refetch

Refetch is the act of requesting fresh data from a source after a client has already retrieved and possibly cached information. It is commonly used in web and application development to ensure the displayed data remains current. Refetching can be triggered by user actions, such as pressing a refresh button or performing a pull-to-refresh gesture, or automatically through polling, on-focus revalidation, or other events.

In practice, many data-fetching libraries provide a function or method labeled refetch or revalidate that forces a new network request and updates the local cache with the latest data. The operation may bypass the cache or respect configured cache policies, depending on the implementation. Refetching typically involves handling loading states and errors, and it may replace cached data if the server data has changed.

Caching strategies influence refetch behavior. For example, stale-while-revalidate shows cached data immediately while fetching fresh results in the background, whereas time-based or event-based invalidation triggers refetches at defined intervals or in response to specific events. Some systems distinguish between soft refreshes, which update in the background, and hard refreshes, which may block interaction until new data arrives.

In APIs, refetch generally means issuing a GET request to retrieve the resource again, potentially with parameters to fetch related data. In data pipelines, refetching can denote re-reading data from upstream sources after updates.

Overall, refetching is a standard mechanism to maintain data accuracy and timeliness in interactive applications and data workflows, balancing immediacy, performance, and resource usage.