From 08426ad10debbc46e922334c3890f76950024713 Mon Sep 17 00:00:00 2001
From: Yong Tang <yong.tang.github@outlook.com>
Date: Wed, 1 Jun 2016 13:38:14 -0700
Subject: [PATCH] Add `--limit` option to `docker search`

This fix tries to address the issue raised in #23055.
Currently `docker search` result caps at 25 and there is
no way to allow getting more results (if exist).

This fix adds the flag `--limit` so that it is possible
to return more results from the `docker search`.

Related documentation has been updated.

Additional tests have been added to cover the changes.

This fix fixes #23055.

Signed-off-by: Yong Tang <yong.tang.github@outlook.com>
---
 docs/registry_test.go |  2 +-
 docs/service.go       | 13 +++++++++----
 docs/session.go       |  7 +++++--
 3 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/docs/registry_test.go b/docs/registry_test.go
index 39a01bcd4..9927af32d 100644
--- a/docs/registry_test.go
+++ b/docs/registry_test.go
@@ -730,7 +730,7 @@ func TestPushImageJSONIndex(t *testing.T) {
 
 func TestSearchRepositories(t *testing.T) {
 	r := spawnTestRegistrySession(t)
-	results, err := r.SearchRepositories("fakequery")
+	results, err := r.SearchRepositories("fakequery", 25)
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/docs/service.go b/docs/service.go
index d48063cd7..25b4990e8 100644
--- a/docs/service.go
+++ b/docs/service.go
@@ -15,6 +15,11 @@ import (
 	registrytypes "github.com/docker/engine-api/types/registry"
 )
 
+const (
+	// DefaultSearchLimit is the default value for maximum number of returned search results.
+	DefaultSearchLimit = 25
+)
+
 // Service is the interface defining what a registry service should implement.
 type Service interface {
 	Auth(ctx context.Context, authConfig *types.AuthConfig, userAgent string) (status, token string, err error)
@@ -22,7 +27,7 @@ type Service interface {
 	LookupPushEndpoints(hostname string) (endpoints []APIEndpoint, err error)
 	ResolveRepository(name reference.Named) (*RepositoryInfo, error)
 	ResolveIndex(name string) (*registrytypes.IndexInfo, error)
-	Search(ctx context.Context, term string, authConfig *types.AuthConfig, userAgent string, headers map[string][]string) (*registrytypes.SearchResults, error)
+	Search(ctx context.Context, term string, limit int, authConfig *types.AuthConfig, userAgent string, headers map[string][]string) (*registrytypes.SearchResults, error)
 	ServiceConfig() *registrytypes.ServiceConfig
 	TLSConfig(hostname string) (*tls.Config, error)
 }
@@ -108,7 +113,7 @@ func splitReposSearchTerm(reposName string) (string, string) {
 
 // Search queries the public registry for images matching the specified
 // search terms, and returns the results.
-func (s *DefaultService) Search(ctx context.Context, term string, authConfig *types.AuthConfig, userAgent string, headers map[string][]string) (*registrytypes.SearchResults, error) {
+func (s *DefaultService) Search(ctx context.Context, term string, limit int, authConfig *types.AuthConfig, userAgent string, headers map[string][]string) (*registrytypes.SearchResults, error) {
 	// TODO Use ctx when searching for repositories
 	if err := validateNoScheme(term); err != nil {
 		return nil, err
@@ -139,9 +144,9 @@ func (s *DefaultService) Search(ctx context.Context, term string, authConfig *ty
 			localName = strings.SplitN(localName, "/", 2)[1]
 		}
 
-		return r.SearchRepositories(localName)
+		return r.SearchRepositories(localName, limit)
 	}
-	return r.SearchRepositories(remoteName)
+	return r.SearchRepositories(remoteName, limit)
 }
 
 // ResolveRepository splits a repository name into its components
diff --git a/docs/session.go b/docs/session.go
index 82593cd7e..140c458eb 100644
--- a/docs/session.go
+++ b/docs/session.go
@@ -721,9 +721,12 @@ func shouldRedirect(response *http.Response) bool {
 }
 
 // SearchRepositories performs a search against the remote repository
-func (r *Session) SearchRepositories(term string) (*registrytypes.SearchResults, error) {
+func (r *Session) SearchRepositories(term string, limit int) (*registrytypes.SearchResults, error) {
+	if limit < 1 || limit > 100 {
+		return nil, fmt.Errorf("Limit %d is outside the range of [1, 100]", limit)
+	}
 	logrus.Debugf("Index server: %s", r.indexEndpoint)
-	u := r.indexEndpoint.String() + "search?q=" + url.QueryEscape(term)
+	u := r.indexEndpoint.String() + "search?q=" + url.QueryEscape(term) + "&n=" + url.QueryEscape(fmt.Sprintf("%d", limit))
 
 	req, err := http.NewRequest("GET", u, nil)
 	if err != nil {