@@ -14,9 +14,6 @@ import (

 // APIVersionKey is the client's requested API version.

 const APIVersionKey = "api-version"

-// UAStringKey is used as key type for user-agent string in net/context struct

-const UAStringKey = "upstream-user-agent"

-

 // APIFunc is an adapter to allow the use of ordinary functions as Docker API endpoints.

 // Any function that has the appropriate signature can be registered as an API endpoint (e.g. getVersion).

 type APIFunc func(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error

@@ -12,6 +12,7 @@ import (

 	"github.com/docker/docker/api/server/httputils"

 	"github.com/docker/docker/api/server/middleware"

 	"github.com/docker/docker/api/server/router"

+	"github.com/docker/docker/dockerversion"

 	"github.com/gorilla/mux"

 	"golang.org/x/net/context"

 )

@@ -128,7 +129,7 @@ func (s *Server) makeHTTPHandler(handler httputils.APIFunc) http.HandlerFunc {

 		// apply to all requests. Data that is specific to the

 		// immediate function being called should still be passed

 		// as 'args' on the function call.

-		ctx := context.WithValue(context.Background(), httputils.UAStringKey, r.Header.Get("User-Agent"))

+		ctx := context.WithValue(context.Background(), dockerversion.UAStringKey, r.Header.Get("User-Agent"))

 		handlerFunc := s.handlerWithGlobalMiddlewares(handler)

 		vars := mux.Vars(r)

@@ -4,12 +4,14 @@ import (

 	"fmt"

 	"runtime"

-	"github.com/docker/docker/api/server/httputils"

 	"github.com/docker/docker/pkg/parsers/kernel"

 	"github.com/docker/docker/pkg/useragent"

 	"golang.org/x/net/context"

 )

+// UAStringKey is used as key type for user-agent string in net/context struct

+const UAStringKey = "upstream-user-agent"

+

 // DockerUserAgent is the User-Agent the Docker client uses to identify itself.

 // In accordance with RFC 7231 (5.5.3) is of the form:

 //    [docker client's UA] UpstreamClient([upstream client's UA])

@@ -37,9 +39,9 @@ func DockerUserAgent(ctx context.Context) string {

 func getUserAgentFromContext(ctx context.Context) string {

 	var upstreamUA string

 	if ctx != nil {

-		var ki interface{} = ctx.Value(httputils.UAStringKey)

+		var ki interface{} = ctx.Value(UAStringKey)

 		if ki != nil {

-			upstreamUA = ctx.Value(httputils.UAStringKey).(string)

+			upstreamUA = ctx.Value(UAStringKey).(string)

 		}

 	}

 	return upstreamUA