bridbe(pb): Perspective Broker bridge, first draft

src/bridge/bridge_constructor/constructors/pb/constructor.py

@@ -0,0 +1,56 @@
+#!/usr/bin/env python2
+#-*- coding: utf-8 -*-
+
+# SàT: a XMPP client
+# Copyright (C) 2009-2016 Jérôme Poisson (goffi@goffi.org)
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero 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 Affero General Public License for more details.
+
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from sat.bridge.bridge_constructor import base_constructor
+
+
+class pbConstructor(base_constructor.Constructor):
+    NAME = "pb"
+    CORE_TEMPLATE = "pb_core_template.py"
+    CORE_DEST = "pb.py"
+    CORE_FORMATS = {
+        'signals': """\
+    def {name}(self, {args}):
+        {debug}self.sendSignal("{name}", {args_no_def})\n""",
+        }
+
+    FRONTEND_TEMPLATE = "pb_frontend_template.py"
+    FRONTEND_DEST = CORE_DEST
+    FRONTEND_FORMATS = {
+        'methods': """\
+    def {name}(self{args_comma}{args}, callback=None, errback=None):
+        {debug}d = self.root.callRemote("{name}"{args_comma}{args_no_def})
+        if callback is not None:
+            d.addCallback({callback})
+        if errback is None:
+            errback = self._generic_errback
+        d.addErrback(errback)\n""",
+        }
+
+    def core_completion_signal(self, completion, function, default, arg_doc, async_):
+        completion['args_no_def'] = self.getArguments(function['sig_in'], name=arg_doc)
+        completion['debug'] = "" if not self.args.debug else 'log.debug ("%s")\n%s' % (completion['name'], 8 * ' ')
+
+    def frontend_completion_method(self, completion, function, default, arg_doc, async_):
+        completion.update({
+            'args_comma': ', ' if function['sig_in'] else '',
+            'args_no_def': self.getArguments(function['sig_in'], name=arg_doc),
+            'callback': 'callback' if function['sig_out'] else 'lambda dummy: callback()',
+            'debug': "" if not self.args.debug else 'log.debug ("%s")\n%s' % (completion['name'], 8 * ' '),
+            })

src/bridge/bridge_constructor/constructors/pb/pb_core_template.py

@@ -0,0 +1,101 @@
+#!/usr/bin/env python2
+#-*- coding: utf-8 -*-
+
+# SAT: a jabber client
+# Copyright (C) 2009-2016 Jérôme Poisson (goffi@goffi.org)
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero 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 Affero General Public License for more details.
+
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+
+from sat.core.log import getLogger
+log = getLogger(__name__)
+from twisted.spread import jelly, pb
+from twisted.internet import reactor
+
+
+## jelly hack
+# we monkey patch jelly to handle namedtuple
+ori_jelly = jelly._Jellier.jelly
+
+def fixed_jelly(self, obj):
+    """this method fix handling of namedtuple"""
+    if isinstance(obj, tuple) and not obj is tuple:
+        obj = tuple(obj)
+    return ori_jelly(self, obj)
+
+jelly._Jellier.jelly = fixed_jelly
+
+
+class PBRoot(pb.Root):
+
+    def __init__(self):
+        self.signals_handlers = []
+
+    def remote_initBridge(self, signals_handler):
+        self.signals_handlers.append(signals_handler)
+        log.info(u"registered signal handler")
+
+    def sendSignalEb(self, failure, signal_name):
+        log.error(u"Error while sending signal {name}: {msg}".format(
+            name = signal_name,
+            msg = failure,
+            ))
+
+    def sendSignal(self, name, args, kwargs):
+        to_remove = []
+        for handler in self.signals_handlers:
+            try:
+                d = handler.callRemote(name, *args, **kwargs)
+            except pb.DeadReferenceError:
+                to_remove.append(handler)
+            else:
+                d.addErrback(self.sendSignalEb, name)
+        if to_remove:
+            for handler in to_remove:
+                log.debug(u"Removing signal handler for dead frontend")
+                self.signals_handlers.remove(handler)
+
+##METHODS_PART##
+
+
+class Bridge(object):
+
+    def __init__(self):
+        log.info("Init Perspective Broker...")
+        self.root = PBRoot()
+        reactor.listenTCP(8789, pb.PBServerFactory(self.root))
+
+    def sendSignal(self, name, *args, **kwargs):
+        self.root.sendSignal(name, args, kwargs)
+
+    def remote_initBridge(self, signals_handler):
+        self.signals_handlers.append(signals_handler)
+        log.info(u"registered signal handler")
+
+    def register_method(self, name, callback):
+        log.debug("registering PB bridge method [%s]" % name)
+        setattr(self.root, "remote_"+name, callback)
+        # self.root.register_method(name, callback)
+
+    def addMethod(self, name, int_suffix, in_sign, out_sign, method, async=False, doc={}):
+        """Dynamically add a method to PB Bridge"""
+        #FIXME: doc parameter is kept only temporary, the time to remove it from calls
+        log.debug("Adding method {name} to PB bridge".format(name=name))
+        self.register_method(name, method)
+
+    def addSignal(self, name, int_suffix, signature, doc={}):
+        log.debug("Adding signal {name} to PB bridge".format(name=name))
+        setattr(self, name, lambda *args, **kwargs: self.sendSignal(name, *args, **kwargs))
+
+##SIGNALS_PART##

