Add support for API version 2019-03-14

[remi-stripe]

The changes in the library itself look minor. But this API version changes the behavior of Subscriptions entirely under the hood. If the charge fails, you still get a Subscription back instead of an exception and it's on you to check the Subscription status.

This is now fully ready to be reviewed. It also changes the apiversion internal-only constant to a public one.

r? @brandur-stripe
cc @stripe/api-libraries

Related to stripe/stripe-dotnet#1552

[brandur-stripe]

The changes in the library itself look minor. But this API version changes the behavior of Subscriptions entirely under the hood. If the charge fails, you still get a Subscription back instead of an exception and it's on you to check the Subscription status.

Oh, very good to know! Thanks.

LGTM.

[remi-stripe]

@brandur-stripe I ended up finding a bug in the library which I fixed in #814. After that one is merged, we can properly force the new stripe-mock flag to test the API version in the library is the correct one.

Because of this, apiVersion now has to be exported so I renamed it.

PTAL

[brandur-stripe]

Because of this, apiVersion now has to be exported so I renamed it.

IMO, this is okay. It may be useful to print informational logs or something in client applications anyway. As long as it stays as a const, it can't be abused (by people overwriting it to a new value, etc.).

[brandur-stripe]

Released as 58.0.0.