prism/CLAUDE.md

CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

Project Overview

Prism is a real-time messenger built with Expo (React Native) frontend and NestJS backend using GraphQL and PostgreSQL. The project is structured as a monorepo with separate frontend and backend directories.

Development Commands

Backend (NestJS)

cd backend
npm run start:dev    # Development server with hot reload
npm run build        # Build for production
npm run test         # Run unit tests
npm run test:e2e     # Run end-to-end tests
npm run lint         # ESLint with auto-fix
npm run format       # Prettier formatting

Frontend (Expo/React Native)

cd frontend
npx expo start       # Start Expo development server
npx expo start --ios # Start with iOS simulator
npx expo start --android # Start with Android emulator

Architecture

Backend Architecture

• Framework: NestJS with TypeScript
• API: GraphQL using code-first approach with auto-generated schema
• Database: PostgreSQL with TypeORM (synchronize enabled in development)
• Authentication: JWT with Passport strategy
• Real-time: GraphQL Subscriptions for live updates
• Module Structure:
  • auth/ - JWT authentication and guards
  • users/ - User management and profiles
  • conversations/ - Chat/conversation management
  • messages/ - Message handling and real-time updates

Frontend Architecture

• Framework: Expo with React Native and TypeScript
• State Management: Apollo Client for GraphQL state management
• UI Framework: React Native Paper with custom theming
• Navigation: React Navigation with stack and tab navigators
• Storage: AsyncStorage for token persistence
• Key Contexts: AuthContext for authentication state

Data Flow

• Frontend communicates with backend exclusively through GraphQL
• Real-time updates via GraphQL subscriptions
• JWT tokens stored in AsyncStorage and included in GraphQL requests via authLink
• Apollo Client handles caching with cache-and-network fetch policy

Database Configuration

The project supports both remote and local PostgreSQL:

• Remote database is the default (configured in backend .env)
• Local database can be enabled by uncommenting postgres service in docker-compose.yml
• TypeORM synchronize is enabled in development (automatic schema updates)

Environment Configuration

Backend Environment Variables

Required in backend/.env:

DATABASE_HOST=
DATABASE_PORT=5432
DATABASE_USERNAME=
DATABASE_PASSWORD=
DATABASE_NAME=prism_messenger
JWT_SECRET=
JWT_EXPIRATION=7d

Frontend API Configuration

Update frontend/src/config/api.ts based on development environment:

• iOS simulator: http://localhost:3000/graphql
• Android emulator: http://10.0.2.2:3000/graphql
• Physical device: http://YOUR_IP:3000/graphql

Key Implementation Details

• GraphQL schema is auto-generated at backend/src/schema.gql
• All GraphQL queries, mutations, and subscriptions are centralized in frontend/src/graphql/
• Authentication uses JWT with bearer token authorization
• Real-time features implemented via GraphQL subscriptions with graphql-ws
• Frontend theme system supports both light and dark modes
• Message features include send, edit, delete with real-time updates