Push/pull errors improvement and cleanup

Several improvements to error handling:

- Introduce ImageConfigPullError type, wrapping errors related to
  downloading the image configuration blob in schema2. This allows for a
  more descriptive error message to be seen by the end user.

- Change some logrus.Debugf calls that display errors to logrus.Errorf.
  Add log lines in the push/pull fallback cases to make sure the errors
  leading to the fallback are shown.

- Move error-related types and functions which are only used by the
  distribution package out of the registry package.

Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
This commit is contained in:
Aaron Lehmann 2016-02-11 14:08:49 -08:00
parent 377f556464
commit 4bb475cd3c

View file

@ -13,13 +13,9 @@ import (
"path/filepath"
"runtime"
"strings"
"syscall"
"time"
"github.com/Sirupsen/logrus"
"github.com/docker/distribution/registry/api/errcode"
"github.com/docker/distribution/registry/api/v2"
"github.com/docker/distribution/registry/client"
"github.com/docker/distribution/registry/client/transport"
"github.com/docker/go-connections/tlsconfig"
)
@ -169,51 +165,6 @@ func addRequiredHeadersToRedirectedRequests(req *http.Request, via []*http.Reque
return nil
}
// ShouldV2Fallback returns true if this error is a reason to fall back to v1.
func ShouldV2Fallback(err errcode.Error) bool {
switch err.Code {
case errcode.ErrorCodeUnauthorized, v2.ErrorCodeManifestUnknown, v2.ErrorCodeNameUnknown:
return true
}
return false
}
// ErrNoSupport is an error type used for errors indicating that an operation
// is not supported. It encapsulates a more specific error.
type ErrNoSupport struct{ Err error }
func (e ErrNoSupport) Error() string {
if e.Err == nil {
return "not supported"
}
return e.Err.Error()
}
// ContinueOnError returns true if we should fallback to the next endpoint
// as a result of this error.
func ContinueOnError(err error) bool {
switch v := err.(type) {
case errcode.Errors:
if len(v) == 0 {
return true
}
return ContinueOnError(v[0])
case ErrNoSupport:
return ContinueOnError(v.Err)
case errcode.Error:
return ShouldV2Fallback(v)
case *client.UnexpectedHTTPResponseError:
return true
case error:
return !strings.Contains(err.Error(), strings.ToLower(syscall.ENOSPC.Error()))
}
// let's be nice and fallback if the error is a completely
// unexpected one.
// If new errors have to be handled in some way, please
// add them to the switch above.
return true
}
// NewTransport returns a new HTTP transport. If tlsConfig is nil, it uses the
// default TLS configuration.
func NewTransport(tlsConfig *tls.Config) *http.Transport {