feat(web-server): allow injection of custom middleware.

[shanear]

Took a crack at a simple way of adding custom middleware.

Closes #1612

[maksimr]

@shanear Thanks!

Knowledge about connect confuse me.
What do you think about create middleware as launcher or framework?

var DartMiddlewareFactory = function(config) {
return function(request, response, next) {
};
};

module.exports = {
  'middleware:Dart': ['type', DartMiddlewareFactory]
};

example karma.config.js

...
middleware: ["Dart"]
...

P.S. I use name middleware as example.

[shanear]

Interesting

It seems from the docs that launchers and frameworks are plugins, and all plugins are npm modules.
http://karma-runner.github.io/0.13/dev/plugins.html

Is that correct? It would be nice to be able to add project specific middleware without having to create a separate npm module for it.

Again this is helpful for working with less modern, enterprise-style api's.

[maksimr]

It would be nice to be able to add project specific middleware without having to create a separate npm module for it.

@shanear you can inline plugin:

...
plugins: ['karma-*', {'middleware:InlineMiddleware': inlineMiddlewareFactory}]
middliware: ['inlineMiddleware']
...

[shanear]

@maksimr great, i'll give that a shot.

[shanear]

@maksimr how does this look?

[maksimr]

@shanear Thanks! Looks good for me 👍

@zzo, @dignifiedquire what do you think about this feature?

[dignifiedquire]

I think this is a nice addition, but please add some documentation with example and squash your commits into one.

[shanear]

@dignifiedquire cool! These docs look ok?

If so, i'll squash everything up.

[dignifiedquire]

It might be good to mention that this is express/connect middleware, and have a link to their docs on how to write one.

[dignifiedquire]

Also it would be good to note that the middleware is used in the order they are included, as the order can matter if I remember correctly.

[shanear]

@dignifiedquire i agree with your notes. Updated.

Let me know what you think.

[zzo]

this looks very interesting - middleware authors need to ensure they call 'next' if they don't want to handle a request - def. an advanced feature. What are all of the parameters the factory function gets - more than just 'config'? The karma-dart factory function gets:

function (emitter, /* config.files */ files, /* config.basePath */ basePath,v/* config.karmaDartImports */ customImports, /* config.hostname */ hostname, /* config.port */ port, logger, customFileHandlers, /* config.dart2js */ dart2js) 

[shanear]

@zzo Yeah, it's def advanced, but opens up a lot of flexibility in how Karma can be used (IE: we're using it to test our app's integration with a not-very-modern enterprise API). Plus many people working with node seem to be familiar with how connect/express work.

The parameters are provided from the DI system.

[dignifiedquire]

@shanear the ordering note is still missing, other than that I think it looks good.

@zzo yes if you provide a custom plugin you can specify the parameters you want using di, which should be explained in the plugins docs.

[zzo]

got it thanks - yes I think this is a great feature and ideally the karma-dart (and maybe other plugins?) should be transitioned to to use this ideally :)

[shanear]

@dignifiedquire I added a sentence about the ordering.

shanear@8984164#diff-b671a3609847ca11870b94dac48fd028R288
"Middleware will be used in the order listed."

[dignifiedquire]

@zzo yes it might make a lot of sense to use this in karma-dart from what I remember.
@shanear sorry I can't read, go ahead and squash so we can ship this :)

[dignifiedquire]

Thanks a lot

[shanear]

awesome 🤘

thanks for all of y'alls help!

[dignifiedquire]

Published as 0.13.11

[zzo]

mary poppins? I just looked at it the other day and it's up and running from what I could tell

[dignifiedquire]

@zzo no all good old fashioned hand work

[dignifiedquire]

@zzo but all automated, just need to run grunt release and I'm done :)