X-Git-Url: https://git.llucax.com/software/pymin.git/blobdiff_plain/066b7ef8b45149aec09d41ca74b08d0b8711cb13..8ef5c142a621796d24b474e39eb0c20989bfdf6f:/pymin/services/util.py diff --git a/pymin/services/util.py b/pymin/services/util.py index 2fe7f9b..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', 'RestartHandler', 'ReloadHandler', '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""" @@ -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, @@ -703,7 +744,7 @@ class ContainerSubHandler(SubHandler): item.update(*args, **kwargs) if hasattr(item, '_update'): item._update = True - except IndexError: + except LookupError: raise ItemNotFoundError(index) @handler(u'Delete an item') @@ -718,11 +759,12 @@ class ContainerSubHandler(SubHandler): else: del self._attr()[index] return item - except IndexError: + 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: @@ -735,7 +777,7 @@ class ContainerSubHandler(SubHandler): index = int(index) # TODO validation try: return self._vattr()[index] - except IndexError: + except LookupError: raise ItemNotFoundError(index) @handler(u'Get information about all items') @@ -748,25 +790,8 @@ class ContainerSubHandler(SubHandler): class ListSubHandler(ContainerSubHandler): 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): - _cont_subhandler_attr = 'some_list' - _cont_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. 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 list, but it's not listed either). + ContainerSubHandler holding lists. See ComposedSubHandler documentation + for details. """ @handler(u'Get how many items are in the list') @@ -777,32 +802,209 @@ class ListSubHandler(ContainerSubHandler): 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() - 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: +class ComposedSubHandler(SubHandler): + r"""ComposedSubHandler(parent) -> ComposedSubHandler instance. - class TestHandler(DictSubHandler): - _cont_subhandler_attr = 'some_dict' - _cont_subhandler_class = SomeClass + This is a helper class to implement ListComposedSubHandler and + DictComposedSubHandler. You should not use it directly. + + 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, an as_tuple() method - and an update() method, if it should be possible to modify + 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 dict, but it's - not listed either). + (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, 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._comp_subhandler_attr = attr + if cls is not None: + 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 _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, 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, 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. + # 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',)) + 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, 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'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'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, 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): - r"list() -> tuple :: List all the item keys." - return self._attr().keys() + 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__':