add claude

Author: icebob

CLAUDE.md

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+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Development Commands
+
+- `npm test` - Run Jest tests with coverage
+- `npm run ci` - Run tests in watch mode for development
+- `npm run lint` - Run ESLint on src and test directories
+- `npm run lint:fix` - Auto-fix ESLint issues
+- `npm run dev` - Run development server with examples/index.js (simple example)
+- `npm run dev full` - Run development server with examples/full/index.js (full example)
+- `npm run deps` - Update dependencies interactively using ncu
+- `npm run postdeps` - Automatically run tests after dependency updates
+
+## Project Architecture
+
+This is a **Moleculer mixin** that integrates Apollo GraphQL Server 5 with Moleculer API Gateway. The core architecture consists of:
+
+### Core Components
+- **src/service.js** - Main service mixin factory that returns a Moleculer service schema
+- **src/ApolloServer.js** - Custom ApolloServer class extending @apollo/server
+- **src/gql.js** - GraphQL template literal formatter utility
+- **index.js** - Main module exports
+
+### Key Architectural Patterns
+
+**Service Mixin Pattern**: The library exports a factory function `ApolloService(options)` that returns a Moleculer service schema to be mixed into API Gateway services.
+
+**Auto-Schema Generation**: GraphQL schemas are dynamically generated from:
+- Service action definitions with `graphql` property containing `query`, `mutation`, or `subscription` fields
+- Service-level GraphQL definitions in `settings.graphql` 
+- Global typeDefs and resolvers passed to the mixin
+
+**Action-to-Resolver Mapping**: Moleculer actions automatically become GraphQL resolvers when they include GraphQL definitions. The system creates resolver functions that call `ctx.call(actionName, params)`.
+
+**DataLoader Integration**: Built-in DataLoader support for batch loading with automatic key mapping and caching via resolver configuration.
+
+**WebSocket Subscriptions**: GraphQL subscriptions are handled through WebSocket connections with PubSub pattern integration.
+
+### Testing Structure
+- **test/unit/** - Unit tests for individual components
+- **test/integration/** - Integration tests with full service setup
+- Jest snapshots for schema generation testing
+
+### Examples Structure
+- **examples/simple/** - Basic setup demonstration
+- **examples/full/** - Complete setup with multiple services, DataLoader, and complex resolvers
+
+## Important Development Notes
+
+**Schema Regeneration**: The GraphQL schema is automatically regenerated when services change (`$services.changed` event) unless `autoUpdateSchema: false`.
+
+**TypeScript Support**: Full TypeScript definitions in index.d.ts with comprehensive interfaces for all configuration options.
+
+**Node.js Version**: Requires Node.js >= 20.x.x (specified in package.json engines).