Api Security Hardening

# API Security Hardening

## Table of Contents

- [Overview](#overview)
- [When to Use](#when-to-use)
- [Quick Start](#quick-start)
- [Reference Guides](#reference-guides)
- [Best Practices](#best-practices)

## Overview

Implement comprehensive API security measures including authentication, authorization, rate limiting, input validation, and attack prevention to protect against common vulnerabilities.

## When to Use

- New API development
- Security audit remediation
- Production API hardening
- Compliance requirements
- High-traffic API protection
- Public API exposure

## Quick Start

Minimal working example:

```javascript
// secure-api.js - Comprehensive API security
const express = require("express");
const helmet = require("helmet");
const rateLimit = require("express-rate-limit");
const mongoSanitize = require("express-mongo-sanitize");
const xss = require("xss-clean");
const hpp = require("hpp");
const cors = require("cors");
const jwt = require("jsonwebtoken");
const validator = require("validator");

class SecureAPIServer {
  constructor() {
    this.app = express();
    this.setupSecurityMiddleware();
    this.setupRoutes();
  }

  setupSecurityMiddleware() {
    // 1. Helmet - Set security headers
    this.app.use(
      helmet({
        contentSecurityPolicy: {
          directives: {
            defaultSrc: ["'self'"],
// ... (see reference guides for full implementation)
```

## Reference Guides

Detailed implementations in the `references/` directory:

| Guide | Contents |
|---|---|
| [Node.js/Express API Security](references/nodejsexpress-api-security.md) | Node.js/Express API Security |
| [Python FastAPI Security](references/python-fastapi-security.md) | Python FastAPI Security |
| [API Gateway Security Configuration](references/api-gateway-security-configuration.md) | API Gateway Security Configuration |

## Best Practices

### ✅ DO

- Use HTTPS everywhere
- Implement rate limiting
- Validate all inputs
- Use security headers
- Log security events
- Implement CORS properly
- Use strong authentication
- Version your APIs

### ❌ DON'T

- Expose stack traces
- Return detailed errors
- Trust user input
- Use HTTP for APIs
- Skip input validation
- Ignore rate limiting


#!/bin/bash
# security-checklist.sh - Generate a security review checklist
# Usage: ./security-checklist.sh [--output checklist.md]

set -euo pipefail

OUTPUT="${{1:-/dev/stdout}}"

cat > "$OUTPUT" << 'CHECKLIST'
# Security Review Checklist

## Authentication & Authorization
- [ ] All endpoints require authentication
- [ ] Role-based access control implemented
- [ ] Session management is secure

## Input Validation
- [ ] All user inputs are validated
- [ ] SQL injection prevention
- [ ] XSS prevention

## Data Protection
- [ ] Sensitive data encrypted at rest
- [ ] Sensitive data encrypted in transit
- [ ] PII handling compliant

## TODO: Add domain-specific security checks
CHECKLIST

echo "Checklist generated: $OUTPUT" >&2


# API Gateway Security Configuration

## API Gateway Security Configuration

```yaml
# nginx-api-gateway.conf
# Nginx API Gateway with security hardening

http {
    # Security headers
    add_header X-Frame-Options "DENY" always;
    add_header X-Content-Type-Options "nosniff" always;
    add_header X-XSS-Protection "1; mode=block" always;
    add_header Strict-Transport-Security "max-age=31536000; includeSubDomains" always;
    add_header Content-Security-Policy "default-src 'self'" always;

    # Rate limiting zones
    limit_req_zone $binary_remote_addr zone=api_limit:10m rate=10r/s;
    limit_req_zone $binary_remote_addr zone=auth_limit:10m rate=1r/s;
    limit_conn_zone $binary_remote_addr zone=conn_limit:10m;

    # Request body size limit
    client_max_body_size 10M;
    client_body_buff