taskflow/taskflow/examples/run_by_iter.py

85 lines
2.6 KiB
Python

# -*- coding: utf-8 -*-
# Copyright (C) 2014 Yahoo! Inc. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
import logging
import os
import sys
logging.basicConfig(level=logging.ERROR)
self_dir = os.path.abspath(os.path.dirname(__file__))
top_dir = os.path.abspath(os.path.join(os.path.dirname(__file__),
os.pardir,
os.pardir))
sys.path.insert(0, top_dir)
sys.path.insert(0, self_dir)
from taskflow import engines
from taskflow.patterns import linear_flow as lf
from taskflow import task
# INTRO: This example shows how to run a set of engines at the same time, each
# running in different engines using a single thread of control to iterate over
# each engine (which causes that engine to advanced to its next state during
# each iteration).
class EchoTask(task.Task):
def execute(self, value):
print(value)
return chr(ord(value) + 1)
def make_alphabet_flow(i):
f = lf.Flow("alphabet_%s" % (i))
start_value = 'A'
end_value = 'Z'
curr_value = start_value
while ord(curr_value) <= ord(end_value):
next_value = chr(ord(curr_value) + 1)
if curr_value != end_value:
f.add(EchoTask(name="echoer_%s" % curr_value,
rebind={'value': curr_value},
provides=next_value))
else:
f.add(EchoTask(name="echoer_%s" % curr_value,
rebind={'value': curr_value}))
curr_value = next_value
return f
# Adjust this number to change how many engines/flows run at once.
flow_count = 1
flows = []
for i in range(0, flow_count):
f = make_alphabet_flow(i + 1)
flows.append(make_alphabet_flow(i + 1))
engine_iters = []
for f in flows:
e = engines.load(f)
e.compile()
e.storage.inject({'A': 'A'})
e.prepare()
engine_iters.append(e.run_iter())
while engine_iters:
for it in list(engine_iters):
try:
print(next(it))
except StopIteration:
engine_iters.remove(it)