Support pagination for tags

registry/tags.go

@@ -1,20 +1,46 @@
 package registry
 
-import "context"
+import (
+	"context"
+	"net/url"
+
+	"github.com/peterhellberg/link"
+)
 
 type tagsResponse struct {
 	Tags []string `json:"tags"`
 }
 
-// Tags returns the tags for a specific repository.
-func (r *Registry) Tags(ctx context.Context, repository string) ([]string, error) {
-	url := r.url("/v2/%s/tags/list", repository)
-	r.Logf("registry.tags url=%s repository=%s", url, repository)
+func (r *Registry) tags(ctx context.Context, u string, repository string) ([]string, error) {
+	var uri string
+	if u == "" {
+		r.Logf("registry.tags url=%s repository=%s", u, repository)
+		uri = r.url("/v2/%s/tags/list", repository)
+	} else {
+		uri = r.url(u)
+	}
 
 	var response tagsResponse
-	if _, err := r.getJSON(ctx, url, &response); err != nil {
+	h, err := r.getJSON(ctx, uri, &response)
+	if err != nil {
 		return nil, err
 	}
 
+	for _, l := range link.ParseHeader(h) {
+		if l.Rel == "next" {
+			unescaped, _ := url.QueryUnescape(l.URI)
+			tags, err := r.tags(ctx, unescaped, repository)
+			if err != nil {
+				return nil, err
+			}
+			response.Tags = append(response.Tags, tags...)
+		}
+	}
+
 	return response.Tags, nil
 }
+
+// Tags returns the tags for a specific repository.
+func (r *Registry) Tags(ctx context.Context, repository string) ([]string, error) {
+	return r.tags(ctx, "", repository)
+}