1 files changed, 154 insertions, 0 deletions
diff --git a/pkg/v1/remote/catalog.go b/pkg/v1/remote/catalog.go
new file mode 100644
index 0000000..eb4306f
--- /dev/null
+++ b/pkg/v1/remote/catalog.go
@@ -0,0 +1,154 @@
+// Copyright 2019 Google LLC All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package remote
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/url"
+
+	"github.com/google/go-containerregistry/pkg/name"
+	"github.com/google/go-containerregistry/pkg/v1/remote/transport"
+)
+
+type catalog struct {
+	Repos []string `json:"repositories"`
+}
+
+// CatalogPage calls /_catalog, returning the list of repositories on the registry.
+func CatalogPage(target name.Registry, last string, n int, options ...Option) ([]string, error) {
+	o, err := makeOptions(target, options...)
+	if err != nil {
+		return nil, err
+	}
+
+	scopes := []string{target.Scope(transport.PullScope)}
+	tr, err := transport.NewWithContext(o.context, target, o.auth, o.transport, scopes)
+	if err != nil {
+		return nil, err
+	}
+
+	query := fmt.Sprintf("last=%s&n=%d", url.QueryEscape(last), n)
+
+	uri := url.URL{
+		Scheme:   target.Scheme(),
+		Host:     target.RegistryStr(),
+		Path:     "/v2/_catalog",
+		RawQuery: query,
+	}
+
+	client := http.Client{Transport: tr}
+	req, err := http.NewRequest(http.MethodGet, uri.String(), nil)
+	if err != nil {
+		return nil, err
+	}
+	resp, err := client.Do(req.WithContext(o.context))
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	if err := transport.CheckError(resp, http.StatusOK); err != nil {
+		return nil, err
+	}
+
+	var parsed catalog
+	if err := json.NewDecoder(resp.Body).Decode(&parsed); err != nil {
+		return nil, err
+	}
+
+	return parsed.Repos, nil
+}
+
+// Catalog calls /_catalog, returning the list of repositories on the registry.
+func Catalog(ctx context.Context, target name.Registry, options ...Option) ([]string, error) {
+	o, err := makeOptions(target, options...)
+	if err != nil {
+		return nil, err
+	}
+
+	scopes := []string{target.Scope(transport.PullScope)}
+	tr, err := transport.NewWithContext(o.context, target, o.auth, o.transport, scopes)
+	if err != nil {
+		return nil, err
+	}
+
+	uri := &url.URL{
+		Scheme: target.Scheme(),
+		Host:   target.RegistryStr(),
+		Path:   "/v2/_catalog",
+	}
+
+	if o.pageSize > 0 {
+		uri.RawQuery = fmt.Sprintf("n=%d", o.pageSize)
+	}
+
+	client := http.Client{Transport: tr}
+
+	// WithContext overrides the ctx passed directly.
+	if o.context != context.Background() {
+		ctx = o.context
+	}
+
+	var (
+		parsed   catalog
+		repoList []string
+	)
+
+	// get responses until there is no next page
+	for {
+		select {
+		case <-ctx.Done():
+			return nil, ctx.Err()
+		default:
+		}
+
+		req, err := http.NewRequest("GET", uri.String(), nil)
+		if err != nil {
+			return nil, err
+		}
+		req = req.WithContext(ctx)
+
+		resp, err := client.Do(req)
+		if err != nil {
+			return nil, err
+		}
+
+		if err := transport.CheckError(resp, http.StatusOK); err != nil {
+			return nil, err
+		}
+
+		if err := json.NewDecoder(resp.Body).Decode(&parsed); err != nil {
+			return nil, err
+		}
+		if err := resp.Body.Close(); err != nil {
+			return nil, err
+		}
+
+		repoList = append(repoList, parsed.Repos...)
+
+		uri, err = getNextPageURL(resp)
+		if err != nil {
+			return nil, err
+		}
+		// no next page
+		if uri == nil {
+			break
+		}
+	}
+	return repoList, nil
+}