K6 Authentication
You set up k6 authentication by passing tokens, cookies, or login details in test requests. This lets your load test scripts log in to private apps and APIs. Most teams store these secrets in local files or runner variables before a test. When those test roles have broad rights, one bad script can delete real data. How k6 authentication works in load tests Load tests must act like real users when they hit private endpoints. The test tool needs a way to prove who it is on every call. Teams can
Multi-Factor Authentication (MFA): the complete guide
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You set up k6 authentication by passing tokens, cookies, or login details in test requests. This lets your load test scripts log in to private apps and APIs. Most teams store these secrets in local files or runner variables before a test. When those test roles have broad rights, one bad script can delete real data.
How k6 authentication works in load tests
Load tests must act like real users when they hit private endpoints. The test tool needs a way to prove who it is on every call. Teams can use basic user logins, session cookies, or bearer tokens for this job. The right choice depends on how your target app checks user identity.
Most scripts use a setup step to log in before the main load starts. That step sends a user name and password to the login server once. The server sends back a token or session cookie in the reply. The script saves that value and shares it with all virtual users.
Each virtual user then adds that token to the header of every HTTP call. Some teams skip the shared setup step to test the login server itself. In that case, each virtual user logs in on its own during the run. They pull unique login rows from a shared data file so accounts do not clash.
Cloud test runners also need a key to send test metrics back home. Engineers store that API key in the runner machine or local shell variables. This keeps secret keys out of the source code repo while tests run.
What native k6 authentication solves and leaves open
Built-in login methods solve the basic problem of reaching protected API routes. Your scripts can pass through the front door and test real app logic. Cookie jars and header maps make it easy to keep sessions alive under load. Storing secrets in shell variables also keeps raw passwords out of Git commits.
Yet this native setup only controls how the script logs in at the start. It does not check what the test requests do once they are inside. A token with write rights can still wipe tables or change user records. If a script hits a production URL by mistake, the app trusts that token.
Multi-Factor Authentication (MFA): architecture patterns and best practices
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Sharing test keys across a team creates another gap during daily work. Every engineer who runs the test needs read access to the secret variables. Static service tokens often stay valid for months without a rotation schedule. Audit logs only show one shared test account instead of the person who ran it.
Data exposure is also a risk when load tests read from staging databases. Error logs in the test output can print full API replies to the screen. Those replies might hold real emails, phone numbers, or card numbers from test records. Native script settings do not mask those fields when printing debug output.
How to keep load test credentials safe
Teams should scope test accounts to the smallest set of rights possible. Create a dedicated role that can only read or write in isolated test spaces. Never reuse an admin token just to make a load script work faster. Set tokens to expire right after the test window ends.
Separate your login setup logic from the main test scenarios in your repo. Pull all secrets from a secure store at runtime instead of local text files. Check that target host names match your test servers before sending any login call. Turn off verbose body logging when tests run against databases with sensitive records.
Govern statements and responses across databases and APIs
Good config and scoped roles are needed setup. They do not check single queries in flight or mask sensitive fields in returned rows. Across Postgres, MySQL, SQL Server, MongoDB, ClickHouse, Kubernetes APIs, SSH, and internal HTTP endpoints, hoop.dev runs beside each supported service as an open-source proxy, a sidecar for your database or API.
First, hoop.dev guardrails block banned queries before they run. Then hoop.dev data masking rewrites matched sensitive values in responses in memory. The audit trail records every statement and verdict per resource. Furthermore, hoop.dev holds SOC 2 Type II and is open source on GitHub.
Frequently asked questions
Should every virtual user log in on every test loop?
No, unless you want to stress test the login server itself. Logging in once during the setup phase saves time and avoids rate limits. Virtual users can then reuse that single token for the rest of the test.
How does the test tool handle session cookies during a run?
The tool keeps a separate cookie jar for each virtual user by default. When a server sends a cookie header, the virtual user saves it for later calls. You can also clear or set custom cookies between requests if your test needs it.
Where should teams store API tokens for automated test runs?
Store tokens in the secret manager of your CI runner rather than in script files. Pass those secrets into the test process as runtime variables when the job starts. Make sure your runner logs do not print those variables to the console.