# coding: UTF-8 '''Mock D-BUS objects for test suites.''' # This program 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 3 of the License, or (at your option) any # later version. See http://www.gnu.org/copyleft/lgpl.html for the full text # of the license. __author__ = 'Martin Pitt' __email__ = 'martin.pitt@ubuntu.com' __copyright__ = '(c) 2012 Canonical Ltd.' __license__ = 'LGPL 3+' import copy import time import sys import types import importlib import imp from xml.etree import ElementTree # we do not use this ourselves, but mock methods often want to use this import os os # pyflakes import dbus import dbus.service # global path -> DBusMockObject mapping objects = {} MOCK_IFACE = 'org.freedesktop.DBus.Mock' OBJECT_MANAGER_IFACE = 'org.freedesktop.DBus.ObjectManager' # stubs to keep code compatible with Python 2 and 3 if sys.version_info[0] >= 3: long = int unicode = str def load_module(name): if os.path.exists(name) and os.path.splitext(name)[1] == '.py': mod = imp.new_module(os.path.splitext(os.path.basename(name))[0]) with open(name) as f: exec(f.read(), mod.__dict__, mod.__dict__) return mod return importlib.import_module('dbusmock.templates.' + name) class DBusMockObject(dbus.service.Object): '''Mock D-Bus object This can be configured to have arbitrary methods (including code execution) and properties via methods on the org.freedesktop.DBus.Mock interface, so that you can control the mock from any programming language. ''' def __init__(self, bus_name, path, interface, props, logfile=None, is_object_manager=False): '''Create a new DBusMockObject bus_name: A dbus.service.BusName instance where the object will be put on path: D-Bus object path interface: Primary D-Bus interface name of this object (where properties and methods will be put on) props: A property_name (string) → property (Variant) map with initial properties on "interface" logfile: When given, method calls will be logged into that file name; if None, logging will be written to stdout. Note that you can also query the called methods over D-BUS with GetCalls() and GetMethodCalls(). is_object_manager: If True, the GetManagedObjects method will automatically be implemented on the object, returning all objects which have this one’s path as a prefix of theirs. Note that the InterfacesAdded and InterfacesRemoved signals will not be automatically emitted. ''' dbus.service.Object.__init__(self, bus_name, path) self.bus_name = bus_name self.path = path self.interface = interface self.is_object_manager = is_object_manager self._template = None self._template_parameters = None if logfile: self.logfile = open(logfile, 'w') else: self.logfile = None self.is_logfile_owner = True self.call_log = [] if props is None: props = {} self._reset(props) def __del__(self): if self.logfile and self.is_logfile_owner: self.logfile.close() def _set_up_object_manager(self): '''Set up this mock object as a D-Bus ObjectManager.''' if self.path == '/': cond = 'k != \'/\'' else: cond = 'k.startswith(\'%s/\')' % self.path self.AddMethod(OBJECT_MANAGER_IFACE, 'GetManagedObjects', '', 'a{oa{sa{sv}}}', 'ret = {dbus.ObjectPath(k): objects[k].props ' + ' for k in objects.keys() if ' + cond + '}') def _reset(self, props): # interface -> name -> value self.props = {self.interface: props} # interface -> name -> (in_signature, out_signature, code, dbus_wrapper_fn) self.methods = {self.interface: {}} if self.is_object_manager: self._set_up_object_manager() @dbus.service.method(dbus.PROPERTIES_IFACE, in_signature='ss', out_signature='v') def Get(self, interface_name, property_name): '''Standard D-Bus API for getting a property value''' self.log('Get %s.%s' % (interface_name, property_name)) if not interface_name: interface_name = self.interface try: return self.GetAll(interface_name)[property_name] except KeyError: raise dbus.exceptions.DBusException( self.interface + '.UnknownProperty', 'no such property ' + property_name) @dbus.service.method(dbus.PROPERTIES_IFACE, in_signature='s', out_signature='a{sv}') def GetAll(self, interface_name, *args, **kwargs): '''Standard D-Bus API for getting all property values''' self.log('GetAll ' + interface_name) if not interface_name: interface_name = self.interface try: return self.props[interface_name] except KeyError: raise dbus.exceptions.DBusException( self.interface + '.UnknownInterface', 'no such interface ' + interface_name) @dbus.service.method(dbus.PROPERTIES_IFACE, in_signature='ssv', out_signature='') def Set(self, interface_name, property_name, value, *args, **kwargs): '''Standard D-Bus API for setting a property value''' self.log('Set %s.