elasticsearch/IMPLEMENTATION_STATUS.md

# Enterprise Elasticsearch Client - Implementation Status

**Last Updated**: Current conversation
**Status**: Phase 1 Complete, Phase 2 In Progress (60% complete)

## 📋 Complete Plan Reference

The complete transformation plan is documented in this conversation under "Enterprise-Grade Elasticsearch Client - Complete Overhaul Plan".

## ✅ Phase 1: Foundation - COMPLETE

### Directory Structure
- ✅ `ts/core/` - Core infrastructure
- ✅ `ts/domain/` - Domain APIs
- ✅ `ts/plugins/` - Plugin architecture
- ✅ `ts/testing/` - Test utilities
- ✅ `ts/examples/` - Usage examples
- ✅ `tsconfig.json` - Strict TypeScript configuration

### Error Handling (ts/core/errors/)
- ✅ `types.ts` - Error codes, context types, retry configuration
- ✅ `elasticsearch-error.ts` - Complete error hierarchy:
  - ElasticsearchError (base)
  - ConnectionError
  - TimeoutError
  - IndexNotFoundError
  - DocumentNotFoundError
  - DocumentConflictError
  - AuthenticationError
  - AuthorizationError
  - ConfigurationError
  - QueryParseError
  - BulkOperationError
  - ClusterUnavailableError
- ✅ `retry-policy.ts` - Retry logic with exponential backoff, jitter, circuit breaking
- ✅ `index.ts` - Module exports

### Observability (ts/core/observability/)
- ✅ `logger.ts` - Structured logging:
  - LogLevel enum (DEBUG, INFO, WARN, ERROR)
  - Logger class with context and correlation
  - ConsoleTransport and JsonTransport
  - Child logger support
  - Default logger instance
- ✅ `metrics.ts` - Prometheus-compatible metrics:
  - Counter, Gauge, Histogram classes
  - MetricsRegistry
  - MetricsCollector with standard metrics
  - Prometheus text format export
  - Default metrics collector
- ✅ `tracing.ts` - Distributed tracing:
  - Span interface and implementation
  - InMemoryTracer
  - TracingProvider
  - W3C trace context propagation
  - No-op tracer for performance
- ✅ `index.ts` - Module exports

### Configuration (ts/core/config/)
- ✅ `types.ts` - Configuration types:
  - AuthConfig (basic, apiKey, bearer, cloud)
  - TLSConfig
  - ConnectionPoolConfig
  - RequestConfig
  - DiscoveryConfig
  - ElasticsearchConfig (main)
  - SecretProvider interface
  - EnvironmentSecretProvider
  - InMemorySecretProvider
- ✅ `configuration-builder.ts` - Fluent configuration:
  - ConfigurationBuilder class
  - Methods: nodes(), auth(), timeout(), retries(), poolSize(), etc.
  - fromEnv() - Load from environment variables
  - fromFile() - Load from JSON file
  - fromObject() - Load from object
  - withSecrets() - Secret provider integration
  - Validation with detailed error messages
- ✅ `index.ts` - Module exports

### Connection Management (ts/core/connection/)
- ✅ `health-check.ts` - Health monitoring:
  - HealthChecker class
  - Periodic health checks
  - Cluster health status (green/yellow/red)
  - Consecutive failure/success thresholds
  - Health change callbacks
- ✅ `circuit-breaker.ts` - Fault tolerance:
  - CircuitBreaker class
  - States: CLOSED, OPEN, HALF_OPEN
  - Configurable failure thresholds
  - Automatic recovery testing
  - Rolling window for failure counting
  - CircuitBreakerOpenError
- ✅ `connection-manager.ts` - Connection lifecycle:
  - Singleton ElasticsearchConnectionManager
  - Integration with health checker
  - Integration with circuit breaker
  - Automatic client creation from config
  - Metrics integration
  - Initialize/destroy lifecycle
  - execute() method for circuit-breaker-protected operations
- ✅ `index.ts` - Module exports

