osbrain.core — osBrain core logic

Core agent classes.

class osbrain.core.Agent(name=None, host=None)

Bases: object

A base agent class which is to be served by an AgentProcess.

An AgentProcess runs a Pyro multiplexed server and serves one Agent object.

Parameters:

name : str, default is None

Name of the Agent.

host : str, default is None

Host address where the agent will bind to. When not set, ‘127.0.0.1’ (localhost) is used.

Attributes:

name : str

Name of the agent.

host : str

Host address where the agent is binding to.

socket : dict

A dictionary in which the key is the address or the alias and the value is the actual socket.

adddress : dict

A dictionary in which the key is the alias and the value is the actual address.

handler : dict

A dictionary in which the key is the socket and the values are the handlers for each socket.

poll_timeout : int

Polling timeout, in milliseconds. After this timeout, if no message is received, the agent executes de iddle() method before going back to polling.

keep_alive : bool

When set to True, the agent will continue executing the main loop.

running : bool

Set to True if the agent is running (executing the main loop).

Methods

addr(alias)	Parameters:
bind(kind[, alias, handler, host, port])	Bind to an agent address.
connect(server_address[, alias, handler])	Connect to a server agent address.
each(period, method, *args[, alias])	Execute a repeated action with a defined period.
handle_loopback(message)	Handle incoming messages in the loopback socket.
iddle()	This function is to be executed when the agent is iddle.
iterate()	Agent’s main iteration.
list_timers()	Returns:
log_debug(message[, logger])	Log a debug message.
log_error(message[, logger])	Log an error message.
log_info(message[, logger])	Log an info message.
log_warning(message[, logger])	Log a warning message.
loop()	Agent’s main loop.
loopback(header[, data])	Send a message to the loopback socket.
on_init()	This user-defined method is to be executed after initialization.
ping()	A simple ping method testing purposes.
raise_exception()	Raise an exception (for testing purposes).
run()	Run the agent.
safe(method, *args, **kwargs)	A safe call to a method.
safe_ping()	A simple loopback ping for testing purposes.
set_attr(**kwargs)	Set object attributes.
set_logger(logger[, alias])	Connect the agent to a logger and start logging messages to it.
set_loop(loop)
set_method(*args, **kwargs)	Set object methods.
stop()	Stop the agent.
stop_all_timers()	Stop all currently running timers.
stop_timer(alias)	Stop a currently running timer.
subscribe(alias, handlers)	Subscribe the agent to another agent.
test()	A test method to check the readiness of the agent.

close_sockets
execute
get_attr
kill
recv
register
registered
self_execute
send
send_recv
set_handler
shutdown
str2bytes

addr(alias)

Parameters:

alias : str

Alias of the socket whose address is to be retreived.

Returns:

AgentAddress

Address of the agent socket associated with the alias.

bind(kind, alias=None, handler=None, host=None, port=None)

Bind to an agent address.

Parameters:

kind : str, AgentAddressKind

The agent address kind: PUB, REQ…

alias : str, default is None

Optional alias for the socket.

handler, default is None

If the socket receives input messages, the handler/s is/are to be set with this parameter.

host : str, default is None

The host to bind to, when not given self.host is taken as default.

port : int, default is None

An optional port number. If not set, a random port is used for binding.

close_sockets()

connect(server_address, alias=None, handler=None)

Connect to a server agent address.

Parameters:

server_address : AgentAddress

Agent address to connect to.

alias : str, default is None

Optional alias for the new address.

handler, default is None

If the new socket receives input messages, the handler/s is/are to be set with this parameter.

each(period, method, *args, alias=None, **kwargs)

Execute a repeated action with a defined period.

Parameters:

period : float

Repeat the action execution with a delay of period seconds between executions.

method

Method (action) to be executed by the agent.

alias : str, default is None

An alias for the generated timer.

*args : tuple

Parameters to pass for the method execution.

**kwargs : dict

Named parameters to pass for the method execution.

Returns:

str

The timer alias or identifier.

execute(function, *args, **kwargs)

get_attr(name)

handle_loopback(message)

Handle incoming messages in the loopback socket.

iddle()

This function is to be executed when the agent is iddle.

After a timeout occurs when the agent’s poller receives no data in any of its sockets, the agent may execute this function.

iterate()

Agent’s main iteration.

This iteration is normally executed inside the main loop.

