flutter_shared_storage

A federated Flutter package suite for storing files and folders in the cloud, with a Firebase backend.

Packages

Package	Purpose
cloud_storage_platform_interface	Backend-agnostic contract: CloudStorage, CloudNode, UploadTask, etc. Depend on this if you're writing a new backend.
cloud_storage_firebase	Firebase Storage + Firestore implementation of the interface.
cloud_storage	Umbrella package. Re-exports the interface and the default Firebase implementation. Depend on this from app code.
cloud_storage_gallery	Optional photo/video viewer + folder grid widgets.

Plus:

• example/ — demo Flutter app exercising upload, browse, and the gallery viewer.

Architecture at a glance

+----------------+     +---------------------------+
|   your app     | --> | cloud_storage (umbrella)  |
+----------------+     +-------------+-------------+
                                     |
                +--------------------+--------------------+
                |                                         |
   cloud_storage_platform_interface   <-- implements --   cloud_storage_firebase
                                                          (Firestore + Storage)

Design choices

• Federated plugin pattern. New backends (S3, Supabase, ...) implement CloudStorage and ship as a separate package.
• Firestore for metadata, Storage for bytes. Listings and folder hierarchy live in Firestore for fast, real-time reads.
• Caller-supplied paths. The package makes no assumption about where data lives — you pass firestorePath and storagePath to FirebaseCloudStorage(...). Auth, tenancy, and access control are entirely your concern.
• No sharing logic. Access control is the consumer's responsibility (security rules + custom claims).
• Headless core, optional UI. Gallery widgets are a separate package; the core API is repository-style with streams.
• Client-side thumbnails. The caller generates thumbnail + preview JPEGs and passes them to upload() alongside the original — the package writes them to the well-known variant paths. No Cloud Functions, no Blaze plan required.
• Auto-rename on conflict. Same-name uploads/folders get a (1), (2), ... suffix.
• Theme- and locale-aware widgets. The gallery package has no inline colors and respects Directionality.of(context) for RTL/LTR.

Getting started

dart pub global activate melos
melos bootstrap
melos run analyze

Platforms

First release targets Android and iOS. Web/desktop can be added by the Firebase implementation since firebase_storage and cloud_firestore already support them — the gallery package's video viewer is the main blocker.