src/bridge/bridge_constructor/constructors/pb/pb_frontend_template.py

@@ -0,0 +1,127 @@
+#!/usr/bin/env python2
+#-*- coding: utf-8 -*-
+
+# SAT communication bridge
+# Copyright (C) 2009-2016 Jérôme Poisson (goffi@goffi.org)
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero 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 Affero General Public License for more details.
+
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from sat.core.log import getLogger
+log = getLogger(__name__)
+from sat.core import exceptions
+from twisted.spread import pb
+from twisted.internet import reactor
+
+
+class SignalsHandler(pb.Referenceable):
+
+    def __getattr__(self, name):
+        if name.startswith("remote_"):
+            log.debug(u"calling an unregistered signal: {name}".format(
+                name = name[7:]))
+            return lambda *args, **kwargs: None
+
+        else:
+            raise AttributeError(name)
+
+    def register_signal(self, name, handler, iface="core"):
+        log.debug("registering signal {name}".format(name=name))
+        method_name = "remote_" + name
+        try:
+            self.__getattribute__(self, method_name)
+        except AttributeError:
+            pass
+        else:
+            raise exceptions.InternalError(u"{name} signal handler has been registered twice".format(
+                name = method_name))
+        setattr(self, method_name, handler)
+
+
+class Bridge(object):
+
+    def __init__(self):
+        self.signals_handler = SignalsHandler()
+
+    def __getattr__(self, name):
+        return lambda *args, **kwargs: self.call(name, args, kwargs)
+
+    def remoteCallback(self, result, callback):
+        """call callback with argument or None
+
+        if result is not None not argument is used,
+        else result is used as argument
+        @param result: remote call result
+        @param callback(callable): method to call on result
+        """
+        if result is None:
+            callback()
+        else:
+            callback(result)
+
+    def call(self, name, args, kwargs):
+        """call a remote method
+
+        @param name(str): name of the bridge method
+        @param args(list): arguments
+            may contain callback and errback as last 2 items
+        @param kwargs(dict): keyword arguments
+            may contain callback and errback
+        """
+        callback = errback = None
+        if kwargs:
+            try:
+                callback = kwargs.pop('callback')
+            except KeyError:
+                pass
+            try:
+                errback = kwargs.pop('errback')
+            except KeyError:
+                pass
+        elif len(args) >= 2 and callable(args[-1]) and callable(args[-2]):
+            errback = args.pop()
+            callback = args.pop()
+        d = self.root.callRemote(name, *args, **kwargs)
+        if callback is not None:
+            d.addCallback(self.remoteCallback, callback)
+        if errback is not None:
+            d.addErrback(errback)
+
+    def _initBridgeEb(self, failure):
+        log.error(u"Can't init bridge: {msg}".format(msg=failure))
+
+    def _set_root(self, root):
+        """set remote root object
+
+        bridge will then be initialised
+        """
+        self.root = root
+        d = root.callRemote("initBridge", self.signals_handler)
+        d.addErrback(self._initBridgeEb)
+        return d
+
+    def _generic_errback(self, failure):
+        log.error(u"bridge failure: {}".format(failure))
+
+    def bridgeConnect(self, callback, errback):
+        factory = pb.PBClientFactory()
+        reactor.connectTCP("localhost", 8789, factory)
+        d = factory.getRootObject()
+        d.addCallback(self._set_root)
+        d.addCallback(lambda dummy: callback())
+        d.addErrback(errback)
+
+    def register_signal(self, functionName, handler, iface="core"):
+        self.signals_handler.register_signal(functionName, handler, iface)
+
+##METHODS_PART##