bumblebee-status/bumblebee/engine.py
Tobi-wan Kenobi f33711f49f [core] Pass configuration parameters to modules
User can now use -p <key>=<value> to pass configuration parameters to
modules. For this, the module gets a "parameter()" method. Parameter
keys are in the format <name>.<key> where <name> is the name of the
loaded module. This is either the name of the module itself (e.g. "cpu")
or its alias, if the user specified it, for example:

bumblebee-status -m cpu -p cpu.warning=90

vs.

bumblebee-status -m cpu:test -p test.warning=90

see #23
2016-12-09 08:00:26 +01:00

108 lines
3.3 KiB
Python

"""Core application engine"""
import os
import time
import pkgutil
import importlib
import bumblebee.error
import bumblebee.modules
def modules():
"""Return a list of available modules"""
result = []
path = os.path.dirname(bumblebee.modules.__file__)
for mod in [name for _, name, _ in pkgutil.iter_modules([path])]:
result.append({
"name": mod
})
return result
class Module(object):
"""Module instance base class
Objects of this type represent the modules that
the user configures. Concrete module implementations
(e.g. CPU utilization, disk usage, etc.) derive from
this base class.
"""
def __init__(self, engine, widgets):
self.name = self.__module__.split(".")[-1]
self._widgets = []
if widgets:
self._widgets = widgets if isinstance(widgets, list) else [widgets]
def widgets(self):
"""Return the widgets to draw for this module"""
return self._widgets
def update(self, widgets):
"""By default, update() is a NOP"""
pass
def parameter(self, name, default=None):
"""Return the config parameter 'name' for this module"""
name = "{}.{}".format(self._config_name, name)
return self._config.get(name, default)
def set_config(self, config, name):
"""Set the config for this module"""
self._config = config
self._config_name = name
class Engine(object):
"""Engine for driving the application
This class connects input/output, instantiates all
required modules and drives the "event loop"
"""
def __init__(self, config, output=None):
self._output = output
self._config = config
self._running = True
self._modules = []
self.load_modules(config.modules())
def load_modules(self, modules):
"""Load specified modules and return them as list"""
for module in modules:
self._modules.append(self.load_module(module["module"], module["name"]))
return self._modules
def load_module(self, module_name, config_name=None):
"""Load specified module and return it as object"""
if config_name == None:
config_name = module_name
try:
module = importlib.import_module("bumblebee.modules.{}".format(module_name))
except ImportError as error:
raise bumblebee.error.ModuleLoadError(error)
res = getattr(module, "Module")(self)
res.set_config(self._config, config_name)
return res
def running(self):
"""Check whether the event loop is running"""
return self._running
def stop(self):
"""Stop the event loop"""
self._running = False
def run(self):
"""Start the event loop"""
self._output.start()
while self.running():
self._output.begin()
for module in self._modules:
module.update(module.widgets())
for widget in module.widgets():
widget.set_module(module)
self._output.draw(widget=widget, engine=self)
self._output.flush()
self._output.end()
if self.running():
time.sleep(1)
self._output.stop()
# vim: tabstop=8 expandtab shiftwidth=4 softtabstop=4