node-job-manager
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JobManager is a multipurpose, flexible, asynchronous task runner class written in Node.js.

Overview
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### A JobManager instance need the following informations to get started. they are
* ```workers```: An array of worker instances that are used to do the work.
* ```onLoadMore```: A function that tells how to retrieve tasks that need to processed with workers.
* ```work```: a function that does the real task. It is called with following syntax: worker( task, worker, cb ). task and worker are are belongs to the available tasks and workers. cb is the callback function that should be called after work is done.
* ```onError```: A function that is called when a Error is occurred during 'work' function. it is called with following syntax: onError(err, task, worker);
* ```onStopped```: A function that is called when all tasks are processed.


### JobManager instance is controlled by the following configuration options
* ```concurrency```: An integer that tells how many workers should be run a time. Note that, concurrency cab be higher than no.of workers. In this case, one worker may be used to process more than one task at a time.
* ```minConcurrency```: An integer. concurrency can not be decreased below this value.
* ```notifyAt```: if ( no.tasks/concurrency < notifyAt ), onLoadMore function is called to fetch more tasks.
* ```endReached```: A Boolean. if it is set to true, onLoadMore will not be called further. and thus, execution of JobManager will stop after processing all the currently available tasks.
* ```setConcurrency```: A function that is used to change concurrency at runtime.

### Following variables reveals current state of JobManager instance.
* ```state```: NOT_RUNNING | RUNNING.
* ```isLoadingTakingPlace```: onLoadMore function is taking place.


Demo
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 A pure javascript demo at http://harish2704.github.io/jobmanager-demo/test.html will give a more cleat idea. This demo uses the same JobManager class to do the animation.