platypush/platypush/utils/__init__.py
2018-09-20 10:49:57 +00:00

124 lines
3.3 KiB
Python

import ast
import errno
import hashlib
import importlib
import inspect
import logging
import os
import signal
logger = logging.getLogger(__name__)
def get_module_and_method_from_action(action):
""" Input : action=music.mpd.play
Output : ('music.mpd', 'play') """
tokens = action.split('.')
module_name = str.join('.', tokens[:-1])
method_name = tokens[-1:][0]
return (module_name, method_name)
def get_message_class_by_type(msgtype):
""" Gets the class of a message type given as string """
try:
module = importlib.import_module('platypush.message.' + msgtype)
except ImportError as e:
logger.warning('Unsupported message type {}'.format(msgtype))
raise RuntimeError(e)
cls_name = msgtype[0].upper() + msgtype[1:]
try:
msgclass = getattr(module, cls_name)
except AttributeError as e:
logger.warning('No such class in {}: {}'.format(
module.__name__, cls_name))
raise RuntimeError(e)
return msgclass
def get_event_class_by_type(type):
""" Gets an event class by type name """
event_module = importlib.import_module('.'.join(type.split('.')[:-1]))
return getattr(event_module, type.split('.')[-1])
def set_timeout(seconds, on_timeout):
"""
Set a function to be called if timeout expires without being cleared.
It only works on the main thread.
Params:
seconds -- Timeout in seconds
on_timeout -- Function invoked on timeout unless clear_timeout is called before
"""
def _sighandler(signum, frame):
on_timeout()
signal.signal(signal.SIGALRM, _sighandler)
signal.alarm(seconds)
def clear_timeout():
""" Clear any previously set timeout """
signal.alarm(0)
def get_hash(s):
""" Get the SHA256 hash hexdigest of a string input """
return hashlib.sha256(s.encode('utf-8')).hexdigest()
def get_decorators(cls, climb_class_hierarchy=False):
"""
Get the decorators of a class as a {"decorator_name": [list of methods]} dictionary
:param climb_class_hierarchy: If set to True (default: False), it will search return the decorators in the parent classes as well
:type climb_class_hierarchy: bool
"""
decorators = {}
def visit_FunctionDef(node):
for n in node.decorator_list:
name = ''
if isinstance(n, ast.Call):
name = n.func.attr if isinstance(n.func, ast.Attribute) else n.func.id
else:
name = n.attr if isinstance(n, ast.Attribute) else n.id
decorators[name] = decorators.get(name, set())
decorators[name].add(node.name)
if climb_class_hierarchy:
targets = inspect.getmro(cls)
else:
targets = [cls]
node_iter = ast.NodeVisitor()
node_iter.visit_FunctionDef = visit_FunctionDef
for target in targets:
try:
node_iter.visit(ast.parse(inspect.getsource(target)))
except TypeError:
# Ignore built-in classes
pass
return decorators
def get_redis_queue_name_by_message(msg):
from platypush.message import Message
if not isinstance(msg, Message):
logger.warning('Not a valid message (type: {}): {}'.format(type(msg), msg))
return 'platypush/responses/{}'.format(msg.id) if msg.id else None
# vim:sw=4:ts=4:et: