@@ -11,8 +11,10 @@ import (

 	"golang.org/x/net/context"

 )

+type contextKey string

+

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

-const APIVersionKey = "api-version"

+const APIVersionKey contextKey = "api-version"

 // 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).

@@ -5,6 +5,7 @@ import (

 	"net/http"

 	"runtime"

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

 	"github.com/docker/docker/api/types/versions"

 	"golang.org/x/net/context"

 )

@@ -57,8 +58,7 @@ func (v VersionMiddleware) WrapHandler(handler func(ctx context.Context, w http.

 		if versions.GreaterThan(apiVersion, v.defaultVersion) {

 			return versionUnsupportedError{version: apiVersion, maxVersion: v.defaultVersion}

 		}

-		// nolint: golint

-		ctx = context.WithValue(ctx, "api-version", apiVersion)

+		ctx = context.WithValue(ctx, httputils.APIVersionKey, apiVersion)

 		return handler(ctx, w, r, vars)

 	}