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POnode.js async parallel function returns a single result several times
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copied!<p>I'm trying to upload several files in parallel using node.js's async module. My code looks like: </p> <pre><code>// fileArr is an array of objects. each object contains the attributes of the file to be uploaded - filename, path, destination path, etc. // toUpload is an array to which i push all the functions i want to execute with async.parallel for (i=0; i<fileArr.length; i++) { var src = fileArr[i]['path'] var dest = fileArr[i]['dest'] var fn = function(cb) { self.upload(src, dest, headers, function(err, url) { cb(null, url) }) } toUpload.push(fn) } // for loop ends here async.parallel(toUpload, function(err, results) { console.log('results: ' + results) }) </code></pre> <p>My problem: for n = the number of functions in toUpload, the results array callback contains the result from the last parallel task in the array, n times. I can't figure this out. it seems like every function should return its own callback with (null, url) to the parallel function.</p> <p>also - when i try calling the self.upload function with the definitions of src and dest directly:</p> <pre><code>self.upload(fileArr[i]['path'], fileArr[i]['dest'], headers, function(err, url) { cb(null, url) }) </code></pre> <p>i get a error saying "cannot read property 'path' of undefined". so, fileArr[i] is undefined. why does this happen? i feel like there is some weirdness with assignments and scope going on...</p> <p>if it's not immediately obvious from the question (and the code), i'm pretty new to programming..</p>

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