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If I have a node.js application that is filled with many require statements, how can I compile this into a single .js file? I'd have to manually resolve the require statements and ensure that the classes are loaded in the correct order. Is there some tool that does this?

Let me clarify.

The code that is being run on node.js is not node specific. The only thing I'm doing that doesn't have a direct browser equivalent is using require, which is why I'm asking. It is not using any of the node libraries.

ryeguy
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  • @Raynos: I don't know if you understand what I'm asking. When you're developing a complex application, you're going to split it into multiple files, right (one file per class, etc)? That works fine on the backend when running it on node and using `require`, but if I wanted to run the same js app in the browser the client shouldn't have to download dozens of js files, they should download one concatenated file. – ryeguy Apr 13 '11 at 21:43
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    @Raynos: Is your tone necessary? You're assuming so many things I never said. Check my edit. – ryeguy Apr 13 '11 at 21:51
  • @ryeguy. Sorry it's a bit over the top. But if you could get node to run as a chrome extension that would be great. – Raynos Apr 13 '11 at 21:57
  • I think for the most part your question becomes "how can I combine multiple js files into one", which I am assuming is a solved problem? Surely the jQuery team doesn't develop jQuery all in one file? Or do they? – Matt Greer Apr 13 '11 at 22:08
  • @MattGreer jQuery does not have the same kind of module loading system as node.js has. There is a large chain of dependencies to resolve for node.js – Raynos Apr 13 '11 at 22:14

4 Answers4

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You can use webpack with target: 'node', it will inline all required modules and export everything as a single, standalone, one file, nodejs module

https://webpack.js.org/configuration/target/#root

2021 edit: There are now other solutions you could investigate, examples.

Namely:

vvo
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Try below:

  1. npm i -g @vercel/ncc

  2. ncc build app.ts -o dist

see detail here https://stackoverflow.com/a/65317389/1979406

Haryono
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If you want to send common code to the browser I would personally recommend something like brequire or requireJS which can "compile" your nodeJS source into asynchronously loading code whilst maintaining the order.

For an actual compiler into a single file you might get away with one for requireJS but I would not trust it with large projects with high complexity and edge-cases.

It shouldn't be too hard to write a file like package.json that npm uses to state in which order the files should occur in your packaging. This way it's your responsibility to make sure everything is compacted in the correct order, you can then write a simplistic node application to reads your package.json file and uses file IO to create your compiled script.

Automatically generating the order in which files should be packaged requires building up a dependency tree and doing lots of file parsing. It should be possible but it will probably crash on circular dependencies. I don't know of any libraries out there to do this for you.

Raynos
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  • See my edit. I don't want to package code on the server. I want to use the same code on the client as I do on the server. It is not node specific aside from the require statements. I want to compile it to one file so the client only has to download one file. – ryeguy Apr 13 '11 at 21:52
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Do NOT use requireJS if you value your sanity. I've seen it used in a largish project and it was an absolute disaster ... maybe the worst technical choice made at that company. RequireJS is designed to run in-browser and to asynchronously and recursively load JS dependencies. That is a TERRIBLE idea. Browsers suck at loading lots and lots of little files over the network; every single doc on web performance will tell you this. So you'll very very quickly end up needing a solution to smash your JS files together ... at which point, what's the point of having an in-browser dependency resolution mechanism? And even though your production site will be smashed into a single JS file, with requireJS, your code must constantly assume that any dependency might or might not be loaded yet; in a complex project, this leads to thousands of async load barriers wrapping every interaction point between modules. At my last company, we had some places where the closure stack was 12+ levels deep. All that "if loaded yet" logic makes your code more complex and harder to work with. It also bloats the code increasing the number of bytes sent to the client. Plus, the client has to load the requireJS library itself, which burns another 14.4k. The size alone should tell you something about the level of feature creep in the requireJS project. For comparison, the entire underscore.js toolkit is only 4k.

What you want is a compile-time step for smashing JS together, not a heavyweight framework that will run in the browser....

You should check out https://github.com/substack/node-browserify

Browserify does exactly what you are asking for .... combines multiple NPM modules into a single JS file for distribution to the browser. The consolidated code is functionally identical to the original code, and the overhead is low (approx 4k + 140 bytes per additional file, including the "require('file')" line). If you are picky, you can cut out most of that 4k, which provides wrappers to emulate common node.js globals in the browser (eg "process.nextTick()").

Dave Dopson
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    We use requireJS and it has been very pleasant. We use Grunt to automagic build our js files into a single file of which is loaded (via magic(requireJS)) asynchronously. Sometimes bad experiences are due to drivers and not the car (btw, the code base is about 80K lines of javascript over about 100 files). – ThePrimeagen Sep 20 '12 at 15:34
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    There's probably some truth to "bad experiences ar due to drivers and not the car" .... I was using requireJS at a company that starts with a Z, makes games of questionable quality, and has a complete disregard for sustainable engineering practices... :). That being said, I still did feel like requireJS was overkill, and that it's fundamental perspective was a mismatch with how I'd want to think about bundling dependencies. – Dave Dopson Sep 20 '12 at 16:52
  • i understand now. Sorry for such a flaming comment, i should of taken it a bit easier. I do think that its good if you try using it with grunt/grunt-requirejs. At my company which starts with a W and does not do questionable engineering practices and does SEC Filings, uses requirejs. We hooked up grunt and now every time i make a single edit everything is automagically compiled and (with testacular) tested against unit tests (using jasmine). Its pretty neet. I didn't like require but now i do! (And there are definitely some headaches about it). – ThePrimeagen Sep 21 '12 at 17:19
  • Heh, my company now starts with a W also! And has vastly better engineering practices. :) We use Rails, and I've been rather pleasantly surprised with the Sprockets asset pipeline for stitching together JS files. – Dave Dopson Sep 22 '12 at 23:08
  • Requirejs is not all that bad when used right. Having multiple files can be very usefull when developing. And for production you should always compile your js in one file of course. – Elmer Feb 10 '13 at 16:24
  • @Elmer - For development, why not just include ALL your scripts directly from the document? ie, you get the same code behavior as having one monolithic JS file, but you have things broken into multiple non-minified files. I don't need RequireJS to get the dev benefit you are talking about, and my solution has 0 impact on the production artifacts. – Dave Dopson Feb 11 '13 at 20:14
  • My company starts with A! Oh this is not Reddit. – a20 Jul 02 '13 at 09:28