Swagger Authorization - Simple Guide

Step-by-Step Process & Entities

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┌─────────────────────────────────────────────────────────────────┐
│          API TEST & VALIDATION FLOW (Steps 7-8)                 │
└─────────────────────────────────────────────────────────────────┘

    ┌────────────────────────────────┐
    │   Developer clicks "Try it out"│
    │   on an API endpoint           │
    └────────────┬───────────────────┘
                 │
                 │ Step 7: Swagger adds token to request
                 ▼
    ┌──────────────────────────────────┐
    │  HTTP Request                    │
    │  GET /api/v1/WorkOrder/Overview  │
    │  Authorization: Bearer eyJ...    │
    └──────┬───────────────────────────┘
           │
           │ Step 8: Request received
           ▼
    ┌──────────────────────────────────────┐
    │  ApiService/IntegrationServiceAPI    │
    │  JWT Authentication Middleware       │
    └──────┬───────────────────────────────┘
           │
           │ Token Validation:
           │ ✓ Issuer (Azure AD tenant)
           │ ✓ Audience (this API)
           │ ✓ Signature (Azure AD keys)
           │ ✓ Expiration (not expired)
           │
           ├─── ✅ Valid ────┐    ❌ Invalid ───┐
           │                 │                   │
           ▼                 ▼                   ▼
    ┌──────────────┐  ┌──────────────┐  ┌──────────────┐
    │  Controller  │  │  200 OK      │  │  401/403     │
    │  Executes    │  │  Returns     │  │  Unauthorized│
    │  Endpoint    │  │  Data        │  │  Forbidden   │
    └──────────────┘  └──────────────┘  └──────────────┘

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Step-by-Step Authorization Process

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Step 1: Developer Opens Swagger UI

What happens:

• Developer navigates to Swagger UI endpoint
  • ApiService: http://localhost:7532/swagger (local dev)
  • IntegrationServiceAPI: http://localhost:7098/swagger (local dev)
• Swagger UI loads, showing all available API endpoints
• All endpoints show a lock icon 🔒 indicating authorization required

Who's involved:

• Developer (Browser)
• Swagger UI

What you see:

• List of all API endpoints organized by controller
• Open lock icons (grayed out) indicating authentication required
• "Authorize" button in the top-right corner

Result:

• Swagger UI is loaded but cannot test endpoints yet
• Need to authenticate first

...

Step 2: Click "Authorize" Button

What happens:

• Developer clicks the "Authorize" button (or clicks a lock icon)
• Modal dialog appears showing available security schemes
• Shows OAuth2 (Authorization Code with PKCE) security scheme
• Displays the required scope for the API

Who's involved:

• Developer
• Swagger UI

Authorization modal shows:

For ApiService:

oauth2 (OAuth2, authorizationCode with PKCE)
Scopes:
  api://4dad5d62-dc8c-4378-8bd0-ae736a4d73fe/access_as_user - Access API as user

For IntegrationServiceAPI:

oauth2 (OAuth2, authorizationCode with PKCE)
Scopes:
  api://bd5100ee-af63-4880-8c60-47d4207d60c1/access_as_user - Access Integration API as user

Result:

• Developer sees what permissions will be requested
• Ready to start OAuth2 flow

...

Step 3: Initiate OAuth2 Flow

What happens:

• Developer clicks "Authorize" in the modal
• Swagger UI starts the OAuth2 Authorization Code flow
• Browser redirects to Microsoft Entra ID login page
• Security code (PKCE) generated automatically

Who's involved:

• Swagger UI
• Microsoft Entra ID

What's sent to Microsoft:

• Swagger client ID
• Which API scope is needed
• Security challenge code (PKCE)
• Where to redirect back after login

Result:

• Browser redirected to Microsoft login page

...

Step 4: Developer Enters Credentials

What happens:

• Developer sees Microsoft login page
• Enters email (e.g., developer@example.com)
• Enters password
• Completes MFA challenge (required)
• (First time only) Consents to app permissions

Who's involved:

• Developer
• Microsoft Entra ID

What Microsoft validates:

• User credentials are correct
• User has access to the tenant
• User consents to requested scope

Result:

• Microsoft Entra ID validates credentials
• If valid → Proceed to Step 5
• If invalid → Show error, retry

...

Step 5: Authorization Code Returned

What happens:

• Microsoft Entra ID generates a one-time authorization code
• Redirects browser back to Swagger's callback page
• Code is valid for 10 minutes

Who's involved:

• Microsoft Entra ID
• Swagger UI

Result:

• Swagger UI receives authorization code
• Ready to exchange code for access token

...

Step 6: Exchange Code for Access Token

What happens:

• Swagger UI automatically exchanges authorization code for access token
• Sends code + PKCE verifier to Microsoft token endpoint
• Microsoft validates code and PKCE verifier
• Returns access token

Who's involved:

• Swagger UI
• Microsoft Entra ID

What's in the access token:

• Who issued it (Microsoft Entra ID)
• Who it's for (ApiService or IntegrationServiceAPI)
• Developer's identity (name and email)
• What permissions are granted
• When it expires (1 hour)

Result:

• Swagger UI now has access token (valid for 1 hour)
• Authorization modal closes
• Lock icons change to closed locks (black) indicating authorized
• Developer can now test endpoints

...

Step 7: Testing an API Endpoint

What happens (every time developer tests an endpoint):

1. Developer selects an endpoint (e.g., GET /api/v1/WorkOrder/Overview)
2. Clicks "Try it out"
3. Fills in any required parameters
4. Clicks "Execute"
5. Swagger UI automatically adds the access token to the request
6. Request sent to the API

Who's involved:

• Developer
• Swagger UI
• ApiService or IntegrationServiceAPI

Result:

• API receives authenticated request with token
• Token proves developer's identity and permissions

...

Step 8: API Validates Token

What happens (on ApiService/IntegrationServiceAPI):

1. API receives request with token
2. Authentication middleware examines the token
3. Checks who issued the token (Azure AD)
4. Validates token is authentic:
   • Signature is valid (proves token came from Azure AD)
   • Issuer matches (correct Azure AD tenant)
   • Audience matches (token is for this specific API)
   • Not expired (within 1-hour lifetime)
5. If all checks pass → Request continues to controller
6. If any check fails → Return 401 Unauthorized

Who's involved:

• ApiService or IntegrationServiceAPI
• JWT Authentication Middleware
• Microsoft Entra ID (public keys used for validation)

What's validated:

• Token signature: Proves it's authentic and not forged
• Issuer: Confirms it came from Azure AD
• Audience: Ensures it's for the correct API
• Expiration: Checks it hasn't expired

Result:

• ✅ Valid token → Controller executes, returns response (200 OK)
• ❌ Invalid token → Authentication fails, returns 401 Unauthorized
• Swagger UI displays the response

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