
+ """
+ self._write(event.response())
+
+ # NOTE: all these methods doesn't fit here,
+ # I would move it to separate class.
+ def cli_env_get(self, key):
+ """
+ Keyword arguments:
+ key -- name of variable
+ Returns value for environment variable
+ """
+ cmd = 'env-get -k %s' % key
+ self._write(cmd)
+
+ event = self.next_event()
+ if not isinstance(event, DisplayEvent):
+ raise UnexpectedEventError(event)
+ return event.value
+
+ def cli_env_set(self, key, value):
+ """
+ Sets given value for given environment variable
+
+ Keyword arguments:
+ key -- name of variable
+ value -- value to be set
+ """
+ cmd = 'env-query'
+ if isinstance(value, (list, tuple)):
+ cmd += '-multi'
+ cmd += " -k %s" % key
+ self._write(cmd)
+
+ event = self.next_event()
+ if not isinstance(event, QueryEvent):
+ raise UnexpectedEventError(event)
+ event.value = value
+ self.send_response(event)
+
+ def cli_download_log(self):
+ """
+ Returns log
+ """
+ self._write('log')
+ event = self.next_event()
+ if isinstance(event, DisplayMultiString):
+ return event.value
+ raise UnexpectedEventError(event)
+
+ def cli_noop(self):
+ """
+ noop command
+ """
+ self._write('noop')
+
+ def cli_quit(self):
+ """
+ quit command
+ """
+ self._write('quit')
+
+ def cli_install(self):
+ """
+ install command
+ """
+ self._write('install')
+
+ def cli_abort(self):
+ """
+ abort command
+ """
+ self._write('abort')
+
+# vim: expandtab tabstop=4 shiftwidth=4
--
To view, visit http://gerrit.ovirt.org/28180
To unsubscribe, visit http://gerrit.ovirt.org/settings
Gerrit-MessageType: newchange
Gerrit-Change-Id: Ia7b715a39840e548ef768ac9e77004cc0d98a9c0
Gerrit-PatchSet: 1
Gerrit-Project: otopi
Gerrit-Branch: master
Gerrit-Owner: Lukas Bednar <lbed...@redhat.com>
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