api_response_timer

A lightweight HTTP client wrapper that measures API response times with detailed timing metrics.

Features

• Wraps any http.Client using the standard BaseClient interface
• Measures elapsed time from request send to full response body received
• Captures URL, HTTP method, status code, response time, and response size
• Preserves original response behavior (response body remains fully readable)
• Uses deterministic timing with Stopwatch

Installation

Add to your pubspec.yaml:

dependencies:
  api_response_timer: ^0.1.0

Usage

import 'package:api_response_timer/api_response_timer.dart';

void main() async {
  final client = TimedClient(
    onComplete: (timing) {
      print('Request: ${timing.method} ${timing.url}');
      print('Status: ${timing.statusCode}');
      print('Response time: ${timing.responseTime.inMilliseconds}ms');
      print('Response size: ${timing.responseSize} bytes');
    },
  );

  final response = await client.get(Uri.parse('https://api.example.com/data'));
  print('Body: ${response.body}');

  client.close();
}

Using with an existing client

import 'package:http/http.dart' as http;
import 'package:api_response_timer/api_response_timer.dart';

void main() async {
  final innerClient = http.Client();

  final timedClient = TimedClient(
    inner: innerClient,
    onComplete: (timing) {
      print('${timing.method} ${timing.url} - ${timing.responseTime.inMilliseconds}ms');
    },
  );

  final response = await timedClient.post(
    Uri.parse('https://api.example.com/items'),
    body: '{"name": "test"}',
    headers: {'Content-Type': 'application/json'},
  );

  print('Created: ${response.body}');
  timedClient.close();
}

Collecting metrics

import 'package:api_response_timer/api_response_timer.dart';

class MetricsCollector {
  final List<ApiTiming> _timings = [];

  void record(ApiTiming timing) {
    _timings.add(timing);
  }

  double get averageResponseTimeMs {
    if (_timings.isEmpty) return 0;
    final total = _timings.fold<int>(
      0,
      (sum, t) => sum + t.responseTime.inMilliseconds,
    );
    return total / _timings.length;
  }
}

void main() async {
  final collector = MetricsCollector();

  final client = TimedClient(
    onComplete: collector.record,
  );

  await client.get(Uri.parse('https://api.example.com/users'));
  await client.get(Uri.parse('https://api.example.com/posts'));

  print('Average response time: ${collector.averageResponseTimeMs}ms');

  client.close();
}

API Reference

TimedClient

TimedClient({
  http.Client? inner,
  required OnTimingComplete onComplete,
})

• inner: Optional existing http.Client to wrap. If not provided, creates a new client.
• onComplete: Callback invoked after each request with timing metrics.

ApiTiming

Immutable data model containing:

License

MIT License