Firebase Platform

---
name: firebase-platform
description: Firebase services, platform guides, and tips for integration with Angular projects.
version: 1.0.0
tags: [firebase, platform]
---

# SKILL: Firebase Platform Master Guide

Consolidated reference for AngularFire SDK and Firebase Data Connect (GQL + PostgreSQL).

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## 🔥 1. AngularFire Core (SDK)

### Real-time Database & Firestore

- **Reactive Pattern**: Use `collectionData`, `docData` and convert to signals using `toSignal()`.
- **Dependency Injection**: Use `inject(Firestore)`, `inject(Auth)`, etc.
- **Security**: Security rules are the primary defense. Never trust the client.

### Authentication

- **State management**: Track `user` status in an `AuthStore`.
- **Guards**: Use functional `canActivate` guards with `Auth` service.

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## ⚡ 2. Firebase Data Connect (GQL + PostgreSQL)

### Schema Workflow

- **Schema First**: Define `@table` in `schema.gql`.
- **Generation**: Run `firebase dataconnect:sdk:generate` after schema changes.
- **Strict Types**: Use the generated SDK; never edit `dataconnect-generated/`.

### Directive Rules

- `@table`: Required for all database entities.
- `@auth`: Required for all types (No public access allowed).
- `@default`: Use for UUIDs (`uuidV4()`) and timestamps (`request.time`).
- `@col(name: "...")`: Map JSON keys to DB columns if different.

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## 🏗️ 3. Integration with NgRx Signals

- **Query Wrapping**:
  ```typescript
  export const MyStore = signalStore(
    withMethods((store, dc = inject(DataConnectService)) => ({
      loadData: rxMethod<void>(
        pipe(
          switchMap(() => dc.myDataQuery()),
          tapResponse({
            next: (res) => patchState(store, { data: res.data }),
            error: console.error,
          }),
        ),
      ),
    })),
  );
  ```

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## 🔒 4. Security & Performance

- **Secrets**: Store Firebase API keys and config in `environment.ts`.
- **Query Design**: Fetch only required fields in GraphQL.
- **Auth Pattern**: `@auth(rules: [{ allow: OWNER, ownerField: "userId" }])`.
- **No Hardcoded Secrets**: Secrets must stay in environment variables or GCP Secret Manager.

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> **Law**: After any schema change, the SDK MUST be regenerated before editing application logic.