distribution/docs/layer.go
Brian Bland b11d549fd0 Adds support for content redirects for layer downloads
Includes a delegate implementation which redirects to the URL generated
by the storagedriver, and a cloudfront implementation.
Satisfies proposal #49
2015-01-08 17:01:28 -08:00

69 lines
1.6 KiB
Go

package registry
import (
"net/http"
"github.com/docker/distribution/api/v2"
"github.com/docker/distribution/digest"
"github.com/docker/distribution/storage"
"github.com/gorilla/handlers"
)
// layerDispatcher uses the request context to build a layerHandler.
func layerDispatcher(ctx *Context, r *http.Request) http.Handler {
dgst, err := digest.ParseDigest(ctx.vars["digest"])
if err != nil {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
ctx.Errors.Push(v2.ErrorCodeDigestInvalid, err)
})
}
layerHandler := &layerHandler{
Context: ctx,
Digest: dgst,
}
layerHandler.log = layerHandler.log.WithField("digest", dgst)
return handlers.MethodHandler{
"GET": http.HandlerFunc(layerHandler.GetLayer),
"HEAD": http.HandlerFunc(layerHandler.GetLayer),
}
}
// layerHandler serves http layer requests.
type layerHandler struct {
*Context
Digest digest.Digest
}
// GetLayer fetches the binary data from backend storage returns it in the
// response.
func (lh *layerHandler) GetLayer(w http.ResponseWriter, r *http.Request) {
layers := lh.services.Layers()
layer, err := layers.Fetch(lh.Name, lh.Digest)
if err != nil {
switch err := err.(type) {
case storage.ErrUnknownLayer:
w.WriteHeader(http.StatusNotFound)
lh.Errors.Push(v2.ErrorCodeBlobUnknown, err.FSLayer)
default:
lh.Errors.Push(v2.ErrorCodeUnknown, err)
}
return
}
defer layer.Close()
handler, err := lh.layerHandler.Resolve(layer)
if handler != nil {
handler.ServeHTTP(w, r)
return
}
http.ServeContent(w, r, layer.Digest().String(), layer.CreatedAt(), layer)
}