Stage 3 · Build
Authentication & Authorization
Testing Auth
Test login failures, expired tokens, cookie flags, httptest middleware, and authorization boundaries.
7 min readBuilding Backend ApplicationsBuild
Why Test Auth
Authentication and authorization are the most security-sensitive parts of your application. A missed test case can mean a broken login, an expired token that still works, or a user accessing admin endpoints. Auth tests are not optional.
httptest Basics
Gohttptest-for-handler-testing.go
24 linesLn 1, Col 1Go
httptest creates fake requests and records responses. This lets you test handlers without starting a real server. The handler runs in-process, making tests fast.
Testing Login Failures
Gotable-driven-auth-tests.go
34 linesLn 1, Col 1Go
Table-driven tests cover all auth failure modes. Each case verifies the correct HTTP status code. This catches bugs where error handling is incomplete.
Testing Token Expiry
Gotesting-expired-tokens.go
39 linesLn 1, Col 1Go
Create tokens with past expiry dates to test rejection. Create tokens with future expiry dates to test acceptance. Both paths must be tested.
Testing Cookie Flags
Goverifying-cookie-security.go
36 linesLn 1, Col 1Go
Every cookie flag matters. HttpOnly prevents XSS. Secure prevents HTTP leakage. SameSite prevents CSRF. Test all of them.
Testing Authorization
Gotesting-role-based-access.go
36 linesLn 1, Col 1Go
Test every role against every protected endpoint. Verify that users cannot access admin resources and admins can access everything. This catches authorization bypass bugs.
Never skip auth tests
Auth bugs are the most common security vulnerabilities. Every login path, token validation, and role check needs a test. Missing one test case can mean a broken authentication bypass.
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