multi-tasks
Install:
npm install multi-tasks
How to use:
//see examples/example0
let multiTasks = require('multi-tasks').multiTasks;
//Step1, if you have tasks that need to be executed simultaneously,
// provide them as an array, multi-tasks will automatically split them and execute.
let alltasks = [];
for(let i=0;i<50;i++){
alltasks.push({
name: `task-${i}`,
data: `This prop is for a subtask`
});
};
//Step2, provide a function to process a certain sub-task and return the result data
let processTask = (task, helper)=>{
let {taskCount} = task;
return 'a result which is not a promise';
};
//Step3, run!
multiTasks({
initialTasks: alltasks,
processTask,
taskRootFolder: `../examples-tmp-data/example0`, //a directory to store progress and results files, you can check the progress here
taskId: 'my-task',
numberOfWorkers: 3, //how many workers are working in parallel
//autoCloseAfterCompletion: true, //if you have dynamically generated new tasks, put this as false
shouldTerminate:(info)=>{
//return true if you need to terminate the whole process
},
onFinish: (report)=>{
console.log('finish callback', report);
}
});
Have a try:
node examples/example0/run
node examples/example1/run
More about the task processing function
//Example1, return a promise for async processes,
// you can return a promise or a non-promise result,
// all result data can be found in the results/succ folder
let processTask = (task, helper)=>{
let {taskCount} = task;
return new Promise((resolve, reject)=>{
resolve({
data:`task${taskCount} complete`
})
})
};
//Example2, dynamically create a new task while processing
let processTask = (task, helper)=>{
let {taskCount} = task;
if(taskCount % 2 === 0){
//create a new task if needed
helper.createNewTasks({
msg:'a new task'
});
return;
}
return new Promise((resolve, reject)=>{
resolve({
data:`task${taskCount} complete`
})
})
};
//Example3, generate/throw exceptions in a task method
let processTask = (task, helper)=>{
let {taskCount} = task;
//This is the demo of exceptions/errors, they will be captured and saved in the results/errors folder
if(taskCount===3) throw 'exception';
if(taskCount===4) return Promise.reject({err:'a test error'});//use Promise.reject method
if(taskCount===5) aaa = bbb;//this undefined exception will be captured by multi-tasks
return {data:'succ'};
}
Changelog:
- 2.0.9 Update readme examples
- 2.0.8 Update readme examples
- 2.0.7 Update changelog
- 2.0.6 Update readme, remove failed examples
- 2.0.5 Update readme examples
- 2.0.4 Support resume from a failed task
- 2.0.3 Fix: mkdir bug on windows
- 2.0.2 new feature: support shouldTerminate
- 2.0.1 Avoid possible I/O conflicts.
- 2.0.0 Rewritten with a new architecture to support dynamic tasks.
- 1.2.8 Fix: create task folder failed on MacOS
- 1.2.7 Small updates
- 1.2.6 Support onFinish event
- 1.2.5 Rename numberOfWorks to numberOfWorkers, the old one are still supported ;-)
- 1.2.4 Fix: opt.numberOfWorkers not work
- 1.2.3 Update README
- 1.2.2 Update README and examples
- 1.2.1 Handle exceptions and errors in subtasks
- 1.2.0 Simplified usage by providing the function way and support return Promise
- 1.1.4 Remove make-dir
- 1.1.3 Simplified usage, see example0
- 1.1.2
- 1.1.1 Rename files, updated changelog
- 1.1.0 Simplified the usage of a customized Consumer, see example0
- 1.0.8 Fix examples
- 1.0.7 Remove moment
- 1.0.6 Performance optimization
Github: