distribution/notifications/bridge.go
Stephen J Day 26b7fe4a91 Use "Size" field to describe blobs over "Length"
After consideration, we've changed the main descriptor field name to for number
of bytes to "size" to match convention. While this may be a subjective
argument, commonly we refer to files by their "size" rather than their
"length". This will match other conventions, like `(FileInfo).Size()` and
methods on `io.SizeReaderAt`. Under more broad analysis, this argument doesn't
necessarily hold up. If anything, "size" is shorter than "length".

Signed-off-by: Stephen J Day <stephen.day@docker.com>
2015-07-17 17:07:11 -07:00

155 lines
4.2 KiB
Go

package notifications
import (
"net/http"
"time"
"github.com/docker/distribution"
"github.com/docker/distribution/context"
"github.com/docker/distribution/digest"
"github.com/docker/distribution/manifest"
"github.com/docker/distribution/uuid"
)
type bridge struct {
ub URLBuilder
actor ActorRecord
source SourceRecord
request RequestRecord
sink Sink
}
var _ Listener = &bridge{}
// URLBuilder defines a subset of url builder to be used by the event listener.
type URLBuilder interface {
BuildManifestURL(name, tag string) (string, error)
BuildBlobURL(name string, dgst digest.Digest) (string, error)
}
// NewBridge returns a notification listener that writes records to sink,
// using the actor and source. Any urls populated in the events created by
// this bridge will be created using the URLBuilder.
// TODO(stevvooe): Update this to simply take a context.Context object.
func NewBridge(ub URLBuilder, source SourceRecord, actor ActorRecord, request RequestRecord, sink Sink) Listener {
return &bridge{
ub: ub,
actor: actor,
source: source,
request: request,
sink: sink,
}
}
// NewRequestRecord builds a RequestRecord for use in NewBridge from an
// http.Request, associating it with a request id.
func NewRequestRecord(id string, r *http.Request) RequestRecord {
return RequestRecord{
ID: id,
Addr: context.RemoteAddr(r),
Host: r.Host,
Method: r.Method,
UserAgent: r.UserAgent(),
}
}
func (b *bridge) ManifestPushed(repo string, sm *manifest.SignedManifest) error {
return b.createManifestEventAndWrite(EventActionPush, repo, sm)
}
func (b *bridge) ManifestPulled(repo string, sm *manifest.SignedManifest) error {
return b.createManifestEventAndWrite(EventActionPull, repo, sm)
}
func (b *bridge) ManifestDeleted(repo string, sm *manifest.SignedManifest) error {
return b.createManifestEventAndWrite(EventActionDelete, repo, sm)
}
func (b *bridge) BlobPushed(repo string, desc distribution.Descriptor) error {
return b.createBlobEventAndWrite(EventActionPush, repo, desc)
}
func (b *bridge) BlobPulled(repo string, desc distribution.Descriptor) error {
return b.createBlobEventAndWrite(EventActionPull, repo, desc)
}
func (b *bridge) BlobDeleted(repo string, desc distribution.Descriptor) error {
return b.createBlobEventAndWrite(EventActionDelete, repo, desc)
}
func (b *bridge) createManifestEventAndWrite(action string, repo string, sm *manifest.SignedManifest) error {
manifestEvent, err := b.createManifestEvent(action, repo, sm)
if err != nil {
return err
}
return b.sink.Write(*manifestEvent)
}
func (b *bridge) createManifestEvent(action string, repo string, sm *manifest.SignedManifest) (*Event, error) {
event := b.createEvent(action)
event.Target.MediaType = manifest.ManifestMediaType
event.Target.Repository = repo
p, err := sm.Payload()
if err != nil {
return nil, err
}
event.Target.Length = int64(len(p))
event.Target.Size = int64(len(p))
event.Target.Digest, err = digest.FromBytes(p)
if err != nil {
return nil, err
}
event.Target.URL, err = b.ub.BuildManifestURL(sm.Name, event.Target.Digest.String())
if err != nil {
return nil, err
}
return event, nil
}
func (b *bridge) createBlobEventAndWrite(action string, repo string, desc distribution.Descriptor) error {
event, err := b.createBlobEvent(action, repo, desc)
if err != nil {
return err
}
return b.sink.Write(*event)
}
func (b *bridge) createBlobEvent(action string, repo string, desc distribution.Descriptor) (*Event, error) {
event := b.createEvent(action)
event.Target.Descriptor = desc
event.Target.Length = desc.Size
event.Target.Repository = repo
var err error
event.Target.URL, err = b.ub.BuildBlobURL(repo, desc.Digest)
if err != nil {
return nil, err
}
return event, nil
}
// createEvent creates an event with actor and source populated.
func (b *bridge) createEvent(action string) *Event {
event := createEvent(action)
event.Source = b.source
event.Actor = b.actor
event.Request = b.request
return event
}
// createEvent returns a new event, timestamped, with the specified action.
func createEvent(action string) *Event {
return &Event{
ID: uuid.Generate().String(),
Timestamp: time.Now(),
Action: action,
}
}