%s%s' % (interface_name, property_name, self.format_args((value,)))) try: iface_props = self.props[interface_name] except KeyError: raise dbus.exceptions.DBusException( self.interface + '.UnknownInterface', 'no such interface ' + interface_name) if property_name not in iface_props: raise dbus.exceptions.DBusException( self.interface + '.UnknownProperty', 'no such property ' + property_name) iface_props[property_name] = value @dbus.service.method(MOCK_IFACE, in_signature='ssa{sv}a(ssss)', out_signature='') def AddObject(self, path, interface, properties, methods): '''Add a new D-Bus object to the mock path: D-Bus object path interface: Primary D-Bus interface name of this object (where properties and methods will be put on) properties: A property_name (string) → value map with initial properties on "interface" methods: An array of 4-tuples (name, in_sig, out_sig, code) describing methods to add to "interface"; see AddMethod() for details of the tuple values If this is a D-Bus ObjectManager instance, the InterfacesAdded signal will *not* be emitted for the object automatically; it must be emitted manually if desired. This is because AddInterface may be called after AddObject, but before the InterfacesAdded signal should be emitted. Example: dbus_proxy.AddObject('/com/example/Foo/Manager', 'com.example.Foo.Control', { 'state': dbus.String('online', variant_level=1), }, [ ('Start', '', '', ''), ('EchoInt', 'i', 'i', 'ret = args[0]'), ('GetClients', '', 'ao', 'ret = ["/com/example/Foo/Client1"]'), ]) ''' if path in objects: raise dbus.exceptions.DBusException( 'org.freedesktop.DBus.Mock.NameError', 'object %s already exists' % path) obj = DBusMockObject(self.bus_name, path, interface, properties) # make sure created objects inherit the log file stream obj.logfile = self.logfile obj.is_logfile_owner = False obj.AddMethods(interface, methods) objects[path] = obj @dbus.service.method(MOCK_IFACE, in_signature='s', out_signature='') def RemoveObject(self, path): '''Remove a D-Bus object from the mock As with AddObject, this will *not* emit the InterfacesRemoved signal if it’s an ObjectManager instance. ''' try: objects[path].remove_from_connection() del objects[path] except KeyError: raise dbus.exceptions.DBusException( 'org.freedesktop.DBus.Mock.NameError', 'object %s does not exist' % path) @dbus.service.method(MOCK_IFACE, in_signature='', out_signature='') def Reset(self): '''Reset the mock object state. Remove all mock objects from the bus and tidy up so the state is as if python-dbusmock had just been restarted. If the mock object was originally created with a template (from the command line, the Python API or by calling AddTemplate over D-Bus), it will be re-instantiated with that template. ''' # Clear other existing objects. for obj_name, obj in objects.items(): if obj_name != self.path: obj.remove_from_connection() objects.clear() # Reinitialise our state. Carefully remove new methods from our dict; # they don't not actually exist if they are a statically defined # template function for method_name in self.methods[self.interface]: try: delattr(self.__class__, method_name) except AttributeError: pass self._reset({}) if self._template is not None: self.AddTemplate(self._template, self._template_parameters) objects[self.path] = self @dbus.service.method(MOCK_IFACE, in_signature='sssss', out_signature='') def AddMethod(self, interface, name, in_sig, out_sig, code): '''Add a method to this object interface: D-Bus interface to add this to. For convenience you can specify '' here to add the method to the object's main interface (as specified on construction). name: Name of the method in_sig: Signature of input arguments; for example "ias" for a method that takes an int32 and a string array as arguments; see http://dbus.freedesktop.org/doc/dbus-specification.html#message-protocol-signatures