fireproof_closet

Description:

fireproof closet

Fireproof Closet #
Cache your Firebase Storage data to the Fireproof Closet. When you use the FireproofImage
image provider, your image will be loaded instantly from the cache, or it will be downloaded and cached for future display.
Persistence #
The Fireproof Closet cache is persistent, so users can close and re-open the app
and not have to wait for images to download again.
In-Memory Speed #
Images displayed with the FireproofImage() provider are kept in the hot memory ImageCache for instant loading.
How it Works #
Fireproof Closet is a combination of a custom ImageProvider called FireproofImage which
is capable of acquiring and caching images from Firebase Storage, and the Hive
database to store and manage the data in persistence. Images are loaded into the hot memory ImageCache when displayed with
the FireproofImage() provider, or ahead of time with pre-caching by using FireproofCloset.downloadAndCache(context, storageRef);.
Cross Platform #

Hive is a cross-platform database that has fast speeds on all Flutter platforms.
The rest of the Fireproof Closet system is written in Dart which is inherently cross-platform

Speed Example #
Loading images from persistent cache vs downloading from Firebase Storage on iOS.
First cache read after the database is initialized may be slower. Cache reads below are for subsequent reads.
After reading from persistent cache, the image is stored in hot memory for instant loading. The following reflects speed improvements
compared to Firebase Storage downloading.
70 KB Image


Not found in cache, downloading from Firebase Storage

Cache stage duration: ~45ms
Firebase storage stage duration: 338ms



Loaded from cache

Cache stage duration: ~12ms
Firebase storage stage duration: 0ms



7 MB Image


Not found in cache, downloading from Firebase Storage

Cache stage duration: ~45ms
Firebase storage stage duration: 913ms



Loaded from cache

Cache stage duration: ~60ms
Firebase storage stage duration: 0ms



Future Changes #
In the future, Hive will be replaced with Isar which is a cross-platform database that uses
native code for each platform. However, Web does not currently work properly.

Isar loads large images into memory from persistent storage approximately 3x faster (7 MB in ~20ms) but the difference is negligible on smaller images under 1 MB.
This upgrade should be a non-breaking change since the API will remain identical, but with a higher speed database behind the scenes.

Implementation #
Initialize Fireproof Closet at app startup
import 'package:fireproof_closet/fireproof_closet.dart';

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

// Firebase: Initialize Firebase
await Firebase.initializeApp(
options: DefaultFirebaseOptions.currentPlatform,
);

// Initialize Firebase Storage Image Caching
await FireproofCloset.initialize();

// ...
}
copied to clipboard
Display An Image #
FireproofImage is an image provider that can be provided to an Image widget, or
any widget that takes an image provider.
import 'package:firebase_storage/firebase_storage.dart';
import 'package:fireproof_closet/fireproof_closet.dart';

class TestWidget extends StatelessWidget {
const TestWidget({Key? key}) : super(key: key);

@override
Widget build(BuildContext context) {
return Image(
image: FireproofImage(
storageRef: FirebaseStorage.instance
.ref()
.child("full/path/to/image.jpg"), // Required, the full relative path to the image in Firebase Storage
breakCache: true, // Optional, defaults to false, will force a fresh download and evict the image from memory
cacheDuration: const Duration(minutes: 5), // Optional, defaults to 365 days
cache: false, // Optional, defaults to true. If false, will not save the image to persistent cache
),
);
}
}
copied to clipboard
Precache Images (or files) #
Download images before they need to be shown to improve the user experience.
(This also works with any file, and not just images.)
This is helpful for long scrolling ListView.builder() type widgets, where you do not
want to wait for each image to download from Firebase Storage as it is scrolled into view. Load
it from the cache in milliseconds instead.
Optionally, await these downloads.
FireproofCloset.downloadAndCache(FirebaseStorage.instance.ref().child("full/path/to/image.jpg"));
copied to clipboard
Precache a ton of images at a time
// A list of Firebase Storage References
List<Reference> files = [
FirebaseStorage.instance.ref().child("full/path/to/image.jpg"),
FirebaseStorage.instance.ref().child("full/path/to/image1.jpg"),
FirebaseStorage.instance.ref().child("full/path/to/image2.jpg"),
];

// Cache them all at once in a loop
// If context is null, images will only be downloaded to persistence and not loaded into hot memory [ImageCache]
for (var file in files) {
FireproofCloset.downloadAndCache(storageRef, context: context);
}
copied to clipboard

Helpful Utilities #
Clear the cache
Delete all items from the cache
FireproofCloset.clearCache();
copied to clipboard

Print Cache Status
FireproofCloset.cacheStatus();
copied to clipboard
Example Output
flutter: Number of cached items: 1
flutter: Total cache size 0.0689 MB
copied to clipboard

Print Cache Items
FireproofCloset.printCacheItems();
copied to clipboard
Example Output
flutter: =====================
flutter: All cached items:
flutter: 0 CachedData: fullPath: full/path/to/image.jpg, size: 68.87 kb, created: 2022-11-20 20:19:04.624, expires: 2022-11-20 20:24:04.624
flutter: End of cached items.
flutter: =====================
copied to clipboard