fix: fix 1000+ buckets pagination issue (#15112)

* test: add unit test to confirm absence of pageToken param in listBuckets request, which causes the 1000+ buckets infinite pagination loop

* test: add unit test to confirm absence of pageToken param in listBuckets request, which causes the 1000+ buckets infinite pagination loop

* test: add unit test to confirm absence of pageToken param in listBuckets request, which causes the 1000+ buckets infinite pagination loop

* test: add unit test to confirm absence of pageToken param in listBuckets request, which causes the 1000+ buckets infinite pagination loop

* test: add unit test to confirm absence of pageToken param in listBuckets request, which causes the 1000+ buckets infinite pagination loop

* test: add unit test to confirm absence of pageToken param in listBuckets request, which causes the 1000+ buckets infinite pagination loop

---------

Co-authored-by: Denis DelGrosso <[email protected]>

Author: eliekozah

google/cloud/storage/internal/rest/stub.cc

@@ -183,6 +183,9 @@ StatusOr<ListBucketsResponse> RestStub::ListBuckets(
   if (!headers.ok()) return headers;
   request.AddOptionsToHttpRequest(builder);
   builder.AddQueryParameter("project", request.project_id());
+  if (!request.page_token().empty()) {
+    builder.AddQueryParameter("pageToken", request.page_token());
+  }
   return ParseFromRestResponse<ListBucketsResponse>(
       storage_rest_client_->Get(context, std::move(builder).BuildRequest()));
 }

google/cloud/storage/internal/rest/stub_test.cc

@@ -40,6 +40,7 @@ using ::testing::ElementsAre;
 using ::testing::Eq;
 using ::testing::HasSubstr;
 using ::testing::Matcher;
+using ::testing::Not;
 using ::testing::Pair;
 using ::testing::ResultOf;
 using ::testing::Return;
@@ -193,6 +194,42 @@ TEST(RestStubTest, CreateBucket) {
               StatusIs(PermanentError().code(), PermanentError().message()));
 }
 
+TEST(RestStubTest, ListBucketsIncludesPageTokenWhenPresentInRequest) {
+  auto mock = std::make_shared<MockRestClient>();
+  std::string expected_token = "test-page-token";
+  ListBucketsRequest request("test-project-id");
+  request.set_page_token(expected_token);
+
+  EXPECT_CALL(*mock,
+              Get(ExpectedContext(),
+                  ResultOf(
+                      "request parameters contain 'pageToken'",
+                      [](RestRequest const& r) { return r.parameters(); },
+                      Contains(Pair("pageToken", expected_token)))))
+      .WillOnce(Return(PermanentError()));
+
+  auto tested = std::make_unique<RestStub>(Options{}, mock, mock);
+  auto context = TestContext();
+  tested->ListBuckets(context, TestOptions(), request);
+}
+
+TEST(RestStubTest, ListBucketsOmitsPageTokenWhenEmptyInRequest) {
+  auto mock = std::make_shared<MockRestClient>();
+  ListBucketsRequest request("test-project-id");
+
+  EXPECT_CALL(*mock,
+              Get(ExpectedContext(),
+                  ResultOf(
+                      "request parameters do not contain 'pageToken'",
+                      [](RestRequest const& r) { return r.parameters(); },
+                      Not(Contains(Pair("pageToken", _))))))
+      .WillOnce(Return(PermanentError()));
+
+  auto tested = std::make_unique<RestStub>(Options{}, mock, mock);
+  auto context = TestContext();
+  tested->ListBuckets(context, TestOptions(), request);
+}
+
 TEST(RestStubTest, GetBucketMetadata) {
   auto mock = std::make_shared<MockRestClient>();
   EXPECT_CALL(*mock, Get(ExpectedContext(), ExpectedRequest()))