distribution/docs/proxy/proxyregistry.go
Richard Scothern d1cb12fa3d Add pull through cache functionality to the Registry which can be configured
with a new `proxy` section in the configuration file.

Create a new registry type which delegates storage to a proxyBlobStore
and proxyManifestStore.  These stores will pull through data if not present
locally.  proxyBlobStore takes care not to write duplicate data to disk.

Add a scheduler to cleanup expired content. The scheduler runs as a background
goroutine.  When a blob or manifest is pulled through from the remote registry,
an entry is added to the scheduler with a TTL.  When the TTL expires the
scheduler calls a pre-specified function to remove the fetched resource.

Add token authentication to the registry middleware.  Get a token at startup
and preload the credential store with the username and password supplied in the
config file.

Allow resumable digest functionality to be disabled at runtime and disable
it when the registry is a pull through cache.

Signed-off-by: Richard Scothern <richard.scothern@gmail.com>
2015-08-04 16:09:55 -07:00

139 lines
4 KiB
Go

package proxy
import (
"net/http"
"net/url"
"github.com/docker/distribution"
"github.com/docker/distribution/configuration"
"github.com/docker/distribution/context"
"github.com/docker/distribution/registry/client"
"github.com/docker/distribution/registry/client/auth"
"github.com/docker/distribution/registry/client/transport"
"github.com/docker/distribution/registry/proxy/scheduler"
"github.com/docker/distribution/registry/storage"
"github.com/docker/distribution/registry/storage/driver"
)
// proxyingRegistry fetches content from a remote registry and caches it locally
type proxyingRegistry struct {
embedded distribution.Namespace // provides local registry functionality
scheduler *scheduler.TTLExpirationScheduler
remoteURL string
credentialStore auth.CredentialStore
challengeManager auth.ChallengeManager
}
// NewRegistryPullThroughCache creates a registry acting as a pull through cache
func NewRegistryPullThroughCache(ctx context.Context, registry distribution.Namespace, driver driver.StorageDriver, config configuration.Proxy) (distribution.Namespace, error) {
_, err := url.Parse(config.RemoteURL)
if err != nil {
return nil, err
}
v := storage.NewVacuum(ctx, driver)
s := scheduler.New(ctx, driver, "/scheduler-state.json")
s.OnBlobExpire(func(digest string) error {
return v.RemoveBlob(digest)
})
s.OnManifestExpire(func(repoName string) error {
return v.RemoveRepository(repoName)
})
err = s.Start()
if err != nil {
return nil, err
}
challengeManager := auth.NewSimpleChallengeManager()
cs, err := ConfigureAuth(config.RemoteURL, config.Username, config.Password, challengeManager)
if err != nil {
return nil, err
}
return &proxyingRegistry{
embedded: registry,
scheduler: s,
challengeManager: challengeManager,
credentialStore: cs,
remoteURL: config.RemoteURL,
}, nil
}
func (pr *proxyingRegistry) Scope() distribution.Scope {
return distribution.GlobalScope
}
func (pr *proxyingRegistry) Repositories(ctx context.Context, repos []string, last string) (n int, err error) {
return pr.embedded.Repositories(ctx, repos, last)
}
func (pr *proxyingRegistry) Repository(ctx context.Context, name string) (distribution.Repository, error) {
tr := transport.NewTransport(http.DefaultTransport,
auth.NewAuthorizer(pr.challengeManager, auth.NewTokenHandler(http.DefaultTransport, pr.credentialStore, name, "pull")))
localRepo, err := pr.embedded.Repository(ctx, name)
if err != nil {
return nil, err
}
localManifests, err := localRepo.Manifests(ctx, storage.SkipLayerVerification)
if err != nil {
return nil, err
}
remoteRepo, err := client.NewRepository(ctx, name, pr.remoteURL, tr)
if err != nil {
return nil, err
}
remoteManifests, err := remoteRepo.Manifests(ctx)
if err != nil {
return nil, err
}
return &proxiedRepository{
blobStore: proxyBlobStore{
localStore: localRepo.Blobs(ctx),
remoteStore: remoteRepo.Blobs(ctx),
scheduler: pr.scheduler,
},
manifests: proxyManifestStore{
repositoryName: name,
localManifests: localManifests, // Options?
remoteManifests: remoteManifests,
ctx: ctx,
scheduler: pr.scheduler,
},
name: name,
signatures: localRepo.Signatures(),
}, nil
}
// proxiedRepository uses proxying blob and manifest services to serve content
// locally, or pulling it through from a remote and caching it locally if it doesn't
// already exist
type proxiedRepository struct {
blobStore distribution.BlobStore
manifests distribution.ManifestService
name string
signatures distribution.SignatureService
}
func (pr *proxiedRepository) Manifests(ctx context.Context, options ...distribution.ManifestServiceOption) (distribution.ManifestService, error) {
// options
return pr.manifests, nil
}
func (pr *proxiedRepository) Blobs(ctx context.Context) distribution.BlobStore {
return pr.blobStore
}
func (pr *proxiedRepository) Name() string {
return pr.name
}
func (pr *proxiedRepository) Signatures() distribution.SignatureService {
return pr.signatures
}