X-Git-Url: https://git.llucax.com/software/pymin.git/blobdiff_plain/f5a081744ba31beed226db828e0e16a01ec77c83..f1bb67630d2233b46673806941bd71b22e6147ab:/pymin/services/util.py diff --git a/pymin/services/util.py b/pymin/services/util.py index 95a07e9..418616b 100644 --- a/pymin/services/util.py +++ b/pymin/services/util.py @@ -15,10 +15,13 @@ from pymin.dispatcher import Handler, handler, HandlerError, \ #DEBUG = False DEBUG = True -__ALL__ = ('ServiceHandler', 'InitdHandler', 'SubHandler', 'DictSubHandler', - 'ListSubHandler', 'Persistent', 'ConfigWriter', 'Error', - 'ReturnNot0Error', 'ExecutionError', 'ItemError', - 'ItemAlreadyExistsError', 'ItemNotFoundError', 'call') +__ALL__ = ('Error', 'ReturnNot0Error', 'ExecutionError', 'ItemError', + 'ItemAlreadyExistsError', 'ItemNotFoundError', 'ContainerError', + 'ContainerNotFoundError', 'call', 'get_network_devices', + 'Persistent', 'Restorable', 'ConfigWriter', 'ServiceHandler', + 'RestartHandler', 'ReloadHandler', 'InitdHandler', 'SubHandler', + 'DictSubHandler', 'ListSubHandler', 'ComposedSubHandler', + 'ListComposedSubHandler', 'DictComposedSubHandler') class Error(HandlerError): r""" @@ -116,7 +119,7 @@ class ItemAlreadyExistsError(ItemError): class ItemNotFoundError(ItemError): r""" - ItemNotFoundError(key) -> ItemNotFoundError instance + ItemNotFoundError(key) -> ItemNotFoundError instance. This exception is raised when trying to operate on an item that doesn't exists. @@ -126,6 +129,44 @@ class ItemNotFoundError(ItemError): r"Initialize the object. See class documentation for more info." self.message = u'Item not found: "%s"' % key +class ContainerError(Error, KeyError): + r""" + ContainerError(key) -> ContainerError instance. + + This is the base exception for all container related errors. + """ + + def __init__(self, key): + r"Initialize the object. See class documentation for more info." + self.message = u'Container error: "%s"' % key + +class ContainerNotFoundError(ContainerError): + r""" + ContainerNotFoundError(key) -> ContainerNotFoundError instance. + + This exception is raised when trying to operate on an container that + doesn't exists. + """ + + def __init__(self, key): + r"Initialize the object. See class documentation for more info." + self.message = u'Container not found: "%s"' % key + + +def get_network_devices(): + p = subprocess.Popen(('ip', 'link', 'list'), stdout=subprocess.PIPE, + close_fds=True) + string = p.stdout.read() + p.wait() + d = dict() + i = string.find('eth') + while i != -1: + eth = string[i:i+4] + m = string.find('link/ether', i+4) + mac = string[ m+11 : m+11+17] + d[eth] = mac + i = string.find('eth', m+11+17) + return d def call(command, stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE, close_fds=True, universal_newlines=True, @@ -447,6 +488,32 @@ class ServiceHandler(Handler): r"reload() -> None :: Reload the configuration of the service." call(self._service_reload) +class RestartHandler(Handler): + r"""RestartHandler() -> RestartHandler :: Provides generic restart command. + + This is a helper class to inherit from to automatically add a restart + command that first stop the service and then starts it again (using start + and stop commands respectively). + """ + + @handler(u'Restart the service (alias to stop + start).') + def restart(self): + r"restart() -> None :: Restart the service calling stop() and start()." + self.stop() + self.start() + +class ReloadHandler(Handler): + r"""ReloadHandler() -> ReloadHandler :: Provides generic reload command. + + This is a helper class to inherit from to automatically add a reload + command that calls restart. + """ + + @handler(u'Reload the service config (alias to restart).') + def reload(self): + r"reload() -> None :: Reload the configuration of the service." + self.restart() + class InitdHandler(Handler): r"""InitdHandler([initd_name[, initd_dir]]) -> InitdHandler. @@ -590,162 +657,354 @@ class SubHandler(Handler): r"Initialize the object, see the class documentation for details." self.parent = parent -class