B2C Commerce stores static storefront content in eCDN cache or the web tier static
content cache.
All content cached by eCDN is served using a unique URL. Cache purging a CDN on top of
URLs from B2C Commerce isn’t necessary, because the system updates the URL when
uploading new content. Aside from replicating environments to clear the cache of any
static content, no action is required.
When working with eCDN cache, keep the following in mind:
- eCDN uses the Cache-Control header to persist a file in cache until that TTL
expires. After the cache header expires, eCDN retrieves the new resource. eCDN caches
based on the value set by the cache headers. If these headers aren’t set, the default
value of 30 days is enforced.
-
The web adapter configures web pages using static assets from both eCDN and web tier
cache sources. Regardless of the cache location, web tier or eCDN, each static content
asset on your storefront is assigned a fingerprint value. For example, consider the
following URL:
https://www.samplecustomer.com/dis/dw/image/v2/XXXX_PRD/on/demandware.static/-/Sites-customer-main-product/default/dwabb3a337/images/hi-res/shoes.jpg?sw=200=200=fitm=png>.
The value dwabb3a337 is the asset fingerprint. The fingerprint
provides a unique identifier for the asset.
- Updates to static cache occur at intervals you set. If necessary, you can update an
asset held in static cache before the cache interval expiration. The process doesn’t
require cache to be cleared, and can be completed without requesting a support
ticket.
To clear eCDN cache:
-
Upload the updated asset to your storefront POD.
When an asset is updated on the POD, the system generates a new fingerprint
value for that asset. Changing the fingerprint also changes the URL of the updated
asset. When your storefront requests the updated static asset, the URL request
returns a miss in eCDN and web tier cache. This response occurs because the
fingerprint is different, and the CDN doesn’t recognize the new and old asset as the
same. The missed request with the new fingerprint is then directed to the POD, the
asset is then retrieved and cached with the new URL.
Note: All content assets in
cache are refreshed, excluding the old content updated in this process. The update
content is assigned a new fingerprint that results in a new URL for the
asset.
-
Refresh your site in the browser and confirm that the updated asset appears as
expected.
If the updated asset doesn’t appear in your browser after updating content, you can
manually invalidate the Application Tier cache. Though it’s rare, the asset not
appearing means that something went wrong with the cache clearing process.
- Clear the cache:
- To clear the Business Manager Site cache, navigate to , and click Invalidate where
applicable.
- To invalidate the cache for a specific site, navigate to and click Invalidate where
applicable.
- Refresh the site in your browser, and confirm that the updated asset appears as
expected.