Hi Sebastian,

In IPWB (https://github.com/oduwsdl/ipwb) we perform dechinking of the
chunked responses before pushing them to the IPFS (a content-addressable
file system) to leverage deduplication benefits. When we do that, we make
necessary modifications in corresponding headers to make sure the archival
replay behaves properly. However, in pour case we are throwing the original
information away as we are not using WARCs for replay, but ingesting WARC
records to populate IPFS for replay. If we can agree on a way to preserve
this information, we will be happy to adopt to it in IPWB.

As far as I know X-Archive-Orig-* headers are replay specific. They do not
exist in WARC records, but added later at the replay time. While there is
nothing stopping us from utilizing that style of headers, I wonder current
archival replay systems (such as Open Wayback and PyWB) will relay them as
X-Archive-Orig-X-Archive-Orig-* headers instead (I might be wrong here). We
can perhaps think of a different and more descriptive naming for situations
like this (for example, X-Capture-Orig-* or X-WARC-Transform-Orig-*).

WARC file allow a means to store variants of a record and associate them,
so in theory it is possible to have one record in the original form and
another one that is canonicalized from it. However, this will lose the
deduplication benefit.

IIPC's slack has a #warc channel where we discuss on the WARC
specifications. We had some conversation around HTTP2 recently, should we
preserve the original binary bytes as they arrive or the post-processed
data. I think you might want to discuss this transformation matter there
and see what others have to say about it.

Best,

--
Sawood Alam
Department of Computer Science
Old Dominion University
Norfolk VA 23529



On Wed, Aug 22, 2018 at 5:22 AM Sebastian Nagel <[email protected]>
wrote:

> Common Crawl stores the payload uncompressed and unchunked to leverage
> processing of WARC files by users on various platforms on programming
> languages. To avoid potential errors by the WARC processors this requires
> to remove resp. change the HTTP headers "Content-Length",
> "Content-Encoding" and "Transfer-Encoding".
>
> Now I want to preserve the original headers in a safe but transparent way.
> Is the preservation of original and rewritten HTTP headers in WARC files a
> valid use case for the X-Archive-Orig- header prefix, or is it thought only
> for wayback machines when serving captures over HTTP?
>
> Thanks,
> Sebastian
>
> --
> You received this message because you are subscribed to the Google Groups
> "openwayback-dev" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to [email protected].
> Visit this group at https://groups.google.com/group/openwayback-dev.
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/openwayback-dev/371f84db-0486-4f7d-860a-a37d7d3c06df%40googlegroups.com
> <https://groups.google.com/d/msgid/openwayback-dev/371f84db-0486-4f7d-860a-a37d7d3c06df%40googlegroups.com?utm_medium=email&utm_source=footer>
> .
> For more options, visit https://groups.google.com/d/optout.
>

-- 
You received this message because you are subscribed to the Google Groups 
"openwayback-dev" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to [email protected].
Visit this group at https://groups.google.com/group/openwayback-dev.
To view this discussion on the web visit 
https://groups.google.com/d/msgid/openwayback-dev/CALOnmf-AiZrHyTHWKQvFTBsOPcHoO4y4QXzPrMWzKNPr7f8jug%40mail.gmail.com.
For more options, visit https://groups.google.com/d/optout.

Reply via email to