Flutter

Native Flutter SDK for Dart mobile apps.

Overview

The Flutter SDK provides realtime flag updates, polling fallback, identity targeting, and telemetry through the singleton Flags.

Get started

Install

YYAML

# pubspec.yaml
dependencies:
  truflag_flutter:
    path: <path-to-repo>/sdk/native/flutter/truflag_flutter

Configure

apiKey is required. If no user is passed, the SDK starts anonymous automatically.

DDART

import "package:truflag_flutter/truflag_flutter.dart";
 
await Flags.configure(
  apiKey: const String.fromEnvironment("TRUFLAG_CLIENT_KEY"),
  userId: "user-123",
  userAttributes: {
    "plan": "pro",
    "country": "US",
  },
);

SDK API overview

Full configure surface for Flutter.

DDART

Future<void> configure({
  required String apiKey,
  TruflagUser? user,
  String? userId,
  Map<String, dynamic>? userAttributes,
  TruflagStorage? storage,
  String baseUrl = "https://sdk.truflag.com",
  String streamUrl = "wss://stream.sdk.truflag.com",
  bool streamEnabled = true,
  TruflagLogLevel logLevel = TruflagLogLevel.debug,
  TruflagLogger? logger,
  TruflagFetchFn? fetchFn,
  int cacheTtlMs = 300000,
  int pollingIntervalMs = 60000,
  int requestTimeoutMs = 6000,
  bool telemetryEnabled = true,
  int telemetryFlushIntervalMs = 10000,
  int telemetryBatchSize = 50,
});

Identity

DDART

await Flags.login(
  userId: "user-456",
  attributes: {"plan": "enterprise"},
);
 
await Flags.setAttributes({
  "plan": "enterprise",
  "region": "us-east-1",
});
 
await Flags.logout(); // switches to anonymous user and refreshes

Flag reads

Use one read method: getFlag(key, fallback).

DDART

final enabled = Flags.getFlag("my-flag", false);
final variant = Flags.getFlag("checkout-variant", "control");
final config = Flags.getFlag("checkout-config", <String, dynamic>{});
 
final payload = Flags.getFlagPayload("my-flag");

Events

DDART

await Flags.track(
  "checkout_completed",
  properties: {
    "source": "flutter",
    "value": 99.95,
    "context": {"screen": "checkout"},
    "items": ["sku_1", "sku_2"],
  },
);
 
await Flags.expose("my-flag");

Reactive updates

watch() emits when flags/identity/diagnostics change, including websocket-driven updates.

DDART

final sub = Flags.watch().listen((snapshot) {
  final next = Flags.getFlag("my-flag", false);
  // update UI state here
});
 
// Later:
await sub.cancel();

Troubleshooting

Flags always return fallback

Confirm Flags.isReady is true and the flag key exists in the environment tied to your apiKey.

No realtime updates

Verify streamEnabled: true and a validstreamUrl. Polling fallback remains active if stream connectivity drops.