Updating to the KEDA 2.0 external scaler gRPC interface

The notable change here is that there is an added StreamIsActive
RPC call. The New and Close RPCs are removed.

Fixes kedacore#3

Signed-off-by: Aaron Schlesinger <aaron@ecomaz.net>

Makefile

@@ -5,7 +5,12 @@ OPERATOR_DOCKER_IMG?=arschles/keda-http-operator:${GIT_TAG}
 
 .PHONY: gen-scaler
 gen-scaler:
-	protoc scaler/scaler.proto --go_out=plugins=grpc:externalscaler
+	protoc \
+		--go_out=scaler/gen/ \
+		--go_opt=paths=source_relative \
+		--go-grpc_out=scaler/gen/ \
+		--go-grpc_opt=paths=source_relative \
+		scaler/scaler.proto
 
 .PHONY: build-scaler
 build-scaler:

go.mod

@@ -10,6 +10,7 @@ require (
 	github.com/onsi/gomega v1.8.1
 	github.com/pkg/errors v0.8.1
 	google.golang.org/grpc v1.33.2
+	google.golang.org/grpc/cmd/protoc-gen-go-grpc v1.0.1 // indirect
 	google.golang.org/protobuf v1.25.0
 	k8s.io/api v0.17.2
 	k8s.io/apimachinery v0.17.2

go.sum

@@ -447,6 +447,9 @@ google.golang.org/grpc v1.25.1/go.mod h1:c3i+UQWmh7LiEpx4sFZnkU36qjEYZ0imhYfXVyQ
 google.golang.org/grpc v1.27.0/go.mod h1:qbnxyOmOxrQa7FizSgH+ReBfzJrCY1pSN7KXBS8abTk=
 google.golang.org/grpc v1.33.2 h1:EQyQC3sa8M+p6Ulc8yy9SWSS2GVwyRc83gAbG8lrl4o=
 google.golang.org/grpc v1.33.2/go.mod h1:JMHMWHQWaTccqQQlmk3MJZS+GWXOdAesneDmEnv2fbc=
+google.golang.org/grpc v1.35.0 h1:TwIQcH3es+MojMVojxxfQ3l3OF2KzlRxML2xZq0kRo8=
+google.golang.org/grpc/cmd/protoc-gen-go-grpc v1.0.1 h1:M8spwkmx0pHrPq+uMdl22w5CvJ/Y+oAJTIs9oGoCpOE=
+google.golang.org/grpc/cmd/protoc-gen-go-grpc v1.0.1/go.mod h1:6Kw0yEErY5E/yWrBtf03jp27GLLJujG4z/JK95pnjjw=
 google.golang.org/protobuf v0.0.0-20200109180630-ec00e32a8dfd/go.mod h1:DFci5gLYBciE7Vtevhsrf46CRTquxDuWsQurQQe4oz8=
 google.golang.org/protobuf v0.0.0-20200221191635-4d8936d0db64/go.mod h1:kwYJMbMJ01Woi6D6+Kah6886xMZcty6N08ah7+eCXa0=
 google.golang.org/protobuf v0.0.0-20200228230310-ab0ca4ff8a60/go.mod h1:cfTl7dwQJ+fmap5saPgwCLgHXTUD7jkjRqWcaiX5VyM=