github.com/sijibomii/docker@v0.0.0-20231230191044-5cf6ca554647/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  // UserAgentMiddleware is a middleware that
    14  // validates the client user-agent.
    15  type UserAgentMiddleware struct {
    16  	serverVersion version.Version
    17  }
    18  
    19  // NewUserAgentMiddleware creates a new UserAgentMiddleware
    20  // with the server version.
    21  func NewUserAgentMiddleware(s version.Version) UserAgentMiddleware {
    22  	return UserAgentMiddleware{
    23  		serverVersion: s,
    24  	}
    25  }
    26  
    27  // WrapHandler returns a new handler function wrapping the previous one in the request chain.
    28  func (u UserAgentMiddleware) WrapHandler(handler func(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error) func(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
    29  	return func(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error {
    30  		ctx = context.WithValue(ctx, httputils.UAStringKey, r.Header.Get("User-Agent"))
    31  
    32  		if strings.Contains(r.Header.Get("User-Agent"), "Docker-Client/") {
    33  			userAgent := strings.Split(r.Header.Get("User-Agent"), "/")
    34  
    35  			// v1.20 onwards includes the GOOS of the client after the version
    36  			// such as Docker/1.7.0 (linux)
    37  			if len(userAgent) == 2 && strings.Contains(userAgent[1], " ") {
    38  				userAgent[1] = strings.Split(userAgent[1], " ")[0]
    39  			}
    40  
    41  			if len(userAgent) == 2 && !u.serverVersion.Equal(version.Version(userAgent[1])) {
    42  				logrus.Debugf("Client and server don't have the same version (client: %s, server: %s)", userAgent[1], u.serverVersion)
    43  			}
    44  		}
    45  		return handler(ctx, w, r, vars)
    46  	}
    47  }