github.com/hustcat/docker@v1.3.3-0.20160314103604-901c67a8eeab/api/server/middleware/user_agent.go (about)

     1  package middleware
     2  
     3  import (
     4  	"net/http"
     5  	"strings"
     6  
     7  	"github.com/Sirupsen/logrus"
     8  	"github.com/docker/docker/api/server/httputils"
     9  	"github.com/docker/docker/pkg/version"
    10  	"golang.org/x/net/context"
    11  )
    12  
    13  // NewUserAgentMiddleware creates a new UserAgent middleware.
    14  func NewUserAgentMiddleware(versionCheck string) Middleware {
    15  	serverVersion := version.Version(versionCheck)
    16  
    17  	return func(handler httputils.APIFunc) httputils.APIFunc {
    18  		return func(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
    19  			if strings.Contains(r.Header.Get("User-Agent"), "Docker-Client/") {
    20  				userAgent := strings.Split(r.Header.Get("User-Agent"), "/")
    21  
    22  				// v1.20 onwards includes the GOOS of the client after the version
    23  				// such as Docker/1.7.0 (linux)
    24  				if len(userAgent) == 2 && strings.Contains(userAgent[1], " ") {
    25  					userAgent[1] = strings.Split(userAgent[1], " ")[0]
    26  				}
    27  
    28  				if len(userAgent) == 2 && !serverVersion.Equal(version.Version(userAgent[1])) {
    29  					logrus.Debugf("Client and server don't have the same version (client: %s, server: %s)", userAgent[1], serverVersion)
    30  				}
    31  			}
    32  			return handler(ctx, w, r, vars)
    33  		}
    34  	}
    35  }