def _serialize_object(obj, cd: set = None):
""" Given an arbitraty Python object creates a tuple (ClassName, {Fields}).
A fair effort is made to avoid infinite recursion on cyclic objects.
:param obj: Arbitrary object to encode
:param cd: A set with ids of object, for cycle detection
:return: A 2-tuple ((ClassName, {Fields}) or None, CycleDetect value)
"""
if cd is None:
cd = set()
# if cyclic encoding detected, ignore this value
if id(obj) in cd:
return None, cd
cd.add(id(obj))
object_name = type(obj).__name__
fields = {}
for key in dir(obj):
val = getattr(obj, key)
if not callable(val) and not key.startswith("_"):
if _is_a_simple_object(val):
fields[term.Atom(key)] = val
else:
(ser, cd) = _serialize_object(val, cd=cd)
fields[term.Atom(key)] = ser
return (term.Atom(object_name), fields), cd
def convert_to_erlang_type(x):
if isinstance(x, str):
return term.Binary(x.encode('utf-8'))
elif isinstance(x, bytes):
return term.Binary(x)
elif isinstance(x, list) or isinstance(x, set):
new_value = term.List()
for e in x:
new_value.append(convert_to_erlang_type(e))
return new_value
elif isinstance(x, tuple):
new_value = ()
for e in x:
new_value = new_value + (convert_to_erlang_type(e), )
return new_value
elif isinstance(x, dict):
new_value = {}
for k, v in x:
new_value[convert_to_erlang_type(k)] = convert_to_erlang_type(v)
return new_value
elif isinstance(x, bool):
if x:
return term.Atom('true')
else:
return term.Atom('false')
else:
return x
def test_encode_atom(self):
""" Try an atom 'hello' """
data1 = etf.term_to_binary(term.Atom('hello', encoding="latin-1"))
expected1 = bytes([131, ord('d'), 0, 5, 104, 101, 108, 108, 111])
self.assertEqual(data1, expected1)
data2 = etf.term_to_binary(term.Atom('hello', encoding="utf8"))
expected2 = bytes([131, ord('v'), 0, 5, 104, 101, 108, 108, 111])
self.assertEqual(data2, expected2)
def load(self, namebin, codebin, configbin):
try:
dynamic_function_name = namebin.bytes_.decode('utf-8')
self.logger.debug('loading {0}'.format(dynamic_function_name))
code = codebin.bytes_.decode('utf-8')
config = configbin.bytes_.decode('utf-8')
c = compile(code, '<string>', 'exec')
if config:
json_config = json.loads(config)
else:
json_config = {}
code_locals = {}
# workaround for numpy (PATH not in environ)
# https://github.com/numpy/numpy/issues/10338
# https://stackoverflow.com/questions/48168482/keyerror-path-on-numpy-import
exec(
compile("import os; os.environ.setdefault('PATH', '')",
'<string>', 'exec'), code_locals, code_locals)
exec(c, code_locals, code_locals)
#sys.stderr.write('code_locals = ' + str(code_locals))
code_locals['_get_config'] = lambda: json_config
# lets find out whether the function (with given name) exists
# in the code and also its arity (that is its number of parameters)
if ('main' in code_locals) and callable(code_locals['main']):
sig = signature(code_locals['main'])
function_arity = len(sig.parameters)
# copy locals to globals because otherwise
# eval('..', globals, locals) will fail since
# the depending functions will not be available in globals
full_function_name = dynamic_function_name + '/' + str(
function_arity)
self.dynamic_functions[full_function_name] = (
code_locals, hash(codebin.bytes_), hash(configbin.bytes_))
self.logger.debug(' saved = ' + str(self.dynamic_functions))
return (term.Atom('ok'), function_arity)
else:
# the code compiled but function do not exist
return (term.Atom('error'), term.Atom('not_found'))
except Exception as e:
print(traceback.format_exception(None, e, e.__traceback__),
file=sys.stderr,
flush=True)
return erlang_error(str(e))
def handle_one_inbox_message(self, msg) -> None:
gencall = gen.parse_gen_message(msg)
if isinstance(gencall, str):
self.logger.debug("MyProcess: {0}".format(gencall))
return
# Handle the message in 'gencall' using its sender_, ref_ and
# message_ fields
if True:
# gencall is of type gen.GenIncomingMessage
if type(gencall.message_) != tuple or len(gencall.message_) != 3:
error_message = "Only {M :: binary(), F :: binary(), Args :: tuple()} messages allowed"
gencall.reply(local_pid=self.pid_,
result=erlang_error(error_message))
else:
(module, function, arguments) = gencall.message_
module_name = module.bytes_.decode('utf-8')
function_name = function.bytes_.decode('utf-8')
self.logger.debug('{0}.{1}({2})'.format(
module_name, function_name, arguments))
try:
if module_name == 'MyProcess' and function_name == 'load':
result = self.load(*arguments)
elif module_name == 'MyProcess' and function_name == 'eval':
result = self.evaluate(*arguments)
elif module_name == 'MyProcess' and function_name == 'invoke':
result = self.invoke_main(*arguments)
elif module_name == 'MyProcess' and function_name == 'invoke_simple_http':
result = self.invoke_simple_http(*arguments)
else:
# DONT allow generic calls directly, instead
# let user define dynamic functions and then within
# that call those functions if required
#fun_ref = eval(module_name + '.' + function_name,
# self.code_globals,
# self.code_locals)
#result = fun_ref(*arguments)