ListSubHandler(SubHandler): - r"""ListSubHandler(parent) -> ListSubHandler instance. - - This is a helper class to inherit from to automatically handle subcommands - that operates over a list parent attribute. - - The list attribute to handle and the class of objects that it contains can - be defined by calling the constructor or in a more declarative way as - class attributes, like: - - class TestHandler(ListSubHandler): - _list_subhandler_attr = 'some_list' - _list_subhandler_class = SomeClass - - This way, the parent's some_list attribute (self.parent.some_list) will be - managed automatically, providing the commands: add, update, delete, get, - list and show. New items will be instances of SomeClass, which should - provide a cmp operator to see if the item is on the list and an update() - method, if it should be possible to modify it. +class ContainerSubHandler(SubHandler): + r"""ContainerSubHandler(parent) -> ContainerSubHandler instance. + + This is a helper class to implement ListSubHandler and DictSubHandler. You + should not use it directly. + + The container attribute to handle and the class of objects that it + contains can be defined by calling the constructor or in a more declarative + way as class attributes, like: + + class TestHandler(ContainerSubHandler): + _cont_subhandler_attr = 'some_cont' + _cont_subhandler_class = SomeClass + + This way, the parent's some_cont attribute (self.parent.some_cont) + will be managed automatically, providing the commands: add, update, + delete, get and show. New items will be instances of SomeClass, + which should provide a cmp operator to see if the item is on the + container and an update() method, if it should be possible to modify + it. If SomeClass has an _add, _update or _delete attribute, it set + them to true when the item is added, updated or deleted respectively + (in case that it's deleted, it's not removed from the container, + but it's not listed either). """ def __init__(self, parent, attr=None, cls=None): r"Initialize the object, see the class documentation for details." self.parent = parent if attr is not None: - self._list_subhandler_attr = attr + self._cont_subhandler_attr = attr if cls is not None: - self._list_subhandler_class = cls + self._cont_subhandler_class = cls + + def _attr(self, attr=None): + if attr is None: + return getattr(self.parent, self._cont_subhandler_attr) + setattr(self.parent, self._cont_subhandler_attr, attr) - def _list(self): - return getattr(self.parent, self._list_subhandler_attr) + def _vattr(self): + if isinstance(self._attr(), dict): + return dict([(k, i) for (k, i) in self._attr().items() + if not hasattr(i, '_delete') or not i._delete]) + return [i for i in self._attr() + if not hasattr(i, '_delete') or not i._delete] @handler(u'Add a new item') def add(self, *args, **kwargs): r"add(...) -> None :: Add an item to the list." - item = self._list_subhandler_class(*args, **kwargs) - if item in self._list(): + item = self._cont_subhandler_class(*args, **kwargs) + if hasattr(item, '_add'): + item._add = True + key = item + if isinstance(self._attr(), dict): + key = item.as_tuple()[0] + # do we have the same item? then raise an error + if key in self._vattr(): raise ItemAlreadyExistsError(item) - self._list().append(item) + # do we have the same item, but logically deleted? then update flags + if key in self._attr(): + index = key + if not isinstance(self._attr(), dict): + index = self._attr().index(item) + if hasattr(item, '_add'): + self._attr()[index]._add = False + if hasattr(item, '_delete'): + self._attr()[index]._delete = False + else: # it's *really* new + if isinstance(self._attr(), dict): + self._attr()[key] = item + else: + self._attr().append(item) @handler(u'Update an item') def update(self, index, *args, **kwargs): - r"update(index, ...) -> None :: Update an item of the list." + r"update(index, ...) -> None :: Update an item of the container." # TODO make it right with metaclasses, so the method is not created # unless the update() method really exists. # TODO check if the modified item is the same of an