Build correct URL for cacheinvalidation endpoint.

Build URL for sending client-to-server cacheinvalidation messages.

BUG=325020
R=rlarocque@chromium.org

Review URL: https://codereview.chromium.org/182333003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@255825 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 154 insertions, 21 deletions

diff --git a/sync/notifier/gcm_network_channel.cc b/sync/notifier/gcm_network_channel.cc
index b4ea4bc..e0efda5 100644
--- a/sync/notifier/gcm_network_channel.cc
+++ b/sync/notifier/gcm_network_channel.cc
@@ -2,6 +2,15 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include "base/base64.h"
+#include "base/strings/string_util.h"
+#if !defined(ANDROID)
+// channel_common.proto defines ANDROID constant that conflicts with Android
+// build. At the same time TiclInvalidationService is not used on Android so it
+// is safe to exclude these protos from Android build.
+#include "google/cacheinvalidation/android_channel.pb.h"
+#include "google/cacheinvalidation/channel_common.pb.h"
+#endif
 #include "google_apis/gaia/google_service_auth_error.h"
 #include "net/http/http_status_code.h"
 #include "net/url_request/url_fetcher.h"
@@ -13,6 +22,10 @@ namespace syncer {
 
 namespace {
 
+const char kCacheInvalidationEndpointUrl[] =
+    "https://clients4.google.com/invalidation/android/request/";
+const char kCacheInvalidationPackageName[] = "com.google.chrome.invalidations";
+
 // Register backoff policy.
 const net::BackoffEntry::Policy kRegisterBackoffPolicy = {
   // Number of initial errors (in sequence) to ignore before applying
@@ -143,9 +156,8 @@ void GCMNetworkChannel::OnGetTokenComplete(
   access_token_ = token;
 
   DVLOG(2) << "Got access token, sending message";
-
-  fetcher_.reset(net::URLFetcher::Create(BuildUrl(), net::URLFetcher::POST,
-                                         this));
+  fetcher_.reset(net::URLFetcher::Create(
+      BuildUrl(registration_id_), net::URLFetcher::POST, this));
   fetcher_->SetRequestContext(request_context_getter_);
   const std::string auth_header("Authorization: Bearer " + access_token_);
   fetcher_->AddExtraRequestHeader(auth_header);
@@ -175,13 +187,62 @@ void GCMNetworkChannel::OnURLFetchComplete(const net::URLFetcher* source) {
   DVLOG(2) << "URLFetcher success";
 }
 
-GURL GCMNetworkChannel::BuildUrl() {
-  DCHECK(!registration_id_.empty());
-  // Prepare NetworkEndpointId using registration_id
-  // Serialize NetworkEndpointId into byte array and base64 encode.
-  // Format url using encoded NetworkEndpointId.
-  // TODO(pavely): implement all of the above.
-  return GURL("http://invalid.url.com");
+GURL GCMNetworkChannel::BuildUrl(const std::string& registration_id) {
+  DCHECK(!registration_id.empty());
+
+#if !defined(ANDROID)
+  ipc::invalidation::EndpointId endpoint_id;
+  endpoint_id.set_c2dm_registration_id(registration_id);
+  endpoint_id.set_client_key(std::string());
+  endpoint_id.set_package_name(kCacheInvalidationPackageName);
+  endpoint_id.mutable_channel_version()->set_major_version(
+      ipc::invalidation::INITIAL);
+  std::string endpoint_id_buffer;
+  endpoint_id.SerializeToString(&endpoint_id_buffer);
+
+  ipc::invalidation::NetworkEndpointId network_endpoint_id;
+  network_endpoint_id.set_network_address(
+      ipc::invalidation::NetworkEndpointId_NetworkAddress_ANDROID);
+  network_endpoint_id.set_client_address(endpoint_id_buffer);
+  std::string network_endpoint_id_buffer;
+  network_endpoint_id.SerializeToString(&network_endpoint_id_buffer);
+
+  std::string base64URLPiece;
+  Base64EncodeURLSafe(network_endpoint_id_buffer, &base64URLPiece);
+
+  std::string url(kCacheInvalidationEndpointUrl);
+  url += base64URLPiece;
+  return GURL(url);
+#else
+  // This code shouldn't be invoked on Android.
+  NOTREACHED();
+  return GURL();
+#endif
+}
+
+void GCMNetworkChannel::Base64EncodeURLSafe(const std::string& input,
+                                            std::string* output) {
+  base::Base64Encode(input, output);
+  // Covert to url safe alphabet.
+  base::ReplaceChars(*output, "+", "-", output);
+  base::ReplaceChars(*output, "/", "_", output);
+  // Trim padding.
+  size_t padding_size = 0;
+  for (size_t i = output->size(); i > 0 && (*output)[i - 1] == '='; --i)
+    ++padding_size;
+  output->resize(output->size() - padding_size);
+}
+
+bool GCMNetworkChannel::Base64DecodeURLSafe(const std::string& input,
+                                            std::string* output) {
+  // Add padding.
+  size_t padded_size = (input.size() + 3) - (input.size() + 3) % 4;
+  std::string padded_input(input);
+  padded_input.resize(padded_size, '=');
+  // Convert to standard base64 alphabet.
+  base::ReplaceChars(padded_input, "-", "+", &padded_input);
+  base::ReplaceChars(padded_input, "_", "/", &padded_input);
+  return base::Base64Decode(padded_input, output);
 }
 