result = erlang_error('only dynamic calls allowed')
except Exception as e:
print(traceback.format_exception(None, e, e.__traceback__),
file=sys.stderr,
flush=True)
result = erlang_error(str(e))
# flush stdout and err so that peer can read latest values
# if listening on the same
sys.stdout.flush()
sys.stderr.flush()
# Send a reply
gencall.reply(local_pid=self.pid_, result=result)
else:
# Send an error exception which will crash Erlang caller
gencall.reply_exit(local_pid=self.pid_, reason=term.Atom('error'))
def handle_one_inbox_message(self, msg):
gencall = gen.parse_gen_message(msg)
if not isinstance(gencall, gen.GenIncomingMessage):
print("NetKernel:", gencall)
return
# Incoming gen_call packet to net_kernel, might be that net_adm:ping
msg = gencall.message_
if isinstance(msg[0], term.Atom) and msg[0].text_ == 'is_auth':
gencall.reply(local_pid=self.pid_, result=term.Atom('yes'))
else:
print("NetKernel: unknown message", msg)
def _bytes_to_atom(name: bytes, encoding: str, options: dict):
""" Recognize familiar atom values. """
if name == b'true':
return True
if name == b'false':
return False
if name == b'undefined':
return None
if options.get("atoms_as_strings", False):
return name.decode(encoding)
return term.Atom(text=name.decode(encoding), encoding=encoding)
def _control_term_send(from_pid, dst):
if isinstance(dst, term.Atom):
return CONTROL_TERM_REG_SEND, from_pid, term.Atom(''), dst
else:
return CONTROL_TERM_SEND, term.Atom(''), dst
def __init__(self, node: Node) -> None:
Process.__init__(self, node)
node.register_name(self, term.Atom('net_kernel'))
def __init__(self, node, logger) -> None:
Process.__init__(self, node)
node.register_name(self, term.Atom('pythonserver'))
self.logger = logger
self.dynamic_functions = {}
def erlang_error(msg: str):
return (term.Atom('error'), term.Binary(msg.encode('utf-8')))
def invoke(self, entry_fname, namebin, codebin, configbin, arguments):
"""entry_fname is either 'main' or 'handle_event'"""
try:
name = namebin.bytes_.decode('utf-8')
if not isinstance(arguments, tuple):
raise Exception('Arguments must be a tuple but is ' +
str(type(arguments)))
self.logger.debug(' retrieved = ' + str(self.dynamic_functions))
name_with_arity = name + '/' + str(len(arguments))
if name_with_arity not in self.dynamic_functions:
# lazy load the function and compile it
load_result = self.load(namebin, codebin, configbin)
if load_result[0] != term.Atom('ok'):
return load_result
entry = self.dynamic_functions[name_with_arity]
else:
entry = self.dynamic_functions[name_with_arity]
stored_code_hash = entry[1]
if hash(codebin.bytes_) != stored_code_hash:
# compile and save the function because
# the hashes do not match
load_result = self.load(namebin, codebin, configbin)
if load_result[0] != term.Atom('ok'):
return load_result
# re-assign entry to updated one
entry = self.dynamic_functions[name_with_arity]
stored_config_hash = entry[2]
if hash(configbin.bytes_) != stored_config_hash:
config = configbin.bytes_.decode('utf-8')
if config:
json_config = json.loads(config)
else:
json_config = {}
entry[0]['_get_config'] = lambda: json_config
self.dynamic_functions[name_with_arity] = (
entry[0], entry[1], hash(configbin.bytes_))
entry = self.dynamic_functions[name_with_arity]
code_locals = entry[0]
if (entry_fname in code_locals) and (callable(
code_locals[entry_fname])):
main_fun = code_locals[entry_fname]
self.logger.info('main_fun = {0}'.format(main_fun))
if inspect.isfunction(main_fun):
sig = signature(main_fun)
main_fun_arity = len(sig.parameters)
if main_fun_arity == len(arguments):
# without promoting locals to temporary globals
# the import statements do not work
call_arguments = []
for i in range(0, len(arguments)):
argname = 'arg' + str(i) + '__'
# save arguments to code_locals
code_locals[argname] = arguments[i]
call_arguments.append(argname)
call_command = \
entry_fname + '(' \
+ ','.join(call_arguments) \
+ ')'
self.logger.info(
'call_command, = {0}'.format(call_command))
eval_result = eval(call_command, code_locals,
code_locals)
self.logger.debug('response = {0}'.format(eval_result))
result = convert_to_erlang_type(eval_result)
# cleanup code_locals to save memory
for i in range(0, len(arguments)):
argname = 'arg' + str(i) + '__'
del code_locals[argname]
# send back the result
if is_valid_erlang_type(result):
return result
else:
return erlang_error(
"Invalid result type = {}".format(
type(result)))
else:
return erlang_error(
'{0}.{1} takes {2} arguments only'.format(
name, entry_fname, main_fun_arity))
return erlang_error('Missing function {0}.{1}().'.format(
name, entry_fname))
except Exception as e:
print(traceback.format_exception(None, e, e.__traceback__),
file=sys.stderr,
flush=True)
return erlang_error(str(e))
def __init__(self, node: Node) -> None:
Process.__init__(self, node)
node.register_name(self, term.Atom('rex'))
self.traceback_depth_ = 5
""" This being non-zero enables formatting exception tracebacks with the