moby/api/server/httputils/httputils.go
Sebastiaan van Stijn 0507c358d9
API: explicitely ignore unhandled errors
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
2019-09-18 12:57:13 +02:00

124 lines
3.7 KiB
Go

package httputils // import "github.com/docker/docker/api/server/httputils"
import (
"context"
"io"
"mime"
"net/http"
"strings"
"github.com/docker/docker/api/types"
"github.com/docker/docker/api/types/versions"
"github.com/docker/docker/errdefs"
"github.com/gorilla/mux"
"github.com/pkg/errors"
"github.com/sirupsen/logrus"
"google.golang.org/grpc/status"
)
// APIVersionKey is the client's requested API version.
type APIVersionKey struct{}
// 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
// HijackConnection interrupts the http response writer to get the
// underlying connection and operate with it.
func HijackConnection(w http.ResponseWriter) (io.ReadCloser, io.Writer, error) {
conn, _, err := w.(http.Hijacker).Hijack()
if err != nil {
return nil, nil, err
}
// Flush the options to make sure the client sets the raw mode
_, _ = conn.Write([]byte{})
return conn, conn, nil
}
// CloseStreams ensures that a list for http streams are properly closed.
func CloseStreams(streams ...interface{}) {
for _, stream := range streams {
if tcpc, ok := stream.(interface {
CloseWrite() error
}); ok {
_ = tcpc.CloseWrite()
} else if closer, ok := stream.(io.Closer); ok {
_ = closer.Close()
}
}
}
// CheckForJSON makes sure that the request's Content-Type is application/json.
func CheckForJSON(r *http.Request) error {
ct := r.Header.Get("Content-Type")
// No Content-Type header is ok as long as there's no Body
if ct == "" {
if r.Body == nil || r.ContentLength == 0 {
return nil
}
}
// Otherwise it better be json
if matchesContentType(ct, "application/json") {
return nil
}
return errdefs.InvalidParameter(errors.Errorf("Content-Type specified (%s) must be 'application/json'", ct))
}
// ParseForm ensures the request form is parsed even with invalid content types.
// If we don't do this, POST method without Content-type (even with empty body) will fail.
func ParseForm(r *http.Request) error {
if r == nil {
return nil
}
if err := r.ParseForm(); err != nil && !strings.HasPrefix(err.Error(), "mime:") {
return errdefs.InvalidParameter(err)
}
return nil
}
// VersionFromContext returns an API version from the context using APIVersionKey.
// It panics if the context value does not have version.Version type.
func VersionFromContext(ctx context.Context) string {
if ctx == nil {
return ""
}
if val := ctx.Value(APIVersionKey{}); val != nil {
return val.(string)
}
return ""
}
// MakeErrorHandler makes an HTTP handler that decodes a Docker error and
// returns it in the response.
func MakeErrorHandler(err error) http.HandlerFunc {
return func(w http.ResponseWriter, r *http.Request) {
statusCode := errdefs.GetHTTPErrorStatusCode(err)
vars := mux.Vars(r)
if apiVersionSupportsJSONErrors(vars["version"]) {
response := &types.ErrorResponse{
Message: err.Error(),
}
_ = WriteJSON(w, statusCode, response)
} else {
http.Error(w, status.Convert(err).Message(), statusCode)
}
}
}
func apiVersionSupportsJSONErrors(version string) bool {
const firstAPIVersionWithJSONErrors = "1.23"
return version == "" || versions.GreaterThan(version, firstAPIVersionWithJSONErrors)
}
// matchesContentType validates the content type against the expected one
func matchesContentType(contentType, expectedType string) bool {
mimetype, _, err := mime.ParseMediaType(contentType)
if err != nil {
logrus.Errorf("Error parsing media type: %s error: %v", contentType, err)
}
return err == nil && mimetype == expectedType
}