API Key Server

A simple HTTP server implemented in Rust that manages API keys associated with hex strings.

Features

• Generate API Keys: Create new API keys associated with hex strings
• Retrieve API Keys: Look up API keys by their associated hex string
• Rotate API Keys: Replace existing API keys with newly generated ones
• SQLite Storage: Persistent storage of hex string to API key mappings

API Endpoints

Endpoint	Method	Description
/gen-api-key	POST	Generate a new API key for a given hex string
/get-api-key	GET	Retrieve the API key associated with a hex string
/rotate-api-key	POST	Generate a new API key and replace the existing one

Note: The endpoints are named /gen-api-key but the actual handler function is called create_api_key to avoid Rust keyword conflicts.

Request & Response Formats

Generate API Key

Request:

{
  "hex_string": "0xabcdef123456"
}

Response:

{
  "api_key": "sk_...................=="
}

Get API Key

Request:

{
  "hex_string": "0xabcdef123456"
}

Response:

{
  "api_key": "sk_.................=="
}

Rotate API Key

Request:

{
  "hex_string": "0xabcdef123456"
}

Response:

{
  "api_key": "sk_................=="
}

Input Validation

The server validates that all hex strings:

• Start with the "0x" prefix
• Contain only valid hexadecimal characters (0-9, a-f, A-F) after the prefix

Installation and Running

1. Make sure you have Rust and Cargo installed.
2. Clone this repository.
3. Build the project:

cargo build --release

4. Run the server:

./target/release/apikey_server

The server will start on 127.0.0.1:8081 by default.

CORS Support

The server is configured with CORS (Cross-Origin Resource Sharing) support:

• Allows requests from any origin
• Supports all HTTP methods
• Allows all headers
• Sets a max age of 3600 seconds

This means web applications can interact with the API server even when hosted on different domains/ports.

Error Handling

The server returns appropriate HTTP status codes and error messages:

• 400 Bad Request: Invalid input (e.g., non-hex string, missing 0x prefix)
• 404 Not Found: Hex string not found in database
• 500 Internal Server Error: Database or other server errors

All errors are logged with appropriate severity levels and include detailed information to help with debugging.

Logging

The server implements comprehensive logging for better debugging and monitoring:

• Log Format: [TIMESTAMP] [LEVEL] - MESSAGE
• Access Logs: Every HTTP request is logged with client IP, request details, status code, and timing
• Validation Logs: Input validation results are logged at DEBUG/WARN level
• Database Logs: Database operations success/failure are logged
• Error Logs: Detailed error information is logged at appropriate levels

To see more detailed logs, you can set the RUST_LOG environment variable:

# Show all logs (including debug)
RUST_LOG=debug ./target/release/apikey_server

# Show only info and above (default)
RUST_LOG=info ./target/release/apikey_server

# Show only warnings and errors
RUST_LOG=warn ./target/release/apikey_server

Example log output:

[2025-04-23 14:32:15] [INFO] - Starting API Key Server
[2025-04-23 14:32:15] [INFO] - Initializing database connection to apikeys.db
[2025-04-23 14:32:15] [INFO] - Database connection established successfully
[2025-04-23 14:32:15] [INFO] - Database schema initialized successfully
[2025-04-23 14:32:15] [INFO] - Starting HTTP server on 127.0.0.1:8081
[2025-04-23 14:32:15] [INFO] - Configuring application with routes and middleware
[2025-04-23 14:32:27] [INFO] - Received request to create API key for hex string: 0x123abc
[2025-04-23 14:32:27] [DEBUG] - Hex string validation passed for: 0x123abc
[2025-04-23 14:32:27] [DEBUG] - Generated new API key for hex string: 0x123abc
[2025-04-23 14:32:27] [DEBUG] - Successfully stored API key in database for: 0x123abc
[2025-04-23 14:32:27] [INFO] - Successfully created API key for hex string: 0x123abc
[2025-04-23 14:32:15] [INFO] - Configuring application with routes and middleware
[2025-04-23 14:32:27] [INFO] - Received request to create API key for hex string: 0x123abc
[2025-04-23 14:32:27] [DEBUG] - Hex string validation passed for: 0x123abc
[2025-04-23 14:32:27] [DEBUG] - Generated new API key for hex string: 0x123abc
[2025-04-23 14:32:27] [DEBUG] - Successfully stored API key in database for: 0x123abc
[2025-04-23 14:32:27] [INFO] - Successfully created API key for hex string: 0x123abc

Implementation Details

• API keys are generated with a sk_ prefix followed by URL-safe Base64 encoded random bytes
• SQLite database is used for persistent storage in a file named apikeys.db
• The server uses the Actix Web framework for handling HTTP requests
• Comprehensive error handling with descriptive error messages
• Thread-safe access to the database using Mutex