Support pagination for tags

registry/tags.go

@@ -1,20 +1,38 @@
 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)
+	u := r.url("/v2/%s/tags/list", repository)
+	r.Logf("registry.tags url=%s repository=%s", u, repository)
 
 	var response tagsResponse
-	if _, err := r.getJSON(ctx, url, &response); err != nil {
+	h, err := r.getJSON(ctx, u, &response)
+	if err != nil {
 		return nil, err
 	}
+	tags := response.Tags
+
+	for _, l := range link.ParseHeader(h) {
+		if l.Rel == "next" {
+			unescaped, _ := url.QueryUnescape(l.URI)
+			h, err = r.getJSON(ctx, unescaped, &response)
+			if err != nil {
+				return nil, err
+			}
+			tags = append(tags, response.Tags...)
+		}
+	}
 
-	return response.Tags, nil
+	return tags, nil
 }