grpc-proxy fix + Go dep + Update/Lock Dependencies

.gitignore

@@ -162,3 +162,4 @@ ENV/
 .ropeproject
 
 node_modules
+vendor

.travis.yml

@@ -18,20 +18,11 @@ before_install:
   - true && `base64 --decode <<< ZXhwb3J0IEJST1dTRVJfU1RBQ0tfVVNFUk5BTUU9aW1wcm9iYWJsZWVuZ2JvdDEK`
   - true && `base64 --decode <<< ZXhwb3J0IEJST1dTRVJfU1RBQ0tfQUNDRVNTX0tFWT1xTGJxUjE2azhqdFducVh2RmlvZwo=`
 install:
+  - go get -u github.com/golang/dep/cmd/dep
+  - go get github.com/golang/protobuf/protoc-gen-go
+  - dep ensure
   - export PATH=/home/travis/gopath/src/github.com/improbable-eng/grpc-web/protobuf/bin:$PATH
   - rm -rf ~/.nvm && git clone https://github.com/creationix/nvm.git ~/.nvm && (cd ~/.nvm && git checkout `git describe --abbrev=0 --tags`) && source ~/.nvm/nvm.sh && nvm install 6
-  - go get github.com/sirupsen/logrus
-  - go get github.com/grpc-ecosystem/go-grpc-prometheus
-  - go get github.com/mwitkow/go-conntrack
-  - go get github.com/mwitkow/go-conntrack/connhelpers
-  - go get github.com/mwitkow/go-grpc-middleware
-  - go get github.com/mwitkow/go-grpc-middleware/logging/logrus
-  - go get github.com/mwitkow/grpc-proxy/proxy
-  - go get github.com/prometheus/client_golang/prometheus/promhttp
-  - go get github.com/spf13/pflag
-  - go get github.com/rs/cors
-  - go get github.com/golang/protobuf/protoc-gen-go
-  - go get github.com/stretchr/testify
   - npm install
 script:
   - npm run test

Gopkg.toml

@@ -0,0 +1,70 @@
+
+# Gopkg.toml example
+#
+# Refer to https://github.com/golang/dep/blob/master/docs/Gopkg.toml.md
+# for detailed Gopkg.toml documentation.
+#
+# required = ["github.com/user/thing/cmd/thing"]
+# ignored = ["github.com/user/project/pkgX", "bitbucket.org/user/project/pkgA/pkgY"]
+#
+# [[constraint]]
+#   name = "github.com/user/project"
+#   version = "1.0.0"
+#
+# [[constraint]]
+#   name = "github.com/user/project2"
+#   branch = "dev"
+#   source = "github.com/myfork/project2"
+#
+# [[override]]
+#  name = "github.com/x/y"
+#  version = "2.4.0"
+
+
+[[constraint]]
+  branch = "master"
+  name = "github.com/golang/protobuf"
+
+[[constraint]]
+  branch = "master"
+  name = "github.com/grpc-ecosystem/go-grpc-middleware"
+
+[[constraint]]
+  name = "github.com/grpc-ecosystem/go-grpc-prometheus"
+  version = "1.1.0"
+
+[[constraint]]
+  branch = "master"
+  name = "github.com/mwitkow/go-conntrack"
+
+[[constraint]]
+  branch = "master"
+  name = "github.com/mwitkow/grpc-proxy"
+
+[[constraint]]
+  name = "github.com/prometheus/client_golang"
+  version = "0.8.0"
+
+[[constraint]]
+  name = "github.com/rs/cors"
+  version = "1.2.0"
+
+[[constraint]]
+  name = "github.com/sirupsen/logrus"
+  version = "1.0.3"
+
+[[constraint]]
+  name = "github.com/spf13/pflag"
+  version = "1.0.0"
+
+[[constraint]]
+  name = "github.com/stretchr/testify"
+  version = "1.1.4"
+
+[[constraint]]
+  branch = "master"
+  name = "golang.org/x/net"
+
+[[constraint]]
+  name = "google.golang.org/grpc"
+  version = "1.8.0"

go/grpcwebproxy/main.go

@@ -11,18 +11,19 @@ import (
 
 	"crypto/tls"
 
-	"github.com/sirupsen/logrus"
-	"github.com/grpc-ecosystem/go-grpc-middleware"
 	"github.com/grpc-ecosystem/go-grpc-middleware/logging/logrus"
-	"github.com/grpc-ecosystem/go-grpc-prometheus"
 	"github.com/improbable-eng/grpc-web/go/grpcweb"
-	"github.com/mwitkow/go-conntrack"
 	"github.com/mwitkow/grpc-proxy/proxy"
 	"github.com/prometheus/client_golang/prometheus/promhttp"
+	"github.com/sirupsen/logrus"
 	"github.com/spf13/pflag"
 	"golang.org/x/net/context"
 	_ "golang.org/x/net/trace" // register in DefaultServerMux
 	"google.golang.org/grpc"
+	"google.golang.org/grpc/metadata"
+	"github.com/grpc-ecosystem/go-grpc-middleware"
+	"github.com/grpc-ecosystem/go-grpc-prometheus"
+	"github.com/mwitkow/go-conntrack"
 )
 
 var (
@@ -92,8 +93,11 @@ func buildGrpcProxyServer(logger *logrus.Entry) *grpc.Server {
 
 	// gRPC proxy logic.
 	backendConn := dialBackendOrFail()
-	director := func(ctx context.Context, fullMethodName string) (*grpc.ClientConn, error) {
-		return backendConn, nil
+	director := func(ctx context.Context, fullMethodName string) (context.Context, *grpc.ClientConn, error) {
+		md, _ := metadata.FromIncomingContext(ctx)
+		outCtx, _ := context.WithCancel(ctx)
+		outCtx = metadata.NewOutgoingContext(outCtx, md.Copy())
+		return outCtx, backendConn, nil
 	}
 	// Server with logging and monitoring enabled.
 	return grpc.NewServer(