 }  // namespace syncer
diff --git a/sync/notifier/gcm_network_channel.h b/sync/notifier/gcm_network_channel.h
index 0dd64ee..4b50dc9 100644
--- a/sync/notifier/gcm_network_channel.h
+++ b/sync/notifier/gcm_network_channel.h
@@ -49,14 +49,22 @@ class SYNC_EXPORT_PRIVATE GCMNetworkChannel
   void ResetRegisterBackoffEntryForTest(
       const net::BackoffEntry::Policy* policy);
 
+  virtual GURL BuildUrl(const std::string& registration_id);
+
  private:
+  friend class GCMNetworkChannelTest;
   void Register();
   void OnRegisterComplete(const std::string& registration_id,
                           gcm::GCMClient::Result result);
   void RequestAccessToken();
   void OnGetTokenComplete(const GoogleServiceAuthError& error,
                           const std::string& token);
-  GURL BuildUrl();
+  // Base64 encoding/decoding with URL safe alphabet.
+  // http://tools.ietf.org/html/rfc4648#page-7
+  static void Base64EncodeURLSafe(const std::string& input,
+                                  std::string* output);
+  static bool Base64DecodeURLSafe(const std::string& input,
+                                  std::string* output);
 
   scoped_refptr<net::URLRequestContextGetter> request_context_getter_;
   scoped_ptr<GCMNetworkChannelDelegate> delegate_;
diff --git a/sync/notifier/gcm_network_channel_unittest.cc b/sync/notifier/gcm_network_channel_unittest.cc
index a8ef9ac..00fc5dc 100644
--- a/sync/notifier/gcm_network_channel_unittest.cc
+++ b/sync/notifier/gcm_network_channel_unittest.cc
@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 #include "base/run_loop.h"
+#include "base/strings/string_util.h"
 #include "google_apis/gaia/google_service_auth_error.h"
 #include "net/url_request/test_url_fetcher_factory.h"
 #include "net/url_request/url_request_test_util.h"
@@ -10,7 +11,6 @@
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace syncer {
-namespace {
 
 class TestGCMNetworkChannelDelegate : public GCMNetworkChannelDelegate {
  public:
@@ -73,6 +73,13 @@ class TestGCMNetworkChannel : public GCMNetworkChannel {
       :  GCMNetworkChannel(request_context_getter, delegate.Pass()) {
     ResetRegisterBackoffEntryForTest(&kTestBackoffPolicy);
   }
+
+ protected:
+  // On Android GCMNetworkChannel::BuildUrl hits NOTREACHED(). I still want
+  // tests to run.
+  virtual GURL BuildUrl(const std::string& registration_id) OVERRIDE {
+    return GURL("http://test.url.com");
+  }
 };
 
 class GCMNetworkChannelTest
@@ -110,6 +117,21 @@ class GCMNetworkChannelTest
     gcm_network_channel_->RemoveObserver(this);
   }
 
+  // Helper functions to call private methods from test
+  GURL BuildUrl(const std::string& registration_id) {
+    return gcm_network_channel_->GCMNetworkChannel::BuildUrl(registration_id);
+  }
+
+  static void Base64EncodeURLSafe(const std::string& input,
+                                  std::string* output) {
+    GCMNetworkChannel::Base64EncodeURLSafe(input, output);
+  }
+
+  static bool Base64DecodeURLSafe(const std::string& input,
+                                  std::string* output) {
+    return GCMNetworkChannel::Base64DecodeURLSafe(input, output);
+  }
+
   virtual void OnNetworkChannelStateChanged(
       InvalidatorState invalidator_state) OVERRIDE {
   }
@@ -159,8 +181,9 @@ class GCMNetworkChannelTest
 };
 
