Pass req_opts from constructor args to request in oauth2client

[abrgr]

This permits client code to pass options (e.g. proxy) directly to request (the transport library).

[ryanseys]

Could you write some docs on how I would use this?

[ryanseys]

Also, perhaps some simple tests to ensure the parameters are being passed correctly, and makes documenting much easier.

[abrgr]

I'll do my best to add the tests later today.

My usage looks like this:

var oauthOpts = {
    req_opts: {
        proxy: 'http:/myproxy:80'
    }
};

var oauth2Client = new OAuth2(
    cfg.google.clientId,
    cfg.google.clientSecret,
    cfg.google.clientUrl,
    oauthOpts
);

//...

Do you want me to add this to any of the markdown docs or just leave it here and in the tests?

[ryanseys]

Oh hmm. Yeah that's a little messy. Can we instead just add support for a proxy value in the oauthOpts object, rather than munging all the opts together?

[abrgr]

I liked the idea of being able to set arbitrary options on request because there are a few that I want set on all external API calls. In my case, I'm setting a proxy and timeout. The idea of munging all the opts seemed more in-line with https://github.com/google/google-api-nodejs-client/blob/master/lib/apirequest.js#L179, which allows arbitrary access to the request options.

That said, if you'd rather cherry-pick properties, I'm happy to make that change. Mind if I add proxy and timeout?

[ryanseys]

Yeah, arbitrary request options are available on the API request level but I didn't think about at the transporter level itself. :( In either case req_opts should probably be better named and use camel case to fit with our conventions. Perhaps requestOpts is a more explicit name to consider.

[abrgr]

You got it. I'll update it to requestOpts and add some tests.

[JustinBeckwith]

Greetings! And thanks for the contribution. Sadly - this PR has gotten really stale :( We're taking steps to respond to these in a more timely fashion to prevent this from happening in the future. Apologies!