distribution/docs/storage/layerreader.go
David Lawrence 952f39edff Refactoring cloudfactory layer handler into a more generic storage
middleware concept.

This also breaks the dependency the storage package had on goamz
Signed-off-by: David Lawrence <david.lawrence@docker.com> (github: endophage)
2015-03-11 08:56:28 -07:00

49 lines
1.1 KiB
Go

package storage
import (
"net/http"
"time"
"github.com/docker/distribution"
"github.com/docker/distribution/digest"
)
// LayerRead implements Layer and provides facilities for reading and
// seeking.
type layerReader struct {
fileReader
digest digest.Digest
}
var _ distribution.Layer = &layerReader{}
func (lrs *layerReader) Path() string {
return lrs.path
}
func (lrs *layerReader) Digest() digest.Digest {
return lrs.digest
}
func (lrs *layerReader) Length() int64 {
return lrs.size
}
func (lrs *layerReader) CreatedAt() time.Time {
return lrs.modtime
}
// Close the layer. Should be called when the resource is no longer needed.
func (lrs *layerReader) Close() error {
return lrs.closeWithErr(distribution.ErrLayerClosed)
}
func (lrs *layerReader) ServeHTTP(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Docker-Content-Digest", lrs.digest.String())
if url, err := lrs.fileReader.driver.URLFor(lrs.Path(), map[string]interface{}{}); err == nil {
http.Redirect(w, r, url, http.StatusTemporaryRedirect)
}
http.ServeContent(w, r, lrs.Digest().String(), lrs.CreatedAt(), lrs)
}