feat(fdc): Added x-firebase-client header (#17015)

Author: maneesht

packages/firebase_data_connect/firebase_data_connect/lib/src/common/common_library.dart

@@ -29,6 +29,10 @@ String getGoogApiVal(CallerSDKType sdkType, String packageVersion) {
   return apiClientValue;
 }
 
+String getFirebaseClientVal(String packageVersion) {
+  return 'flutter-fire-dc/$packageVersion';
+}
+
 /// Transport Options for connecting to a specific host.
 class TransportOptions {
   /// Constructor

packages/firebase_data_connect/firebase_data_connect/lib/src/network/grpc_transport.dart

@@ -77,6 +77,7 @@ class GRPCTransport implements DataConnectTransport {
     Map<String, String> metadata = {
       'x-goog-request-params': 'location=${options.location}&frontend=data',
       'x-goog-api-client': getGoogApiVal(sdkType, packageVersion),
+      'x-firebase-client': getFirebaseClientVal(packageVersion)
     };
 
     if (authToken != null) {

packages/firebase_data_connect/firebase_data_connect/lib/src/network/rest_transport.dart

@@ -85,6 +85,7 @@ class RestTransport implements DataConnectTransport {
       'Content-Type': 'application/json',
       'Accept': 'application/json',
       'x-goog-api-client': getGoogApiVal(sdkType, packageVersion),
+      'x-firebase-client': getFirebaseClientVal(packageVersion)
     };
     String? appCheckToken;
     try {

packages/firebase_data_connect/firebase_data_connect/test/src/network/rest_transport_test.dart

@@ -17,6 +17,7 @@ import 'dart:convert';
 import 'package:firebase_app_check/firebase_app_check.dart';
 import 'package:firebase_auth/firebase_auth.dart';
 import 'package:firebase_data_connect/src/common/common_library.dart';
+import 'package:firebase_data_connect/src/dataconnect_version.dart';
 import 'package:firebase_data_connect/src/network/rest_library.dart';
 import 'package:flutter_test/flutter_test.dart';
 import 'package:http/http.dart' as http;
@@ -260,6 +261,42 @@ void main() {
         ),
       ).called(1);
     });
+    test('invokeOperation should include x-firebase-client headers', () async {
+      final mockResponse = http.Response('{"data": {"key": "value"}}', 200);
+      when(
+        mockHttpClient.post(
+          any,
+          headers: anyNamed('headers'),
+          body: anyNamed('body'),
+        ),
+      ).thenAnswer((_) async => mockResponse);
+
+      when(mockUser.getIdToken()).thenAnswer((_) async => 'authToken123');
+      when(mockAppCheck.getToken()).thenAnswer((_) async => 'appCheckToken123');
+
+      final deserializer = (String data) => 'Deserialized Data';
+
+      await transport.invokeOperation(
+        'testQuery',
+        'executeQuery',
+        deserializer,
+        null,
+        null,
+        'authToken123',
+      );
+
+      verify(
+        mockHttpClient.post(
+          any,
+          headers: argThat(
+            containsPair(
+                'x-firebase-client', getFirebaseClientVal(packageVersion)),
+            named: 'headers',
+          ),
+          body: anyNamed('body'),
+        ),
+      ).called(1);
+    });
 
     test(
         'invokeOperation should handle missing auth and appCheck tokens gracefully',