distribution: Add Tags

Add a function to return tags for the given repository reference. This
is needed to implement the `pull -a` (pull all tags) for containerd
which doesn't directly use distribution, but we need to somehow make an
API call to the registry to obtain the available tags.

Signed-off-by: Paweł Gronowski <pawel.gronowski@docker.com>
This commit is contained in:
Paweł Gronowski 2023-09-20 11:47:39 +02:00
parent 6040283f23
commit 095d2a29a3
No known key found for this signature in database
GPG key ID: B85EFCFE26DEF92A
2 changed files with 102 additions and 74 deletions

View file

@ -9,6 +9,7 @@ import (
"github.com/docker/docker/api"
"github.com/docker/docker/api/types/events"
refstore "github.com/docker/docker/reference"
"github.com/docker/docker/registry"
"github.com/opencontainers/go-digest"
"github.com/pkg/errors"
)
@ -16,73 +17,33 @@ import (
// Pull initiates a pull operation. image is the repository name to pull, and
// tag may be either empty, or indicate a specific tag to pull.
func Pull(ctx context.Context, ref reference.Named, config *ImagePullConfig, local ContentStore) error {
// Resolve the Repository name from fqn to RepositoryInfo
repoInfo, err := config.RegistryService.ResolveRepository(ref)
if err != nil {
return err
}
// makes sure name is not `scratch`
if err := validateRepoName(repoInfo.Name); err != nil {
return err
}
endpoints, err := config.RegistryService.LookupPullEndpoints(reference.Domain(repoInfo.Name))
if err != nil {
return err
}
var (
lastErr error
// confirmedTLSRegistries is a map indicating which registries
// are known to be using TLS. There should never be a plaintext
// retry for any of these.
confirmedTLSRegistries = make(map[string]struct{})
)
for _, endpoint := range endpoints {
if endpoint.URL.Scheme != "https" {
if _, confirmedTLS := confirmedTLSRegistries[endpoint.URL.Host]; confirmedTLS {
log.G(ctx).Debugf("Skipping non-TLS endpoint %s for host/port that appears to use TLS", endpoint.URL)
continue
}
}
repoInfo, err := pullEndpoints(ctx, config.RegistryService, ref, func(ctx context.Context, repoInfo registry.RepositoryInfo, endpoint registry.APIEndpoint) error {
log.G(ctx).Debugf("Trying to pull %s from %s", reference.FamiliarName(repoInfo.Name), endpoint.URL)
puller := newPuller(endpoint, &repoInfo, config, local)
return puller.pull(ctx, ref)
})
if err := newPuller(endpoint, repoInfo, config, local).pull(ctx, ref); err != nil {
// Was this pull cancelled? If so, don't try to fall
// back.
fallback := false
select {
case <-ctx.Done():
default:
if fallbackErr, ok := err.(fallbackError); ok {
fallback = true
if fallbackErr.transportOK && endpoint.URL.Scheme == "https" {
confirmedTLSRegistries[endpoint.URL.Host] = struct{}{}
}
err = fallbackErr.err
}
}
if fallback {
lastErr = err
log.G(ctx).Infof("Attempting next endpoint for pull after error: %v", err)
continue
}
log.G(ctx).Errorf("Not continuing with pull after error: %v", err)
return translatePullError(err, ref)
if err == nil {
config.ImageEventLogger(reference.FamiliarString(ref), reference.FamiliarName(repoInfo.Name), events.ActionPull)
}
return err
}
// Tags returns available tags for the given image in the remote repository.
func Tags(ctx context.Context, ref reference.Named, config *Config) ([]string, error) {
var tags []string
_, err := pullEndpoints(ctx, config.RegistryService, ref, func(ctx context.Context, repoInfo registry.RepositoryInfo, endpoint registry.APIEndpoint) error {
repo, err := newRepository(ctx, &repoInfo, endpoint, config.MetaHeaders, config.AuthConfig, "pull")
if err != nil {
return err
}
config.ImageEventLogger(reference.FamiliarString(ref), reference.FamiliarName(repoInfo.Name), events.ActionPull)
return nil
}
tags, err = repo.Tags(ctx).All(ctx)
return err
})
if lastErr == nil {
lastErr = fmt.Errorf("no endpoints found for %s", reference.FamiliarString(ref))
}
return translatePullError(lastErr, ref)
return tags, err
}
// validateRepoName validates the name of a repository.
@ -111,3 +72,81 @@ func addDigestReference(store refstore.Store, ref reference.Named, dgst digest.D
return store.AddDigest(dgstRef, id, true)
}
func pullEndpoints(ctx context.Context, registryService RegistryResolver, ref reference.Named,
f func(context.Context, registry.RepositoryInfo, registry.APIEndpoint) error,
) (*registry.RepositoryInfo, error) {
// Resolve the Repository name from fqn to RepositoryInfo
repoInfo, err := registryService.ResolveRepository(ref)
if err != nil {
return nil, err
}
// makes sure name is not `scratch`
if err := validateRepoName(repoInfo.Name); err != nil {
return repoInfo, err
}
endpoints, err := registryService.LookupPullEndpoints(reference.Domain(repoInfo.Name))
if err != nil {
return repoInfo, err
}
var (
lastErr error
// confirmedTLSRegistries is a map indicating which registries
// are known to be using TLS. There should never be a plaintext
// retry for any of these.
confirmedTLSRegistries = make(map[string]struct{})
)
for _, endpoint := range endpoints {
if endpoint.URL.Scheme != "https" {
if _, confirmedTLS := confirmedTLSRegistries[endpoint.URL.Host]; confirmedTLS {
log.G(ctx).Debugf("Skipping non-TLS endpoint %s for host/port that appears to use TLS", endpoint.URL)
continue
}
}
log.G(ctx).Debugf("Trying to pull %s from %s", reference.FamiliarName(repoInfo.Name), endpoint.URL)
if err := f(ctx, *repoInfo, endpoint); err != nil {
if _, ok := err.(fallbackError); !ok && continueOnError(err, endpoint.Mirror) {
err = fallbackError{
err: err,
transportOK: true,
}
}
// Was this pull cancelled? If so, don't try to fall
// back.
fallback := false
select {
case <-ctx.Done():
default:
if fallbackErr, ok := err.(fallbackError); ok {
fallback = true
if fallbackErr.transportOK && endpoint.URL.Scheme == "https" {
confirmedTLSRegistries[endpoint.URL.Host] = struct{}{}
}
err = fallbackErr.err
}
}
if fallback {
lastErr = err
log.G(ctx).Infof("Attempting next endpoint for pull after error: %v", err)
continue
}
log.G(ctx).Errorf("Not continuing with pull after error: %v", err)
return repoInfo, translatePullError(err, ref)
}
return repoInfo, nil
}
if lastErr == nil {
lastErr = fmt.Errorf("no endpoints found for %s", reference.FamiliarString(ref))
}
return repoInfo, translatePullError(lastErr, ref)
}

View file

@ -86,18 +86,7 @@ func (p *puller) pull(ctx context.Context, ref reference.Named) (err error) {
return err
}
if err = p.pullRepository(ctx, ref); err != nil {
if _, ok := err.(fallbackError); ok {
return err
}
if continueOnError(err, p.endpoint.Mirror) {
return fallbackError{
err: err,
transportOK: true,
}
}
}
return err
return p.pullRepository(ctx, ref)
}
func (p *puller) pullRepository(ctx context.Context, ref reference.Named) (err error) {