You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

76 lines
1.8 KiB
JavaScript

5 years ago
var async = require('./async.js')
, abort = require('./abort.js')
;
// API
module.exports = iterate;
/**
* Iterates over each job object
*
* @param {array|object} list - array or object (named list) to iterate over
* @param {function} iterator - iterator to run
* @param {object} state - current job status
* @param {function} callback - invoked when all elements processed
*/
function iterate(list, iterator, state, callback)
{
// store current index
var key = state['keyedList'] ? state['keyedList'][state.index] : state.index;
state.jobs[key] = runJob(iterator, key, list[key], function(error, output)
{
// don't repeat yourself
// skip secondary callbacks
if (!(key in state.jobs))
{
return;
}
// clean up jobs
delete state.jobs[key];
if (error)
{
// don't process rest of the results
// stop still active jobs
// and reset the list
abort(state);
}
else
{
state.results[key] = output;
}
// return salvaged results
callback(error, state.results);
});
}
/**
* Runs iterator over provided job element
*
* @param {function} iterator - iterator to invoke
* @param {string|number} key - key/index of the element in the list of jobs
* @param {mixed} item - job description
* @param {function} callback - invoked after iterator is done with the job
* @returns {function|mixed} - job abort function or something else
*/
function runJob(iterator, key, item, callback)
{
var aborter;
// allow shortcut if iterator expects only two arguments
if (iterator.length == 2)
{
aborter = iterator(item, async(callback));
}
// otherwise go with full three arguments
else
{
aborter = iterator(item, key, async(callback));
}
return aborter;
}