Cache

Introduction

Nylo Website v7 provides a file-based cache system for storing and retrieving data efficiently. Caching is useful for storing expensive data like API responses or computed results.

import 'package:nylo_framework/nylo_framework.dart';

// Cache a value for 60 seconds
String? value = await cache().saveRemember("my_key", 60, () {
  return "Hello World";
});

// Retrieve the cached value
String? cached = await cache().get("my_key");

// Remove from cache
await cache().clear("my_key");

Save with Expiration

Use saveRemember to cache a value with an expiration time:

String key = "user_profile";
int seconds = 300; // 5 minutes

Map<String, dynamic>? profile = await cache().saveRemember(key, seconds, () async {
  // This callback only runs on cache miss
  printInfo("Fetching from API...");
  return await api<UserApiService>((request) => request.getProfile());
});

On subsequent calls within the expiration window, the cached value is returned without executing the callback.

Save Forever

Use saveForever to cache data indefinitely:

String key = "app_config";

Map<String, dynamic>? config = await cache().saveForever(key, () async {
  return await api<ConfigApiService>((request) => request.getConfig());
});

The data remains cached until explicitly removed or the app's cache is cleared.

Retrieve Data

Get a cached value directly:

// Retrieve cached value
String? value = await cache().get<String>("my_key");

// With type casting
Map<String, dynamic>? data = await cache().get<Map<String, dynamic>>("user_data");

// Returns null if not found or expired
if (value == null) {
  print("Cache miss or expired");
}

If the cached item has expired, get() automatically removes it and returns null.

Store Data Directly

Use put to store a value directly without a callback:

// Store with expiration
await cache().put("session_token", "abc123", seconds: 3600);

// Store forever (no seconds parameter)
await cache().put("device_id", "xyz789");

Remove Data

// Remove a single item
await cache().clear("my_key");

// Remove all cached items
await cache().flush();

Check Cache

// Check if a key exists
bool exists = await cache().has("my_key");

// Get all cached keys
List<String> keys = await cache().documents();

// Get total cache size in bytes
int sizeInBytes = await cache().size();
print("Cache size: ${sizeInBytes / 1024} KB");

Caching API Responses

Using the api() Helper

Cache API responses directly:

Map<String, dynamic>? response = await api<ApiService>(
  (request) => request.get("https://api.github.com/repos/nylo-core/nylo"),
  cacheDuration: const Duration(minutes: 5),
  cacheKey: "github_repo_info",
);

printInfo(response);

Using NyApiService

Define caching in your API service methods:

class ApiService extends NyApiService {

  Future<Map<String, dynamic>?> getRepoInfo() async {
    return await network(
      request: (request) => request.get("https://api.github.com/repos/nylo-core/nylo"),
      cacheKey: "github_repo_info",
      cacheDuration: const Duration(hours: 1),
    );
  }

  Future<List<User>?> getUsers() async {
    return await network<List<User>>(
      request: (request) => request.get("/users"),
      cacheKey: "users_list",
      cacheDuration: const Duration(minutes: 10),
    );
  }
}

Then call the method:

Map<String, dynamic>? repoInfo = await api<ApiService>(
  (request) => request.getRepoInfo()
);

Platform Support

Nylo Website's cache uses file-based storage and has the following platform support:

On web platform, the cache gracefully degrades - callbacks are always executed and caching is bypassed.

// Check if cache is available
if (cache().isAvailable) {
  // Use caching
} else {
  // Web platform - cache not available
}

API Reference

Methods

Properties