[repo] Add a publish/subscribe mechanism for inter-instance communication using zmq
Each repo can have a publishing and any number of subscribing sockets
whose addresses are specified in the instance's configuration. An
application or cube can subscribe to some 'topics', and give a callback
that gets called when a message matching that topic is received.
As a proof of concept, this introduces a hook to clean up the caches
associated with the repository when an entity is deleted.
A subscription is added using Repository::zmq::add_subscription;
the callback receives a list representing the received multi-part
message as argument (the first element of the message is its topic).
"""https://pastebin.logilab.fr/show/860/"""
from logilab.astng import MANAGER, nodes, scoped_nodes
from logilab.astng.builder import ASTNGBuilder
def turn_function_to_class(node):
"""turn a Function node into a Class node (in-place)"""
node.__class__ = scoped_nodes.Class
node.bases = ()
# remove return nodes so that we don't get warned about 'return outside
# function' by pylint
for rnode in node.nodes_of_class(nodes.Return):
rnode.parent.body.remove(rnode)
# that seems to be enough :)
def cubicweb_transform(module):
# handle objectify_predicate decorator (and its former name until bw compat
# is kept). Only look at module level functions, should be enough.
for assnodes in module.locals.values():
for node in assnodes:
if isinstance(node, scoped_nodes.Function) and node.decorators:
for decorator in node.decorators.nodes:
for infered in decorator.infer():
if infered.name in ('objectify_predicate', 'objectify_selector'):
turn_function_to_class(node)
break
else:
continue
break
# add yams base types into 'yams.buildobjs', astng doesn't grasp globals()
# magic in there
if module.name == 'yams.buildobjs':
from yams import BASE_TYPES
for etype in BASE_TYPES:
module.locals[etype] = [scoped_nodes.Class(etype, None)]
# add data() to uiprops module
if module.name.endswith('.uiprops'):
fake = ASTNGBuilder(MANAGER).string_build('''
def data(string):
return u''
''')
module.locals['data'] = fake.locals['data']
def register(linter):
"""called when loaded by pylint --load-plugins, nothing to do here"""
MANAGER.register_transformer(cubicweb_transform)