⏰ True Time Provider for Flutter

A secure and reliable time provider for Flutter apps. Fetches accurate time from NTP servers, with Firebase and device time as fallbacks.

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Screenshots

   

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Table of Contents

• Features
• Installation
• Usage
• How It Works
• Example Use Cases
• Configuration
• Limitations
• Roadmap
• License

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✨ Features

• ✅ Provides accurate, tamper-resistant current time
• ✅ Built-in Singleton pattern (global instance)
• ✅ Multi-source fallback (NTP → Firebase → Device)
• ✅ Handles network failures gracefully
• ✅ Supports IPv4 & IPv6
• ✅ Configurable NTP host, port, and timeout

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Installation

Add this to your pubspec.yaml:

dependencies:
  true_time_provider: latest_version

Install it with:

flutter pub get

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Usage

1. Initialize at app startup

void main() async {
  WidgetsFlutterBinding.ensureInitialized();

  // Initialize Firebase fallback
  TrueTimeProvider.instance.init(
    options: DefaultFirebaseOptions.currentPlatform,
  );

  runApp(MyApp());
}

2. Fetch secure time

final DateTime safeNow = await TrueTimeProvider.instance.now();
print("Secure current time: $safeNow");

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🛠 How It Works

Fallback Flow

try NTP server
   │
   ├── success → return ntpTime
   │
   └── fail → try Firebase
               │
               ├── success → return fireSTime
               │
               └── fail → return DateTime.now() (device)

Class Overview

• TrueTimeProvider → Singleton entry point
• NtpServerProvider → Fetches time via UDP NTP
• FirebaseCloudProvider → Fetches server time from Firestore
• Device Time → Final fallback

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⚡ Example Use Cases

• Banking / Payment apps
• Event logging / Audit trails
• Subscription & licensing apps
• Distributed systems

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🔧 Configuration

Override NTP lookup options:

final time = await TrueTimeProvider.instance.now(
  ntpFetchDuration: Duration(seconds: 20),
  ntoLookUpAddress: "pool.ntp.org",
  ntpLookupPort: 123,
);

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Limitations

• NTP requires UDP port 123 (may be blocked in some networks)
• Firebase fallback requires internet access
• Falls back to device time if both fail
• Currently only one NTP request per call (no retries)

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Roadmap

• Retry mechanism with exponential backoff
• Cache last known good offset
• Expose NTP sync statistics (delay, jitter)
• Add tests with mock NTP responses

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License

This project is licensed under the MIT License.

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