Allow update of "headers" dict w/ request kwargs

[Datamance]

Hi,

Is there an easy way to mock request headers - or do I need to monkey patch something in the library? Let me know - thanks!

[Datamance]

Specifically, it'd be nice to mock them at request time (as opposed to just in the config) - this would allow me to do things like faking an origin for testing purposes.

[Datamance]

K, apparently you can just pass in request headers as kwargs straight through to the requests lib, which you use here,

However, you don't update the request kwargs properly so I have to re-add request headers that should just be there already, like Content-Type and Accept:

response = nps_endpoint.post(
            object=nps_for_product,
            headers={
                'Origin': product['attributes']['url'],
                'Content-Type': 'application/vnd.api+json',
                'Accept': 'application/vnd.api+json'
            })

I can submit a PR for this later this week, maybe even tonight.

[jgoclawski]

Glad you found it! PRs ale welcome of course. It makes sense to extend default headers instead of overriding them. Make sure to include tests, so that the review goes quicker.