Use isHttp2 check to detect we are canceling an HTTP2 request (#433)

Author: mcollina

index.js

@@ -47,6 +47,8 @@ const fastifyReplyFrom = fp(function from (fastify, opts, next) {
     globalAgent: opts.globalAgent,
     destroyAgent: opts.destroyAgent
   })
+
+  const isHttp2 = !!opts.http2
   if (requestBuilt instanceof Error) {
     next(requestBuilt)
     return
@@ -209,7 +211,7 @@ const fastifyReplyFrom = fp(function from (fastify, opts, next) {
         onError(this, { error: new BadGatewayError() })
         this.request.log.warn(err, 'response has invalid status code')
       }
-      if (this.request.raw.aborted && res.stream) {
+      if (this.request.raw.aborted && isHttp2) {
         // the request could have been canceled before we got a response from the target
         // forward this to the upstream server and close the stream to prevent leaks
         res.stream.close(NGHTTP2_CANCEL)