Filestack CDN shares cache across signed policies; expiry does not bust it

TL;DR

For fresh content during testing, use the /cache=false/ task sparingly, and for production freshness use the cache=expiry task with a value in seconds. Do not rely on signed-URL expiry to revoke a cached file; the cache entry is shared across policies.

Steps

1. Do not rely on signed-URL expiry to revoke a cached file; the cache entry is shared across policies. For fresh content during testing, use the /cache=false/ task sparingly, and for production freshness use the cache=expiry task with a value in seconds. Remember that every transformation variant is a separate 30-day cache entry.

When to use

You are seeing this: Do not rely on signed-URL expiry to revoke a cached file; the cache entry is shared across policies. Use this skill when you run into "Filestack CDN shares cache across signed policies; expiry does not bust it".

When not to use

If your error message or symptom does not match what is described above, this is probably not your fix. Search for your exact error text instead of forcing this one to fit.

Versions

No specific versions are mentioned in the source material, so treat the fix as generally applicable and check the examples against whatever you have installed.

Why this happens

The original report does not dig into a root cause. It documents the symptom and the fix that resolved it.

Edge cases

• Remember that every transformation variant is a separate 30-day cache entry.

Source: Web (Filestack blog, CDN delivery explained): the Filestack CDN caches each unique URL for 30 days on first request, and each transformed variant is its own cache entry. The subtle part: security policies and signatures are excluded from URL uniqueness, so two requests for the same file with different signed policies share one cache entry. Expiring a signed URL does not expire the cached file, and bypassing with /cache=false/ skips the optimization layer and counts against your transformation quota.

Verified resolution: Do not rely on signed-URL expiry to revoke a cached file; the cache entry is shared across policies. For fresh content during testing, use the /cache=false/ task sparingly, and for production freshness use the cache=expiry task with a value in seconds. Remember that every transformation variant is a separate 30-day cache entry.

Source URL: https://blog.filestack.com/how-the-filestack-cdn-delivers-your-files-fast-across-the-globe/?ref=hackernoon.com