GET option for ApolloSchemaDownloader

[mikepitre]

Feature request

It would be great if we had an option to use a GET http method for schema downloading/introspection as part of the ApolloCodegenLib.

Motivation

A 3rd party CMS we're using only supports GET requests against their GraphQL API. They expect a GET request and the IntrospectionQuery passed as a query param.

[designatednerd]

Out of sheer curiosity, what CMS is it?

[mikepitre]

haha np, it's Prismic

[AnthonyMDev]

@calvincestari Are you going to be able to support this with the changes you are making for the new codegen schema downloader currently?

[calvincestari]

Yes I believe so. If there are a few minor conflicts I'm expecting they'll be easy enough to fix up. I'll look at getting this into the next release.

@mikepitre have you done any proof-of-concept work trying to get this working?

[mikepitre]

@calvincestari I have it working, but I just have a quick and dirty implementation for now. I essentially extended ApolloSchemaDownloader and copied the downloadViaIntrospection function from the package into a new downloadViaIntrospectionGET function that just sets the httpMethod of the url request to GET and passes the introspection query as a param

[calvincestari]

Do you want to have a go at cleaning it up and submitting a PR? I believe it's just the request, as you mentioned, that needs to change. Working it nicely into the existing schema downloader API without simply adding another method is the trickier bit.

[mikepitre]

@calvincestari I have a rough PR I can submit, but unfortunately I don't have much time to commit to this at the moment. I can submit it as a draft if you'd like but I'm afraid I can't spend much more time on this for now.

#2010