Get bundle as a string with programmatically usage with 0.6.x

[topa]

We're using for alamid's client tests nof5.
nof5 is basically a server which is able to use different bundlers, e.g. webpack, to bundle and serve client tests. One advantage of nof5 is that there is no need to write any tmp-file for the tests. So you won't have any problems with permissions.
So nof5 expects from the bundlers to be able to return a bundle as a string.
This is how webpack is implemented as bundler for nof5: WebpackBundler.
I wanted to updated the dependecy to webpack to version 0.6.x, but webpack isn't return a string any more.

Is there any possibility to get the bundle as string?

[sokra]

yes. There is an option noWrite and you need to pass the option emitFile to get the source of a file.

Here is a working example: https://github.com/webpack/worker-loader/blob/master/index.js

It's a webpack loader which compiles to WebWorker.
It's called from the parent webpack and executes a embedded webpack. The embeddend webpack do not write out files, but the worker-loader grabs the emitted files and pass them to the parent webpack.

Good luck.

[sokra]

The API which returns the source in the callback was deprecated in webpack 0.5 and I removed it in 0.6. The reason for removing was that many loader would not work with the old API because they emit files. I. e. file-loader.

The webpack-dev-middleware also do webpack in memory: https://github.com/webpack/webpack-dev-middleware/blob/master/middleware.js#L15

[topa]

Thank you for your fast response. I'm not sure if I got it, but are the following steps correct?

• first: set noWrite to true
• second: define with emitFile a function that collects the source of each file, like function collectSources(filename, content) { /* do some collecting stuff */ }
• third: execute webpack(absolutePath, options, function(err, stats) { /* nothing really to do here */})
• fourth: on "bundle"-event webpack has finished and I can return in any way the collected sources

If I try it like described I get the following error:

Error: options.output is required

[sokra]

Set output to the name of the bundled file, i. e. bundle.js.

You don't need the "bundle" event just use the callback in third.

webpack(absoluteFile, {
  output: "bundle.js",
  noWrite: true,
  emitFile: function(name, stringOrBuffer) {
    files[name] = stringOrBuffer;
  }
}, function(err, stats) {
  if(err) return handleError(err);
  processFiles(files);
})

[topa]

Thank you again for your fast response and help. It works now. If you like to you can take a look my implementation here: WebpackBundler

[sokra]

peerigon/nof5#10
peerigon/nof5#11

[AndersDJohnson]

How to do this with webpack 1.x or later? emitFile and noWrite seem gone. Already changed absoluteFile arg to entry: absoluteFile in config options.

Only possible with memory file system, e.g. https://webpack.github.io/docs/node.js-api.html#compile-to-memory? Or custom read from filesystem after compile?