Module messaging 

Firebase Messaging Port (Rust)

Introduction

Rust implementation of the Firebase Cloud Messaging (FCM) web SDK surface. The goal is to mirror the @firebase/messaging APIs so applications can manage web push permissions, registration tokens and foreground/background notifications from Rust (including WASM builds).

Porting status

• messaging 25% [### ]

Quick Start Example

use firebase_rs_sdk::messaging::{
    self, PermissionState, PushSubscriptionManager, ServiceWorkerManager,
};

#[cfg(all(target_arch = "wasm32", feature = "wasm-web"))]
async fn initialise_messaging() -> messaging::error::MessagingResult<()> {
    if !messaging::is_supported() {
        return Err(messaging::error::unsupported_browser(
            "Browser is missing push APIs",
        ));
    }

    let mut sw_manager = ServiceWorkerManager::new();
    let registration = sw_manager.register_default().await?;

    let mut push_manager = PushSubscriptionManager::new();
    let vapid_key = "<your-public-vapid-key>";

    let messaging = messaging::get_messaging(None)?;
    if matches!(messaging.request_permission().await?, PermissionState::Granted) {
        let subscription = push_manager.subscribe(&registration, vapid_key).await?;
        let details = subscription.details()?;
        let _token = messaging.get_token(Some(vapid_key)).await?;
    }
    Ok(())
}

Implemented

• Component registration that exposes Messaging through the shared component system.
• In-memory token management for get_token and delete_token with validation of VAPID keys.
• messaging::is_supported() guard that mirrors packages/messaging/src/api/isSupported.ts for web builds.
• Asynchronous Messaging::request_permission flow that awaits Notification.requestPermission and surfaces messaging/permission-blocked and messaging/unsupported-browser errors.
• ServiceWorkerManager helper that registers the default Firebase messaging worker (mirrors helpers/registerDefaultSw.ts) and caches the resulting registration for reuse.
• WASM-only PushSubscriptionManager that wraps PushManager.subscribe, returns subscription details and supports unsubscribe/error mapping aligned with the JS SDK implementation.
• Token persistence layer that stores token metadata (including subscription details and creation time) per app, mirroring the IndexedDB-backed token manager with IndexedDB on wasm (plus BroadcastChannel sync) and in-memory fallback on native targets. Weekly refresh logic invalidates tokens after 7 days to trigger regeneration.
• Minimal error types for invalid arguments, internal failures and token deletion.
• Non-WASM unit test coverage for permission/token flows, invalid arguments, token deletion, service worker and push subscription stubs.

Still to do

• Track permission changes across sessions and expose notification status helpers similar to the JS SDK.
• Call the Installations and FCM REST endpoints to create, refresh and delete tokens, including weekly refresh checks.
• Coordinate multi-tab state and periodic refresh triggers using IndexedDB change listeners (BroadcastChannel / storage events).
• Foreground/background message listeners, payload decoding and background handlers.
• Environment-specific guards (SW vs window scope), emulator/testing helpers and extended error coverage.

Next steps - Detailed completion plan

1. Adopt the async Installations refresh path documented in src/installations/README.md (wasm fetch client + shared persistence) so messaging can obtain real FIS tokens on every target.
2. Implement the Installations/FCM REST interactions for token create/update/delete, mirroring internals/token-manager.ts.
3. Add multi-tab coordination (BroadcastChannel/localStorage) so IndexedDB state stays in sync across contexts.
4. Port message delivery APIs (onMessage, onBackgroundMessage) and event dispatchers, including WASM gating for background handlers.
5. Expand the error catalog to match packages/messaging/src/util/errors.ts, update documentation and backfill tests for the newly added behaviours.

Modules

error

Structs

Messaging

PushSubscriptionManager

ServiceWorkerManager

ServiceWorkerRegistrationHandle

Enums

PermissionState

Notification permission states as exposed by the Web Notifications API.

Functions

get_messaging

is_supported

Returns false outside a web environment, where the required browser APIs are unavailable.

register_messaging_component