 TEST_F(GCMNetworkChannelTest, HappyCase) {
-  GURL url("http://invalid.url.com");
-  url_fetcher_factory()->SetFakeResponse(url, std::string(), net::HTTP_OK,
+  url_fetcher_factory()->SetFakeResponse(GURL("http://test.url.com"),
+                                         std::string(),
+                                         net::HTTP_OK,
                                          net::URLRequestStatus::SUCCESS);
 
   // After construction GCMNetworkChannel should have called Register.
@@ -209,9 +232,10 @@ TEST_F(GCMNetworkChannelTest, FailedRegister) {
 }
 
 TEST_F(GCMNetworkChannelTest, RegisterFinishesAfterSendMessage) {
-  GURL url("http://invalid.url.com");
-  url_fetcher_factory()->SetFakeResponse(url, "", net::HTTP_OK,
-      net::URLRequestStatus::SUCCESS);
+  url_fetcher_factory()->SetFakeResponse(GURL("http://test.url.com"),
+                                         "",
+                                         net::HTTP_OK,
+                                         net::URLRequestStatus::SUCCESS);
 
   // After construction GCMNetworkChannel should have called Register.
   EXPECT_FALSE(delegate()->register_callback.is_null());
@@ -254,9 +278,10 @@ TEST_F(GCMNetworkChannelTest, RequestTokenFailure) {
 
 TEST_F(GCMNetworkChannelTest, AuthErrorFromServer) {
   // Setup fake response to return AUTH_ERROR.
-  GURL url("http://invalid.url.com");
-  url_fetcher_factory()->SetFakeResponse(url, "", net::HTTP_UNAUTHORIZED,
-      net::URLRequestStatus::SUCCESS);
+  url_fetcher_factory()->SetFakeResponse(GURL("http://test.url.com"),
+                                         "",
+                                         net::HTTP_UNAUTHORIZED,
+                                         net::URLRequestStatus::SUCCESS);
 
   // After construction GCMNetworkChannel should have called Register.
   EXPECT_FALSE(delegate()->register_callback.is_null());
@@ -293,5 +318,44 @@ TEST_F(GCMNetworkChannelTest, RequestTokenNeverCompletes) {
   EXPECT_FALSE(delegate()->request_token_callback.is_null());
 }
 
-}  // namespace
+#if !defined(ANDROID)
+TEST_F(GCMNetworkChannelTest, BuildUrl) {
+  GURL url = BuildUrl("registration.id");
+  EXPECT_TRUE(url.SchemeIsHTTPOrHTTPS());
+  EXPECT_FALSE(url.host().empty());
+  EXPECT_FALSE(url.path().empty());
+  std::vector<std::string> parts;
+  Tokenize(url.path(), "/", &parts);
+  std::string buffer;
+  EXPECT_TRUE(Base64DecodeURLSafe(parts[parts.size() - 1], &buffer));
+}
+#endif
+
+TEST_F(GCMNetworkChannelTest, Base64EncodeDecode) {
+  std::string input;
+  std::string plain;
+  std::string base64;
+  // Empty string.
+  Base64EncodeURLSafe(input, &base64);
+  EXPECT_TRUE(base64.empty());
+  EXPECT_TRUE(Base64DecodeURLSafe(base64, &plain));
+  EXPECT_EQ(input, plain);
+  // String length: 1..7.
+  for (int length = 1; length < 8; length++) {
+    input = "abra.cadabra";
+    input.resize(length);
+    Base64EncodeURLSafe(input, &base64);
+    // Ensure no padding at the end.
+    EXPECT_NE(base64[base64.size() - 1], '=');
+    EXPECT_TRUE(Base64DecodeURLSafe(base64, &plain));
+    EXPECT_EQ(input, plain);
+  }
+  // Presence of '-', '_'.
+  input = "\xfb\xff";
+  Base64EncodeURLSafe(input, &base64);
+  EXPECT_EQ("-_8", base64);
+  EXPECT_TRUE(Base64DecodeURLSafe(base64, &plain));
+  EXPECT_EQ(input, plain);
+}
+
 }  // namespace syncer