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Hello,<br>
<br>
We are currently investigating the use of Varnish for our
infrastructure. In the software we build, we depend on the
If-None-Match header and the use of ETAG's.<br>
The API we have created creates mainly JSON objects, and they differ
in size from a few hundreds of bytes to several megabytes. A lot of
these JSON objects are perfectly suited for caching, until someone
changes a parameter and this can happen at any moment. That is also
why we keep a record of all ETAG's and we invalidate them when
needed. <br>
<br>
What we would like to do is cache created JSON object in front of
our production environment and when someone requests the same
calculation that someone else has requested before and the ETAG is
still valid, send out the cached object. But this basicly implies
the following workflow:<br>
<br>
<img src="cid:part1.FFE7E35F.41FA4089@betterbe.com" alt=""><br>
<br>
Somewhere I found an old Trac Wiki document that describes something
like this, but I can't figure out if this has been implemented or
not.<br>
<a class="moz-txt-link-freetext" href="https://www.varnish-cache.org/trac/wiki/BackendConditionalRequests?version=8">https://www.varnish-cache.org/trac/wiki/BackendConditionalRequests?version=8</a><br>
<br>
Could someone tell me if the workflow I describe is possible? My
first tests tell me that in the default setup it isn't working like
this.<br>
<br>
Best regards,<br>
Jan Hugo Prins<br>
<br>
<br>
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