def execute_hooks(event_name, *args, **kwargs):
"""Execute action hooks based upon parent task state.
"""
# skip tasks that aren't part of pipeline
if not isinstance(kwargs['sender'], PipelineTask):
return
task_kwargs = deepcopy(kwargs['kwargs']) # inception!
state = task_kwargs.get('_pipeline_chain_state', {})
if 'hooks' in state:
hooks = [
h for h in state['hooks'] if \
h.event == event_name
]
if not hooks:
return []
logger.debug('task has hooks: {}'.format(hooks))
context = task_kwargs['_pipeline_chain_state']['build_context']
callbacks = []
for hook in hooks:
try:
should_execute = safe_eval(
hook.predicate,
context.eval_context
)
except:
should_execute = False
if should_execute:
source = kwargs['args'][0] # wtf
callbacks.append(hook.task_action.prepare(source, context))
else:
logger.debug('hook {} should not execute.'.format(hook.task_action))
if len(callbacks):
logger.debug('Executing some hooks: {}'.format(callbacks))
canvas = group(*callbacks)
return canvas.apply_async()
return []
def evaluate(self, expression):
"""Evaluate an expression using context.
"""
return safe_eval(expression, self.eval_context)