Today’s tech tip
The ETag (Entity Tag) header is part of the HTTP protocol, serving as a unique identifier for a specific version of a resource, just like a checksum for a file. It allows servers and browsers to determine whether the version of the content they have is up-to-date.
đź’ˇ Why ETag Matters
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Detecting Mid-Air Collisions: They help in detecting “mid-air collisions” - scenarios where a resource is being edited simultaneously from different locations. By comparing ETags, we can prevent overwriting changes unknowingly.
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Saving Data & Enhancing Performance: ETags can help revalidate stale responses. Instead of downloading the entire resource again, clients can send the ETag value to the server. If the content hasn’t changed (the ETag matches), the server responds with a 304 Not Modified status, indicating that the cached version is still valid. This process can significantly reduce bandwidth usage speed up content load times.
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