out_sig: Signature of output arguments; for example "s" for a method that returns a string; use '' for methods that do not return anything. code: Python 3 code to run in the method call; you have access to the arguments through the "args" list, and can set the return value by assigning a value to the "ret" variable. You can also read the global "objects" variable, which is a dictionary mapping object paths to DBusMockObject instances. For keeping state across method calls, you are free to use normal Python members of the "self" object, which will be persistant for the whole mock's life time. E. g. you can have a method with "self.my_state = True", and another method that returns it with "ret = self.my_state". When specifying '', the method will not do anything (except logging) and return None. ''' if not interface: interface = self.interface n_args = len(dbus.Signature(in_sig)) # we need to have separate methods for dbus-python, so clone # mock_method(); using message_keyword with this dynamic approach fails # because inspect cannot handle those, so pass on interface and method # name as first positional arguments method = lambda self, *args, **kwargs: DBusMockObject.mock_method( self, interface, name, in_sig, *args, **kwargs) # we cannot specify in_signature here, as that trips over a consistency # check in dbus-python; we need to set it manually instead dbus_method = dbus.service.method(interface, out_signature=out_sig)(method) dbus_method.__name__ = str(name) dbus_method._dbus_in_signature = in_sig dbus_method._dbus_args = ['arg%i' % i for i in range(1, n_args + 1)] # for convenience, add mocked methods on the primary interface as # callable methods if interface == self.interface: setattr(self.__class__, name, dbus_method) self.methods.setdefault(interface, {})[str(name)] = (in_sig, out_sig, code, dbus_method) @dbus.service.method(MOCK_IFACE, in_signature='sa(ssss)', out_signature='') def AddMethods(self, interface, methods): '''Add several methods to this object interface: D-Bus interface to add this to. For convenience you can specify '' here to add the method to the object's main interface (as specified on construction). methods: list of 4-tuples (name, in_sig, out_sig, code) describing one method each. See AddMethod() for details of the tuple values. ''' for method in methods: self.AddMethod(interface, *method) @dbus.service.method(MOCK_IFACE, in_signature='ssv', out_signature='') def AddProperty(self, interface, name, value): '''Add property to this object interface: D-Bus interface to add this to. For convenience you can specify '' here to add the property to the object's main interface (as specified on construction). name: Property name. value: Property value. ''' if not interface: interface = self.interface try: self.props[interface][name] raise dbus.exceptions.DBusException( self.interface + '.PropertyExists', 'property %s already exists' % name) except KeyError: # this is what we expect pass # copy.copy removes one level of variant-ness, which means that the # types get exported in introspection data correctly, but we can't do # this for container types. if not (isinstance(value, dbus.Dictionary) or isinstance(value, dbus.Array)): value = copy.copy(value) self.props.setdefault(interface, {})[name] = value @dbus.service.method(MOCK_IFACE, in_signature='sa{sv}', out_signature='') def AddProperties(self, interface, properties): '''Add several properties to this object interface: D-Bus interface to add this to. For convenience you can specify '' here to add the property to the object's main interface (as specified on construction). properties: A property_name (string) → value map ''' for k, v in properties.items(): self.AddProperty(interface, k, v) @dbus.service.method(MOCK_IFACE, in_signature='sa{sv}', out_signature='') def AddTemplate(self, template, parameters): '''Load a template into the mock. python-dbusmock ships a set of standard mocks for common system services such as UPower and NetworkManager. With these the actual tests become a lot simpler, as they only have to set up the particular properties for the tests, and not the skeleton of common properties, interfaces, and methods. template: Name of the