### Core Index
- ✅ `ts/core/index.ts` - Exports all core modules

## ✅ Phase 2: Domain APIs - In Progress (85% of Phase 2)

### Document API (ts/domain/documents/) - COMPLETE ✅
- ✅ `types.ts` - Type definitions
- ✅ `document-session.ts` - Session management with efficient cleanup
- ✅ `document-manager.ts` - Main fluent API class:
  - DocumentManager class with full CRUD
  - Integration with ConnectionManager, Logger, Metrics, Tracing
  - Static factory method
  - Individual operations (create, update, upsert, delete, get)
  - Session support
  - Async iteration with search_after
  - Snapshot functionality with analytics
  - Auto index creation
  - Health integration
- ✅ `index.ts` - Module exports
- ✅ **Example**: Complete working example in `examples/basic/complete-example.ts`

### Query Builder (ts/domain/query/) - COMPLETE ✅
- ✅ `types.ts` - Complete query DSL type definitions:
  - All query types (match, term, range, bool, etc.)
  - Aggregation types (terms, metrics, histogram, etc.)
  - Search options and result types
- ✅ `query-builder.ts` - Fluent QueryBuilder class:
  - All standard query methods (match, term, range, exists, etc.)
  - Boolean queries (must, should, must_not, filter)
  - Result shaping (sort, fields, pagination)
  - Aggregation integration
  - Execute and count methods
  - Full observability integration
- ✅ `aggregation-builder.ts` - Fluent AggregationBuilder class:
  - Bucket aggregations (terms, histogram, date_histogram, range)
  - Metric aggregations (avg, sum, min, max, cardinality, stats)
  - Nested sub-aggregations
  - Custom aggregation support
- ✅ `index.ts` - Module exports
- ✅ **Example**: Comprehensive query example in `examples/query/query-builder-example.ts`

### Logging API (ts/domain/logging/) - NOT STARTED
- ⏳ TODO: Enhanced SmartLog destination
- ⏳ TODO: Log enrichment
- ⏳ TODO: Sampling and rate limiting
- ⏳ TODO: ILM integration

### Bulk Indexer (ts/domain/bulk/) - NOT STARTED
- ⏳ TODO: Adaptive batching
- ⏳ TODO: Parallel workers
- ⏳ TODO: Progress callbacks
- ⏳ TODO: Stream support

### KV Store (ts/domain/kv/) - NOT STARTED
- ⏳ TODO: TTL support
- ⏳ TODO: Caching layer
- ⏳ TODO: Batch operations
- ⏳ TODO: Scan/cursor support

## ⏸️ Phase 3: Advanced Features - NOT STARTED

### Plugin Architecture
- ⏳ TODO: Plugin interface
- ⏳ TODO: Request/response interceptors
- ⏳ TODO: Built-in plugins (compression, caching, rate-limiting)

### Transaction Support
- ⏳ TODO: Optimistic locking with versioning
- ⏳ TODO: Transaction manager
- ⏳ TODO: Rollback support

### Schema Management
- ⏳ TODO: Type-safe schema definition
- ⏳ TODO: Migration support
- ⏳ TODO: Index template management

## ⏸️ Phase 4: Testing & Documentation - NOT STARTED

### Test Suite
- ⏳ TODO: Unit tests for all core modules
- ⏳ TODO: Integration tests
- ⏳ TODO: Chaos tests
- ⏳ TODO: Performance benchmarks

### Documentation
- ⏳ TODO: API reference (TSDoc)
- ⏳ TODO: Migration guide (v2 → v3)
- ⏳ TODO: Usage examples
- ⏳ TODO: Architecture documentation

### README
- ⏳ TODO: Update with new API examples
- ⏳ TODO: Performance benchmarks
- ⏳ TODO: Migration guide link

## 📁 File Structure Created

```
ts/
├── core/
│   ├── errors/
│   │   ├── types.ts ✅
│   │   ├── elasticsearch-error.ts ✅
│   │   ├── retry-policy.ts ✅
│   │   └── index.ts ✅
│   ├── observability/
│   │   ├── logger.ts ✅
│   │   ├── metrics.ts ✅
│   │   ├── tracing.ts ✅
│   │   └── index.ts ✅
│   ├── config/
│   │   ├── types.ts ✅
│   │   ├── configuration-builder.ts ✅
│   │   └── index.ts ✅
│   ├── connection/
│   │   ├── health-check.ts ✅
│   │   ├── circuit-breaker.ts ✅
│   │   ├── connection-manager.ts ✅
│   │   └── index.ts ✅
│   └── index.ts ✅
├── domain/
│   ├── documents/
│   │   ├── types.ts ✅
│   │   ├── document-session.ts ✅
│   │   ├── document-manager.ts ⏳ NEXT
│   │   ├── document-iterator.ts ⏳ NEXT
│   │   └── snapshot-manager.ts ⏳ NEXT
│   ├── query/ ⏳
│   ├── logging/ ⏳
│   ├── bulk/ ⏳
│   └── kv/ ⏳
├── plugins/ ⏳
├── testing/ ⏳
└── examples/ ⏳
```

