Idempotency
An action that gives the same result no matter how many times it is repeated.
Definition
An idempotent operation can safely be repeated: doing it twice has the same effect as doing it once. Payment and order systems rely on this to protect users from retries, refreshes and double taps. Testers check it by repeating actions on purpose.
In practice
Refreshing the "Order confirmed" page or tapping "Pay" twice should still result in exactly one order and one charge.
Learn it in context
Lessons that use this term.
- Shopping Cart and CheckoutFeatures
- Push NotificationsFeatures
- Interruptions (Calls, SMS, Alarms)Mobile
- Network ConditionsMobile
- API Testing with PostmanWeb
- API Testing in Depth: Auth, Negative Tests and Data ChecksWeb
- State Transition TestingFundamentals
- Proxy Tools: Charles and ProxymanMobile
- Offline ModeFeatures
- In-App Purchases and SubscriptionsFeatures