Authentication Setup Documentation — Complete Guide

Authentication setup documentation guides developers through configuring API keys, OAuth 2.0, JWT, and other authentication methods. Learn how to document auth flows clearly with step-by-step instructions and examples.

What You'll Learn

You will learn how to document authentication methods for your API, including API keys, OAuth 2.0, and JWT, with clear instructions and working examples.

Why It Matters

Authentication is the most common integration hurdle. If developers cannot authenticate successfully, they cannot use any other feature. Clear authentication documentation reduces support tickets and accelerates integration.

Real-World Use

Durga Antivirus Pro offers API key authentication for simple use cases and OAuth 2.0 for enterprise integrations. The authentication guide includes step-by-step setup, code examples, and troubleshooting.

flowchart TD
  A[Authentication Methods] --> B[API Keys]
  A --> C[OAuth 2.0]
  A --> D[JWT]
  B --> E[Simple and fast]
  B --> F[Good for personal use]
  C --> G[Enterprise-grade]
  C --> H[Supports scopes]
  D --> I[Stateless]
  D --> J[Custom implementation]
  A:::current
  classDef current fill:#f90,color:#fff,stroke:#333,stroke-width:2px

API Key Authentication Guide

# API Key Authentication

API keys are the simplest way to authenticate. Each request includes your
API key in the Authorization header.

## Getting an API Key

1. Log in to the [Developer Dashboard](https://developer.example.com)
2. Navigate to API Keys
3. Click "Create API Key"
4. Give your key a name (e.g., "Production")
5. Select the permissions (scopes) for this key
6. Click "Create" and **copy the key immediately** — it won't be shown again

## Using Your API Key

Include the API key in every request:

```bash
curl -X GET "https://api.example.com/v1/threats" \
  -H "Authorization: Bearer dga_your_api_key_here"

import requests

response = requests.get(
    "https://api.example.com/v1/threats",
    headers={"Authorization": "Bearer dga_your_api_key_here"}
)

API Key Best Practices

• Rotate keys every 90 days
• Use different keys for development and production
• Never commit API keys to version control
• Revoke keys immediately if compromised
• Set appropriate scope limits on each key

## OAuth 2.0 Authentication Guide

```markdown
# OAuth 2.0 Authentication

OAuth 2.0 is recommended for enterprise integrations that require
fine-grained permissions and user delegation.

## Authorization Code Flow

1. Register your application to get a client ID and secret
2. Redirect the user to the authorization URL
3. Handle the callback with the authorization code
4. Exchange the code for an access token
5. Use the access token for API requests

## Step 1: Register Your Application

```bash
curl -X POST "https://api.example.com/v1/apps" \
  -H "Authorization: Bearer dga_admin_key" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "My Integration",
    "redirect_uris": ["https://myapp.com/callback"],
    "scopes": ["threats:read", "threats:write"]
  }'

Step 2: Get the Authorization URL

authorization_url = (
    "https://api.example.com/oauth/authorize"
    "?response_type=code"
    "&client_id=YOUR_CLIENT_ID"
    "&redirect_uri=https://myapp.com/callback"
    "&scope=threats:read"
    "&state=random_state_string"
)

## JWT Authentication

```python
import jwt
import time

# Create a JWT token
payload = {
    "sub": "user_123",
    "iat": int(time.time()),
    "exp": int(time.time()) + 3600,
    "scopes": ["threats:read"]
}

secret = "your_client_secret"
token = jwt.encode(payload, secret, algorithm="HS256")
print(f"JWT: {token}")

Common Mistakes

1. Writing Authentication Docs Before the Auth Flow Is Finalized

Authentication documentation written before the flow is finalized becomes outdated immediately. Document after implementation.

2. No Visual Diagram of the Auth Flow

OAuth 2.0 has multiple steps. A sequence diagram helps developers understand the flow at a glance.

3. Incomplete Error Handling

Document what happens when tokens expire, keys are invalid, or scopes are insufficient. Include error codes and resolution steps.

4. Not Covering Token Refresh

For OAuth and JWT, developers need to know how to refresh expired tokens. Document the refresh flow.

5. No Security Best Practices

Tell developers how to securely store keys, rotate tokens, and handle compromised credentials.

Practice Questions

1. What are three common API authentication methods?

API keys, OAuth 2.0, and JWT (JSON Web Tokens).

2. Why should API keys not be committed to version control?

Committed keys are exposed to anyone with Repository access. Keys can be compromised through leaked repositories.

3. What is the purpose of scopes in API authentication?

Scopes limit what an API key or token can do, providing fine-grained access control.

4. How often should API keys be rotated?

Every 90 days is a common policy. Rotate immediately if a key is compromised.

5. Challenge: Write an authentication guide for an API that supports both API key and OAuth 2.0 authentication. Include step-by-step setup, code examples in curl and Python, a sequence diagram of the OAuth flow, and troubleshooting for common auth errors.

FAQ

Mini Project

Create an authentication setup guide for an API that supports both API key and OAuth 2.0. Include step-by-step instructions with screenshots, code examples in curl and Python, a Mermaid sequence diagram of the OAuth flow, error troubleshooting, and security best practices.

What's Next

With authentication documented, learn how to write Tutorials and Examples that guide developers through common integration scenarios.