template to load or the full path to a *.py file for custom templates. See "pydoc dbusmock.templates" for a list of available templates from python-dbusmock package, and "pydoc dbusmock.templates.NAME" for documentation about template NAME. parameters: A parameter (string) → value (variant) map, for parameterizing templates. Each template can define their own, see documentation of that particular template for details. ''' try: module = load_module(template) except ImportError as e: raise dbus.exceptions.DBusException('Cannot add template %s: %s' % (template, str(e))) # If the template specifies this is an ObjectManager, set that up if hasattr(module, 'IS_OBJECT_MANAGER') and module.IS_OBJECT_MANAGER: self._set_up_object_manager() # pick out all D-BUS service methods and add them to our interface for symbol in dir(module): fn = getattr(module, symbol) if ('_dbus_interface' in dir(fn) and ('_dbus_is_signal' not in dir(fn) or not fn._dbus_is_signal)): # for dbus-python compatibility, add methods as callables setattr(self.__class__, symbol, fn) self.methods.setdefault(fn._dbus_interface, {})[str(symbol)] = ( fn._dbus_in_signature, fn._dbus_out_signature, '', fn ) if parameters is None: parameters = {} module.load(self, parameters) # save the given template and parameters for re-instantiation on # Reset() self._template = template self._template_parameters = parameters @dbus.service.method(MOCK_IFACE, in_signature='sssav', out_signature='') def EmitSignal(self, interface, name, signature, args): '''Emit a signal from the object. interface: D-Bus interface to send the signal from. For convenience you can specify '' here to add the method to the object's main interface (as specified on construction). name: Name of the signal signature: Signature of input arguments; for example "ias" for a signal that takes an int32 and a string array as arguments; see http://dbus.freedesktop.org/doc/dbus-specification.html#message-protocol-signatures args: variant array with signal arguments; must match order and type in "signature" ''' if not interface: interface = self.interface # convert types of arguments according to signature, using # MethodCallMessage.append(); this will also provide type/length # checks, except for the case of an empty signature if signature == '' and len(args) > 0: raise TypeError('Fewer items found in D-Bus signature than in Python arguments') m = dbus.connection.MethodCallMessage('a.b', '/a', 'a.b', 'a') m.append(signature=signature, *args) args = m.get_args_list() fn = lambda self, *args: self.log('emit %s.%s%s' % (interface, name, self.format_args(args))) fn.__name__ = str(name) dbus_fn = dbus.service.signal(interface)(fn) dbus_fn._dbus_signature = signature dbus_fn._dbus_args = ['arg%i' % i for i in range(1, len(args) + 1)] dbus_fn(self, *args) @dbus.service.method(MOCK_IFACE, in_signature='', out_signature='a(tsav)') def GetCalls(self): '''List all the logged calls since the last call to ClearCalls(). Return a list of (timestamp, method_name, args_list) tuples. ''' return self.call_log @dbus.service.method(MOCK_IFACE, in_signature='s', out_signature='a(tav)') def GetMethodCalls(self, method): '''List all the logged calls of a particular method. Return a list of (timestamp, args_list) tuples. ''' return [(row[0], row[2]) for row in self.call_log if row[1] == method] @dbus.service.method(MOCK_IFACE, in_signature='', out_signature='') def ClearCalls(self): '''Empty the log of mock call signatures.''' self.call_log = [] @dbus.service.signal(MOCK_IFACE, signature='sav') def MethodCalled(self, name, args): '''Signal emitted for every called mock method. This is emitted for all mock method calls. This can be used to confirm that a particular method was called with particular arguments, as an alternative to reading the mock's log or GetCalls(). ''' pass def mock_method(self, interface, dbus_method, in_signature, *args, **kwargs): '''Master mock method. This gets "instantiated" in AddMethod(). Execute the code snippet of the method and return the "ret" variable if it was set. ''' # print('mock_method', dbus_method, self, in_signature, args, kwargs, file=sys.stderr) # convert types of arguments according to signature, using # MethodCallMessage.append(); this