From 5ff724e44e0b19745e1a4ca414d0f8b64c4ea2ad Mon Sep 17 00:00:00 2001
From: Zijie Li <zijieli@google.com>
Date: Mon, 11 May 2026 15:24:10 -0400
Subject: [PATCH] fix(bigtable): use `google-c2p://` as the Bigtable DirectPath
 endpoint

Fix to use the correct Bigtable DirectPath endpoint.
---
 google/cloud/bigtable/internal/defaults.cc      |  2 +-
 google/cloud/bigtable/internal/defaults_test.cc | 10 ++++++----
 2 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/google/cloud/bigtable/internal/defaults.cc b/google/cloud/bigtable/internal/defaults.cc
index 2fa2a0da70fea..ff71df2383cba 100644
--- a/google/cloud/bigtable/internal/defaults.cc
+++ b/google/cloud/bigtable/internal/defaults.cc
@@ -186,7 +186,7 @@ Options DefaultOptions(Options opts) {
   // Set the specific data endpoints if Direct Path is enabled.
   if (IsDirectPath()) {
     opts.set<::google::cloud::bigtable_internal::DataEndpointOption>(
-            "c2p:///bigtable.googleapis.com")
+            "google-c2p:///bigtable.googleapis.com")
         .set<AuthorityOption>("bigtable.googleapis.com");
   }
 
diff --git a/google/cloud/bigtable/internal/defaults_test.cc b/google/cloud/bigtable/internal/defaults_test.cc
index 78f6b3512e9ea..574c5f014b05b 100644
--- a/google/cloud/bigtable/internal/defaults_test.cc
+++ b/google/cloud/bigtable/internal/defaults_test.cc
@@ -504,7 +504,7 @@ TEST(EndpointEnvTest, CloudDirectPathEnabled) {
   ScopedEnvironment cbt_direct_path("CBT_ENABLE_DIRECTPATH", absl::nullopt);
 
   auto opts = DefaultOptions();
-  EXPECT_EQ("c2p:///bigtable.googleapis.com",
+  EXPECT_EQ("google-c2p:///bigtable.googleapis.com",
             opts.get<::google::cloud::bigtable_internal::DataEndpointOption>());
   EXPECT_EQ("bigtable.googleapis.com", opts.get<AuthorityOption>());
   // Admin endpoints are not affected.
@@ -525,7 +525,7 @@ TEST(EndpointEnvTest, BigtableDirectPathEnabled) {
   ScopedEnvironment cbt_direct_path("CBT_ENABLE_DIRECTPATH", "true");
 
   auto opts = DefaultOptions();
-  EXPECT_EQ("c2p:///bigtable.googleapis.com",
+  EXPECT_EQ("google-c2p:///bigtable.googleapis.com",
             opts.get<::google::cloud::bigtable_internal::DataEndpointOption>());
   EXPECT_EQ("bigtable.googleapis.com", opts.get<AuthorityOption>());
   // Admin endpoints are not affected.
@@ -564,7 +564,8 @@ TEST(EndpointEnvTest, CloudDirectPathOverridesUserEndpoints) {
 
   auto opts = DefaultDataOptions(
       Options{}.set<EndpointOption>("ignored").set<AuthorityOption>("ignored"));
-  EXPECT_EQ("c2p:///bigtable.googleapis.com", opts.get<EndpointOption>());
+  EXPECT_EQ("google-c2p:///bigtable.googleapis.com",
+            opts.get<EndpointOption>());
   EXPECT_EQ("bigtable.googleapis.com", opts.get<AuthorityOption>());
 }
 
@@ -574,7 +575,8 @@ TEST(EndpointEnvTest, BigtableDirectPathOverridesUserEndpoints) {
 
   auto opts = DefaultDataOptions(
       Options{}.set<EndpointOption>("ignored").set<AuthorityOption>("ignored"));
-  EXPECT_EQ("c2p:///bigtable.googleapis.com", opts.get<EndpointOption>());
+  EXPECT_EQ("google-c2p:///bigtable.googleapis.com",
+            opts.get<EndpointOption>());
   EXPECT_EQ("bigtable.googleapis.com", opts.get<AuthorityOption>());
 }