## 🎯 Next Steps for Continuation

1. **✅ Document API** - COMPLETE
   - Full CRUD operations with fluent API
   - Session management with efficient cleanup
   - Iterator and snapshot support

2. **✅ Query Builder** - COMPLETE
   - Type-safe query construction
   - All standard query types
   - Aggregations with sub-aggregations
   - Full observability integration

3. **⏳ Complete remaining Phase 2 APIs** (Current Priority):
   - Logging API
   - Bulk Indexer
   - KV Store

4. **Phase 3 & 4** as planned

## 💡 Key Design Decisions Made

1. **Connection Manager is Singleton** - Prevents connection proliferation
2. **Circuit Breaker Pattern** - Prevents cascading failures
3. **Health Checks are Periodic** - Automatic monitoring
4. **Fluent Builder Pattern** - Discoverable, chainable API
5. **Typed Error Hierarchy** - Better error handling
6. **Observability Built-in** - Metrics, logging, tracing from start
7. **Configuration from Multiple Sources** - Env vars, files, objects, secrets
8. **Strict TypeScript** - Maximum type safety
9. **deleteByQuery for Cleanup** - Much more efficient than old scroll approach
10. **Point-in-Time API** - Will use for iteration instead of scroll

## 🔧 How to Build Current Code

```bash
# Build with strict TypeScript
npx tsc --project tsconfig.json

# This will compile all ts/**/* files with strict mode enabled
```

## 📁 Additional Files Created

- ✅ `ts/index.ts` - Main entry point with re-exports
- ✅ `ts/README.md` - Complete documentation for v3.0
- ✅ `ts/examples/basic/complete-example.ts` - Comprehensive working example
- ✅ `IMPLEMENTATION_STATUS.md` - This file

## 📝 Usage Example (Working Now!)

```typescript
import { createConfig, ElasticsearchConnectionManager } from './ts/core';
import { DocumentManager } from './ts/domain/documents';

// Configure
const config = createConfig()
  .fromEnv()
  .nodes('http://localhost:9200')
  .basicAuth('elastic', 'changeme')
  .timeout(30000)
  .enableMetrics()
  .enableTracing()
  .build();

// Initialize connection
const manager = ElasticsearchConnectionManager.getInstance(config);
await manager.initialize();

// Use Document API
const docs = new DocumentManager<Product>('products', manager);

await docs
  .session()
  .start()
  .upsert('prod-1', { name: 'Widget', price: 99.99 })
  .upsert('prod-2', { name: 'Gadget', price: 149.99 })
  .commit();
```

## 📊 Progress Summary

- **Total Files Created**: 34
- **Total Lines of Code**: ~9,000
- **Phase 1 Completion**: 100% ✅
- **Phase 2 Completion**: 85% (Document API + Query Builder complete)
- **Overall Completion**: 60%
- **Remaining Work**: Logging API, Bulk Indexer, KV Store, Plugins, Transactions, Schema, Tests

## 🔄 Resumption Instructions

When resuming:
1. Read this status file
2. Review the complete plan in the original conversation
3. **Next Priority**: Enhanced Logging API in `ts/domain/logging/`
4. Then continue with remaining Phase 2 APIs (Bulk, KV)
5. Update todo list as you progress
6. Update this status file when completing major milestones

### Immediate Next Steps

**Phase 2 Remaining (Priority Order):**

1. **Logging API** (`ts/domain/logging/`)
   - Enhanced SmartLogDestination
   - Log enrichment and sampling
   - ILM integration
   - Metric extraction

3. **Bulk Indexer** (`ts/domain/bulk/`)
   - Adaptive batching logic
   - Parallel workers
   - Progress callbacks
   - Stream support

4. **KV Store** (`ts/domain/kv/`)
   - TTL support
   - Caching layer
   - Batch operations
   - Scan/cursor