Is there a way to create and run a dynamic script from karma.conf.js - karma-runner

Question

I'm using karma to run tests on an angularjs application.
There are a couple JavaScript functions that I would like to run at start-up, but they need to be dynamically created based on some system data. When running the app, this is handled with node.
Is there any way to create a script as a var and pass it to the files: [] rather than just using a pattern to load an existing file?
I can make this work by creating the file, saving it to disk then loading it normally, but that's messy.

Answer 1

You can create your own karma preprocessor script.
For a starting point use the following as example:
var fs = require('fs'),
path = require('path');
var createCustomPreprocessor = function (config, helper, logger) {
var log = logger.create('custom'),
// get here the configuration set in the karma.conf.js file
customConfig = config.customConfig || {};
// read more config here in case needed
...
// a preprocessor has to return a function that when completed will call
// the done callback with the preprocessed content
return function (content, file, done) {
log.debug('custom: processing "%s"\n', file.originalPath);
// your crazy code here
fs.writeFile(path.join(outputDirectory, name), ... , function (err) {
if (err) {
log.error(err);
}
done(content);
});
}
};
createCustomPreprocessor.$inject = ['config', 'helper', 'logger'];
module.exports = {
'preprocessor:custom': ['factory', createCustomPreprocessor]
};
Add a package.json with the dependencies and serve it as a module. ;)
For more examples have a look to more modules here: https://www.npmjs.org/search?q=karma%20preprocessor