Fix test failures due to ipv4/ipv6 mismatch

cpp/example/routeguide/client.cc

@@ -220,7 +220,7 @@ class RouteGuideClient {
 };
 
 int main(int argc, char** argv) {
-  std::string server_address = routeguide::GetServerAddress();
+  std::string server_address = "127.0.0.1:" + routeguide::GetServerPort();
 
   std::cout << "Server Address: " << server_address << std::endl;
 

cpp/example/routeguide/helper.cc

@@ -44,14 +44,12 @@ std::string GetDbFileContent(int argc, char** argv) {
   return db.str();
 }
 
-std::string GetServerAddress() {
-  std::string server_host("0.0.0.0");
+std::string GetServerPort() {
   std::string server_port("50051");
   if (std::getenv("SERVER_PORT")) {
     server_port = std::getenv("SERVER_PORT");
   }
-  std::string server_address = server_host + ":" + server_port;
-  return server_address;
+  return server_port;
 }
 
 // A simple parser for the json db file. It requires the db file to have the

cpp/example/routeguide/helper.h

@@ -27,7 +27,7 @@ class Feature;
 
 std::string GetDbFileContent(int argc, char** argv);
 
-std::string GetServerAddress();
+std::string GetServerPort();
 
 void ParseDb(const std::string& db, std::vector<Feature>* feature_list);
 

cpp/example/routeguide/server.cc

@@ -168,7 +168,7 @@ class RouteGuideImpl final : public RouteGuide::Service {
 };
 
 void RunServer(const std::string& db_path) {
-  std::string server_address = routeguide::GetServerAddress();
+  std::string server_address = "[::]:" + routeguide::GetServerPort();
 
   RouteGuideImpl service(db_path);
 

rust/example/routeguide/server.rs

@@ -137,7 +137,7 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
         Err(_e) => 50051,
     };
 
-    let addr = format!("[::1]:{}", port).parse().unwrap();
+    let addr = format!("[::]:{}", port).parse().unwrap();
 
     println!("RouteGuideServer listening on: {}", addr);