remove subscriptions from allowed POST operations

[n1ru4l]

When executing a subscription operation a client expects multiple results which can best be expressed as a stream, while the incremental delivery RFC could be misused for describing how a stream of subscription events can be delivered to clients, it is clearly not the correct fit, as multipart requests are intended to be short-lived, while subscriptions could stay active for longer periods of time. Until alternative directions such as SSE events (as supported via graphql-helix and graphql-sse) are explored it might make sense to completely remove subscriptions from the list of allowed operations that can be executed via POST.

[benjie]

Agree. Further many servers when you POST a subscribe operation will execute it rather than subscribe, and that rarely makes sense to do.