will also provide type/length # checks, except for the case of an empty signature if in_signature == '' and len(args) > 0: raise TypeError('Fewer items found in D-Bus signature than in Python arguments') m = dbus.connection.MethodCallMessage('a.b', '/a', 'a.b', 'a') m.append(signature=in_signature, *args) args = m.get_args_list() self.log(dbus_method + self.format_args(args)) self.call_log.append((int(time.time()), str(dbus_method), args)) self.MethodCalled(dbus_method, args) # The code may be a Python 3 string to interpret, or may be a function # object (if AddMethod was called from within Python itself, rather than # over D-Bus). code = self.methods[interface][dbus_method][2] if code and isinstance(code, types.FunctionType): return code(self, *args) elif code: loc = locals().copy() exec(code, globals(), loc) if 'ret' in loc: return loc['ret'] def format_args(self, args): '''Format a D-BUS argument tuple into an appropriate logging string.''' def format_arg(a): if isinstance(a, dbus.Boolean): return str(bool(a)) if isinstance(a, dbus.Byte): return str(int(a)) if isinstance(a, int) or isinstance(a, long): return str(a) if isinstance(a, str) or isinstance(a, unicode): return '"' + str(a) + '"' if isinstance(a, list): return '[' + ', '.join([format_arg(x) for x in a]) + ']' if isinstance(a, dict): fmta = '{' first = True for k, v in a.items(): if first: first = False else: fmta += ', ' fmta += format_arg(k) + ': ' + format_arg(v) return fmta + '}' # fallback return repr(a) s = '' for a in args: if s: s += ' ' s += format_arg(a) if s: s = ' ' + s return s def log(self, msg): '''Log a message, prefixed with a timestamp. If a log file was specified in the constructor, it is written there, otherwise it goes to stdout. ''' if self.logfile: fd = self.logfile else: fd = sys.stdout fd.write('%.3f %s\n' % (time.time(), msg)) fd.flush() @dbus.service.method(dbus.INTROSPECTABLE_IFACE, in_signature='', out_signature='s', path_keyword='object_path', connection_keyword='connection') def Introspect(self, object_path, connection): '''Return XML description of this object's interfaces, methods and signals. This wraps dbus-python's Introspect() method to include the dynamic methods and properties. ''' # temporarily add our dynamic methods cls = self.__class__.__module__ + '.' + self.__class__.__name__ orig_interfaces = self._dbus_class_table[cls] mock_interfaces = orig_interfaces.copy() for interface, methods in self.methods.items(): for method in methods: mock_interfaces.setdefault(interface, {})[method] = self.methods[interface][method][3] self._dbus_class_table[cls] = mock_interfaces xml = dbus.service.Object.Introspect(self, object_path, connection) tree = ElementTree.fromstring(xml) for name in self.props: # We might have properties for new interfaces we don't know about # yet. Try to find an existing node named after our # interface to append to, and create one if we can't. interface = tree.find(".//interface[@name='%s']" % name) if interface is None: interface = ElementTree.Element("interface", {"name": name}) tree.append(interface) for prop, val in self.props[name].items(): if val is None: # can't guess type from None, skip continue elem = ElementTree.Element("property", { "name": prop, # We don't store the signature anywhere, so guess it. "type": dbus.lowlevel.Message.guess_signature(val), "access": "readwrite"}) interface.append(elem) xml = ElementTree.tostring(tree, encoding='utf8', method='xml').decode('utf8') # restore original class table self._dbus_class_table[cls] = orig_interfaces return xml # Overwrite dbus-python's _method_lookup(), as that offers no way to have the # same method name on different interfaces orig_method_lookup = dbus.service._method_lookup def _dbusmock_method_lookup(obj, method_name, dbus_interface): try: m = obj.methods[dbus_interface or obj.interface][method_name] return (m[3], m[3]) except KeyError: return orig_method_lookup(obj, method_name, dbus_interface) dbus.service._method_lookup = _dbusmock_method_lookup # # Helper API for templates # def get_objects(): '''Return all existing object paths''' return objects.keys() def get_object(path): '''Return object for a given object path''' return objects[path]