# REST API Server

REST API implementation for the ChainID 138 Explorer Platform.

## Structure

- `server.go` - Main server setup and route configuration
- `routes.go` - Route handlers and URL parsing
- `blocks.go` - Block-related endpoints
- `transactions.go` - Transaction-related endpoints
- `addresses.go` - Address-related endpoints
- `search.go` - Unified search endpoint
- `validation.go` - Input validation utilities
- `middleware.go` - HTTP middleware (logging, compression)
- `errors.go` - Error response utilities

## API Endpoints

### Blocks
- `GET /api/v1/blocks` - List blocks (paginated)
- `GET /api/v1/blocks/{chain_id}/{number}` - Get block by number
- `GET /api/v1/blocks/{chain_id}/hash/{hash}` - Get block by hash

### Transactions
- `GET /api/v1/transactions` - List transactions (paginated, filterable)
- `GET /api/v1/transactions/{chain_id}/{hash}` - Get transaction by hash

### Addresses
- `GET /api/v1/addresses/{chain_id}/{address}` - Get address information

### Search
- `GET /api/v1/search?q={query}` - Unified search (auto-detects type: block number, address, or transaction hash)

### Health
- `GET /health` - Health check endpoint

## Features

- Input validation (addresses, hashes, block numbers)
- Pagination support
- Query timeouts for database operations
- CORS headers
- Request logging
- Error handling with consistent error format
- Health checks with database connectivity

## Running

```bash
cd backend/api/rest
go run main.go
```

Or use the development script:
```bash
./scripts/run-dev.sh
```

## Configuration

Set environment variables:
- `DB_HOST` - Database host
- `DB_PORT` - Database port
- `DB_USER` - Database user
- `DB_PASSWORD` - Database password
- `DB_NAME` - Database name
- `PORT` - API server port (default: 8080)
- `CHAIN_ID` - Chain ID (default: 138)