existing one - index = int(index) # TODO validation - if not hasattr(self._list_subhandler_class, 'update'): + if not isinstance(self._attr(), dict): + index = int(index) # TODO validation + if not hasattr(self._cont_subhandler_class, 'update'): raise CommandNotFoundError(('update',)) try: - self._list()[index].update(*args, **kwargs) - except IndexError: + item = self._vattr()[index] + item.update(*args, **kwargs) + if hasattr(item, '_update'): + item._update = True + except LookupError: raise ItemNotFoundError(index) @handler(u'Delete an item') def delete(self, index): - r"delete(index) -> None :: Delete an item of the list." - index = int(index) # TODO validation + r"delete(index) -> None :: Delete an item of the container." + if not isinstance(self._attr(), dict): + index = int(index) # TODO validation try: - return self._list().pop(index) - except IndexError: + item = self._vattr()[index] + if hasattr(item, '_delete'): + item._delete = True + else: + del self._attr()[index] + return item + except LookupError: raise ItemNotFoundError(index) + @handler(u'Remove all items (use with care).') + def clear(self): + r"clear() -> None :: Delete all items of the container." + if isinstance(self._attr(), dict): + self._attr.clear() + else: + self._attr(list()) + @handler(u'Get information about an item') def get(self, index): - r"get(index) -> Host :: List all the information of an item." - index = int(index) # TODO validation + r"get(index) -> item :: List all the information of an item." + if not isinstance(self._attr(), dict): + index = int(index) # TODO validation try: - return self._list()[index] - except IndexError: + return self._vattr()[index] + except LookupError: raise ItemNotFoundError(index) + @handler(u'Get information about all items') + def show(self): + r"show() -> list of items :: List all the complete items information." + if isinstance(self._attr(), dict): + return self._attr().values() + return self._vattr() + +class ListSubHandler(ContainerSubHandler): + r"""ListSubHandler(parent) -> ListSubHandler instance. + + ContainerSubHandler holding lists. See ComposedSubHandler documentation + for details. + """ + @handler(u'Get how many items are in the list') def len(self): r"len() -> int :: Get how many items are in the list." - return len(self._list()) + return len(self._vattr()) - @handler(u'Get information about all items') - def show(self): - r"show() -> list of Hosts :: List all the complete items information." - return self._list() - -class DictSubHandler(SubHandler): +class DictSubHandler(ContainerSubHandler): r"""DictSubHandler(parent) -> DictSubHandler instance. - This is a helper class to inherit from to automatically handle subcommands - that operates over a dict parent attribute. + ContainerSubHandler holding dicts. See ComposedSubHandler documentation + for details. + """ + + @handler(u'List all the items by key') + def list(self): + r"list() -> tuple :: List all the item keys." + return self._attr().keys() + +class ComposedSubHandler(SubHandler): + r"""ComposedSubHandler(parent) -> ComposedSubHandler instance. - The dict attribute to handle and the class of objects that it contains can - be defined by calling the constructor or in a more declarative way as - class attributes, like: + This is a helper class to implement ListComposedSubHandler and + DictComposedSubHandler. You should not use it directly. - class TestHandler(DictSubHandler): - _dict_subhandler_attr = 'some_dict' - _dict_subhandler_class = SomeClass + This class is usefull when you have a parent that has a dict (cont) + that stores some object that has an attribute (attr) with a list or + a dict of objects of some class. In that case, this class provides + automated commands to add, update, delete, get and show that objects. + This commands takes the cont (key of the dict for the object holding + the attr), and an index for access the object itself (in the attr + list/dict). - This way, the parent's some_dict attribute (self.parent.some_dict) will be - managed automatically, providing the commands: add, update, delete, get, - list and show. New items will be instances of SomeClass, which should - provide a constructor with at least the key value and an update() method, - if it should be possible to modify it. + The container object (cont) that holds a containers, the attribute of + that object that is the container itself, and the class of the objects + that it contains can be defined by calling the constructor or in a + more declarative way as class attributes, like: + + class TestHandler(ComposedSubHandler): + _comp_subhandler_cont = 'some_cont' + _comp_subhandler_attr = 'some_attr' + _comp_subhandler_class = SomeClass + + This way, the parent's some_cont attribute (self.parent.some_cont) + will be managed automatically, providing the commands: add, update, + delete, get and show for manipulating a particular instance that holds + of SomeClass. For example, updating an item at the index 5 is the same + (simplified) as doing parent.some_cont[cont][5].update(). + SomeClass should provide a cmp operator to see if the item is on the + container and an update() method, if it should be possible to modify + it. If SomeClass has an _add, _update or _delete attribute, it set + them to true when the item is added, updated or deleted respectively + (in case that it's deleted, it's not removed from the container, + but it's not listed either). If the container objects + (parent.some_cont[cont]) has an _update attribute, it's set to True + when any add, update or delete command is executed. """ - def __init__(self, parent, attr=None, cls=None): + def __init__(self, parent, cont=None, attr=None, cls=None): r"Initialize the object, see the class documentation for details." self.parent = parent + if cont is not None: + self._comp_subhandler_cont = cont if attr is not None: - self._dict_subhandler_attr = attr + self._comp_subhandler_attr = attr if cls is not None: - self._dict_subhandler_class = cls + self._comp_subhandler_class = cls + + def _cont(self): + return getattr(self.parent, self._comp_subhandler_cont) + + def _attr(self, cont, attr=None): + if attr is None: + return getattr(self._cont()[cont], self._comp_subhandler_attr) + setattr(self._cont()[cont], self._comp_subhandler_attr, attr) - def _dict(self): - return getattr(self.parent, self._dict_subhandler_attr) + def _vattr(self, cont): + if isinstance(self._attr(cont), dict): + return dict([(k, i) for (k, i) in self._attr(cont).items() + if not hasattr(i, '_delete') or not i._delete]) + return [i for i in self._attr(cont) + if not hasattr(i, '_delete') or not i._delete] @handler(u'Add a new item') - def add(self, key, *args, **kwargs): - r"add(key, ...) -> None :: Add an item to the dict." - item = self._dict_subhandler_class(key, *args, **kwargs) - if key in self._dict(): - raise ItemAlreadyExistsError(key) - self._dict()[key] = item + def add(self, cont, *args, **kwargs): + r"add(cont, ...) -> None :: Add an item to the list." + if not cont in self._cont(): + raise ContainerNotFoundError(cont) + item = self._comp_subhandler_class(*args, **kwargs) + if hasattr(item, '_add'): + item._add = True + key = item + if isinstance(self._attr(cont), dict): + key = item.as_tuple()[0] + # do we have the same item? then raise an error + if key in self._vattr(cont): + raise ItemAlreadyExistsError(item) + # do we have the same item, but logically deleted? then update flags + if key in self._attr(cont): + index = key + if not isinstance(self._attr(cont), dict): + index = self._attr(cont).index(item) + if hasattr(item, '_add'): + self._attr(cont)[index]._add = False + if hasattr(item, '_delete'): + self._attr(cont)[index]._delete = False + else: # it's *really* new + if isinstance(self._attr(cont), dict): + self._attr(cont)[key] = item + else: + self._attr(cont).append(item) + if hasattr(self._cont()[cont], '_update'): + self._cont()[cont]._update = True @handler(u'Update an item') - def update(self, key, *args, **kwargs): - r"update(key, ...) -> None :: Update an item of the dict." + def update(self, cont, index, *args, **kwargs): + r"update(cont, index, ...) -> None :: Update an item of the container." # TODO make it right with metaclasses, so the method is not created # unless the update() method really exists. - if not hasattr(self._dict_subhandler_class, 'update'): + # TODO check if the modified item is the same of an existing one + if not cont in self._cont(): + raise ContainerNotFoundError(cont) + if not isinstance(self._attr(cont), dict): + index = int(index) # TODO validation + if not hasattr(self._comp_subhandler_class, 'update'): raise CommandNotFoundError(('update',)) - if not key in self._dict(): - raise ItemNotFoundError(key) - self._dict()[key].update(*args, **kwargs) + try: + item = self._vattr(cont)[index] + item.update(*args, **kwargs) + if hasattr(item, '_update'): + item._update = True + if hasattr(self._cont()[cont], '_update'): + self._cont()[cont]._update = True + except LookupError: + raise ItemNotFoundError(index) @handler(u'Delete an item') - def delete(self, key): - r"delete(key) -> None :: Delete an item of the dict." - if not key in self._dict(): - raise ItemNotFoundError(key) - del self._dict()[key] + def delete(self, cont, index): + r"delete(cont, index) -> None :: Delete an item of the container." + if not cont in self._cont(): + raise ContainerNotFoundError(cont) + if not isinstance(self._attr(cont), dict): + index = int(index) # TODO validation + try: + item = self._vattr(cont)[index] + if hasattr(item, '_delete'): + item._delete = True + else: + del self._attr(cont)[index] + if hasattr(self._cont()[cont], '_update'): + self._cont()[cont]._update = True + return item + except LookupError: + raise ItemNotFoundError(index) - @handler(u'Get information about an item') - def get(self, key): - r"get(key) -> Host :: List all the information of an item." - if not key in self._dict(): - raise ItemNotFoundError(key) - return self._dict()[key] + @handler(u'Remove all items (use with care).') + def clear(self, cont): + r"clear(cont) -> None :: Delete all items of the container." + if not cont in self._cont(): + raise ContainerNotFoundError(cont) + if isinstance(self._attr(cont), dict): + self._attr(cont).clear() + else: + self._attr(cont, list()) - @handler(u'List all the items by key') - def list(self): - r"list() -> tuple :: List all the item keys." - return self._dict().keys() + @handler(u'Get information about an item') + def get(self, cont, index): + r"get(cont, index) -> item :: List all the information of an item." + if not cont in self._cont(): + raise ContainerNotFoundError(cont) + if not isinstance(self._attr(cont), dict): + index = int(index) # TODO validation + try: + return self._vattr(cont)[index] + except LookupError: + raise ItemNotFoundError(index) @handler(u'Get information about all items') - def show(self): - r"show() -> list of Hosts :: List all the complete items information." - return self._dict().values() + def show(self, cont): + r"show(cont) -> list of items :: List all the complete items information." + if not cont in self._cont(): + raise ContainerNotFoundError(cont) + if isinstance(self._attr(cont), dict): + return self._attr(cont).values() + return self._vattr(cont) + +class ListComposedSubHandler(ComposedSubHandler): + r"""ListComposedSubHandler(parent) -> ListComposedSubHandler instance. + + ComposedSubHandler holding lists. See ComposedSubHandler documentation + for details. + """ + + @handler(u'Get how many items are in the list') + def len(self, cont): + r"len(cont) -> int :: Get how many items are in the list." + if not cont in self._cont(): + raise ContainerNotFoundError(cont) + return len(self._vattr(cont)) + +class DictComposedSubHandler(ComposedSubHandler): + r"""DictComposedSubHandler(parent) -> DictComposedSubHandler instance. + + ComposedSubHandler holding dicts. See ComposedSubHandler documentation + for details. + """ + + @handler(u'List all the items by key') + def list(self, cont): + r"list(cont) -> tuple :: List all the item keys." + if not cont in self._cont(): + raise ContainerNotFoundError(cont) + return self._attr(cont).keys() if __name__ == '__main__':