Implement NearbyDevice::ToProto() for Connections device

PiperOrigin-RevId: 546376155

connections/v3/BUILD

@@ -1,5 +1,8 @@
 cc_library(
     name = "v3_types",
+    srcs = [
+        "connections_device.cc",
+    ],
     hdrs = [
         "bandwidth_info.h",
         "connection_listening_options.h",
@@ -15,11 +18,13 @@ cc_library(
     ],
     deps = [
         "//connections:core_types",
+        "//connections/implementation/proto:offline_wire_formats_cc_proto",
         "//internal/crypto",
         "//internal/interop:device",
         "//internal/platform:connection_info",
         "//proto:connections_enums_cc_proto",
         "@com_google_absl//absl/functional:any_invocable",
+        "@com_google_absl//absl/strings",
     ],
 )
 
@@ -30,8 +35,8 @@ cc_test(
         "connections_device_test.cc",
     ],
     deps = [
-        "//connections/implementation:internal_test",
-        "//connections/v3:v3_types",
+        ":v3_types",
+        "//connections/implementation/proto:offline_wire_formats_cc_proto",
         "//internal/platform:connection_info",
         "//internal/platform/implementation/g3",  # build_cleaner: keep
         "@com_github_protobuf_matchers//protobuf-matchers",

connections/v3/connections_device.cc

@@ -0,0 +1,63 @@
+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "connections/v3/connections_device.h"
+
+#include <string>
+#include <variant>
+
+#include "absl/strings/str_cat.h"
+#include "connections/implementation/proto/offline_wire_formats.pb.h"
+#include "internal/platform/ble_connection_info.h"
+#include "internal/platform/bluetooth_connection_info.h"
+#include "internal/platform/wifi_lan_connection_info.h"
+
+namespace nearby {
+namespace connections {
+namespace v3 {
+
+std::string ConnectionsDevice::ToProtoBytes() const {
+  // Bytes holding the connection info data elements.
+  std::string connection_info_string;
+  for (const auto& connection_info : connection_infos_) {
+    if (std::holds_alternative<absl::monostate>(connection_info)) {
+      continue;
+    }
+    if (std::holds_alternative<BleConnectionInfo>(connection_info)) {
+      absl::StrAppend(
+          &connection_info_string,
+          std::get<BleConnectionInfo>(connection_info).ToDataElementBytes());
+    }
+    if (std::holds_alternative<WifiLanConnectionInfo>(connection_info)) {
+      absl::StrAppend(&connection_info_string,
+                      std::get<WifiLanConnectionInfo>(connection_info)
+                          .ToDataElementBytes());
+    }
+    if (std::holds_alternative<BluetoothConnectionInfo>(connection_info)) {
+      absl::StrAppend(&connection_info_string,
+                      std::get<BluetoothConnectionInfo>(connection_info)
+                          .ToDataElementBytes());
+    }
+  }
+  location::nearby::connections::ConnectionsDevice device_frame;
+  device_frame.set_endpoint_id(endpoint_id_);
+  device_frame.set_endpoint_info(endpoint_info_);
+  device_frame.set_connectivity_info_list(connection_info_string);
+  device_frame.set_endpoint_type(
+      location::nearby::connections::CONNECTIONS_ENDPOINT);
+  return device_frame.SerializeAsString();
+}
+}  // namespace v3
+}  // namespace connections
+}  // namespace nearby

connections/v3/connections_device.h

@@ -54,8 +54,7 @@ class ConnectionsDevice : public nearby::NearbyDevice {
   Type GetType() const override { return Type::kConnectionsDevice; }
 
   std::string GetEndpointInfo() const { return endpoint_info_; }
-  // TODO(b/289368652): Implement.
-  std::string ToProtoBytes() const override { return ""; }
+  std::string ToProtoBytes() const override;
 
  private:
   std::string GenerateRandomEndpointId() {

connections/v3/connections_device_test.cc

@@ -19,6 +19,7 @@
 #include "gmock/gmock.h"
 #include "protobuf-matchers/protocol-buffer-matchers.h"
 #include "gtest/gtest.h"
+#include "connections/implementation/proto/offline_wire_formats.pb.h"
 #include "internal/platform/ble_connection_info.h"
 #include "internal/platform/connection_info.h"
 #include "internal/platform/wifi_lan_connection_info.h"
@@ -64,6 +65,19 @@ TEST(ConnectionsDeviceTest, TestLongEndpointId) {
   EXPECT_EQ(device.GetEndpointInfo(), "connections endpoint");
 }
 
+TEST(ConnectionsDeviceTest, TestToProtoBytes) {
+  auto connection_infos = CreateDefaultConnectionInfos();
+  ConnectionsDevice device("ABCD", "connections endpoint", connection_infos);
+  auto proto_bytes = device.ToProtoBytes();
+  location::nearby::connections::ConnectionsDevice device_frame;
+  ASSERT_TRUE(device_frame.ParseFromString(proto_bytes));
+  EXPECT_EQ(device_frame.endpoint_id(), "ABCD");
+  EXPECT_EQ(device_frame.endpoint_info(), "connections endpoint");
+  EXPECT_TRUE(device_frame.has_connectivity_info_list());
+  EXPECT_EQ(device_frame.endpoint_type(),
+            location::nearby::connections::CONNECTIONS_ENDPOINT);
+}
+
 }  // namespace
 }  // namespace v3
 }  // namespace connections