asynctasks

Task scheduler based on asyncio. Allows max-concurrency and granularity to be specified. Execution results are printed as a Gantt chart.

Sample Usage

from asynctasks.executor import Executor
from asynctasks.executionplan import ExecutionPlan
import asyncio

#create an array of tasks
tasks_dict_array = [{"dependencies": [], "name": "task0"}, {"dependencies": [0], "name": "task1"},
                        {"dependencies": [1], "name": "task2"}, {"dependencies": [0], "name": "task3"},
                        {"dependencies": [], "name": "task4"}, {"dependencies": [], "name": "task5"}]

#define an async function that should be executed for each task
async def print_task(loop, task):
   print("Executing task {}".format(task))
   await asyncio.sleep(0.1)

#create an execution plan for the tasks
plan = ExecutionPlan().from_dict_array(tasks_dict_array)
print("\nBEFORE EXECUTION\n{}".format(plan))

#execute the plan with print_task function and max_concurrency as 2
Executor(plan, 2, 0.01, print_task).trigger_execution()
print("\nAFTER EXECUTION\n{}".format(plan.as_gantt()))

Sample Output

BEFORE EXECUTION
task0 Ready
    task1
        task2
    task3
task4 Ready
task5 Ready

Executing task {'dependencies': [], 'name': 'task0', 'start_time': 1497528994.1246588}
Executing task {'dependencies': [], 'name': 'task4', 'start_time': 1497528994.1246588}
Executing task {'dependencies': [0], 'name': 'task1', 'start_time': 1497528994.236074}
Executing task {'dependencies': [0], 'name': 'task3', 'start_time': 1497528994.2370954}
Executing task {'dependencies': [1], 'name': 'task2', 'start_time': 1497528994.340769}
Executing task {'dependencies': [], 'name': 'task5', 'start_time': 1497528994.3417716}

AFTER EXECUTION
      ....................................................................................................
task0 ...............................
task1                                   .............................
task2                                                                    ................................
task3                                    .............................
task4 ...............................
task5                                                                     ...............................