The agent is polling all its sockets for input data. It will wait for poll_timeout; after this period, the method iddle will be executed before polling again.

Returns:

int

1 if an error occurred during the iteration (we would expect this to happen if an interruption occurs during polling).

0 otherwise.

kill()

list_timers()

Returns:

list (str)

A list with all the timer aliases currently running.

log_debug(message, logger='_logger')

Log a debug message.

Parameters:

message : str

Message to log.

logger : str

Alias of the logger.

log_error(message, logger='_logger')

Log an error message.

Parameters:

message : str

Message to log.

logger : str

Alias of the logger.

log_info(message, logger='_logger')

Log an info message.

Parameters:

message : str

Message to log.

logger : str

Alias of the logger.

log_warning(message, logger='_logger')

Log a warning message.

Parameters:

message : str

Message to log.

logger : str

Alias of the logger.

loop()

Agent’s main loop.

This loop is executed until the keep_alive attribute is False or until an error occurs.

loopback(header, data=None)

Send a message to the loopback socket.

on_init()

This user-defined method is to be executed after initialization.

ping()

A simple ping method testing purposes.

raise_exception()

Raise an exception (for testing purposes).

recv(address)

register(socket, address, alias=None, handler=None)

registered(address)

run()

Run the agent.

safe(method, *args, **kwargs)

A safe call to a method.

A safe call is simply sent to be executed by the main thread.

Parameters:

method : str

Method name to be executed by the main thread.

*args : arguments

Method arguments.

*kwargs : keyword arguments

Method keyword arguments.

safe_ping()

A simple loopback ping for testing purposes.

self_execute(function, *args, **kwargs)

send(address, message, topic='')

send_recv(address, message)

set_attr(**kwargs)

Set object attributes.

Parameters:

kwargs : [name, value]

Keyword arguments will be used to set the object attributes.

set_handler(socket, handler)

set_logger(logger, alias='_logger')

Connect the agent to a logger and start logging messages to it.

set_loop(loop)

set_method(*args, **kwargs)

Set object methods.

Parameters:

args : [function]

New methods will be created for each function, taking the same name as the original function.

kwargs : [name, function]

New methods will be created for each function, taking the name specified by the parameter.

Returns:

str

Name of the registered method in the agent.

shutdown()

stop()

Stop the agent. Agent will stop running.

stop_all_timers()

Stop all currently running timers.

stop_timer(alias)

Stop a currently running timer.

Parameters:

alias : str

The alias or identifier of the timer.

str2bytes(message)

subscribe(alias, handlers)

Subscribe the agent to another agent.

Parameters:

alias : str

Alias of the new subscriber socket.

handlers : dict

A dictionary in which the keys represent the different topics and the values the actual handlers. If ,instead of a dictionary, a single handler is given, it will be used to subscribe the agent to any topic.

test()

A test method to check the readiness of the agent. Used for testing purposes, where timing is very important. Do not remove.

class osbrain.core.AgentProcess(name, nsaddr=None, addr=None, base=<class 'osbrain.core.Agent'>)

Bases: multiprocessing.context.Process

Agent class. Instances of an Agent are system processes which can be run independently.

Attributes:

authkey

daemon

Return whether process is a daemon

exitcode

Return exit code of process or None if it has yet to stop

ident

Return identifier (PID) of process or None if it has yet to start

name

pid

Return identifier (PID) of process or None if it has yet to start

sentinel

Return a file descriptor (Unix) or handle (Windows) suitable for waiting for process termination.

Methods

is_alive()	Return whether process is alive
join([timeout])	Wait until child process terminates
run()	Method to be run in sub-process; can be overridden in sub-class
sigint_handler(signal, frame)	Handle interruption signals.
start()	Start child process
terminate()	Terminate process; sends SIGTERM signal or uses TerminateProcess()

kill

kill()

run()

Method to be run in sub-process; can be overridden in sub-class

sigint_handler(signal, frame)

Handle interruption signals.

start()

Start child process

osbrain.core.run_agent(name, nsaddr=None, addr=None, base=<class 'osbrain.core.Agent'>)

Ease the agent creation process.

This function will create a new agent, start the process and then run its main loop through a proxy.

Parameters:

name : str

Agent name or alias.

nsaddr : SocketAddress, default is None

Name server address.

addr : SocketAddress, default is None

New agent address, if it is to be fixed.

Returns:

proxy

A proxy to the new agent.