> Message: 3
> Date: Fri, 12 Dec 2008 11:45:15 -0800
> From: Dan Fandrich <dan_at_coneharvesters.com>
> Subject: Re: Patch for Metalink Support
> To: curl-users_at_cool.haxx.se
> Message-ID: <20081212194513.GB12193_at_coneharvesters.com>
> Content-Type: text/plain; charset=us-ascii
>
> On Sat, Dec 13, 2008 at 12:31:29AM +0900, Tatsuhiro Tsujikawa wrote:
>> I made a patch to add very basic Metalink support to curl command-line
>> tool. The patch is made against curl-7.19.2. Although the patch is still
>> rather experimental, it provides basic fail over functionality.
>
> This is a neat patch, but IMHO it doesn't belong in the curl command line
> client. It adds functionality that goes well beyond what curl is designed
> for and the UNIX philosophy behind it: to do one thing and do it well,
> which is to transfer individual URLs from/to individual sites
> and to allow all manner of tweaking that behaviour. That's why it
> doesn't do HTML parsing, remote URL globbing, recursive transfers,
> PAC proxy configuration, etc.

Dan, thanks for taking the time to check out the patch.
obviously, your opinion is valued here. I understand where you're coming from...

the philosophy behind Metalink is that we want a download to succeed
if there is any way possible for it to. if a server goes down, switch
over to another. if there's an error in transfer, detect it and
re-get that chunk, etc.
where curl may be for tweaking & manual options galore, we want people
to have an error free completed download with no thought or
intervention necessary. :)

perhaps Metalink doesn't mesh up w/ curl. like you said, we're
different, but maybe there's a place where we intersect. maybe
metalink falls into "a busload of other useful tricks" category, from
the description of curl on the site.

as much as I'd like to see it in curl, I hope this isn't a round peg,
square hole deal. I think it'd be useful to some people. but I could
be wrong.

Daniel Stenberg has also blogged about this and added to the feature
bounty: http://daniel.haxx.se/blog/2008/11/09/metalink-in-curl-bounty/

> Metalink support is designed for something other than what curl's primary
> mission is about. An indication of this is that of curl's 128 options, half
> become irrelevant (and even more are marginally relevant) when doing
> Metalink transfers. Adding two additional library dependencies to curl
> is also an issue.

a great point! as I stated above, Metalink does aim to simplify
things. this may be different from curl's primary mission, but if curl
can also offered simplified completed transfers in many cases, then
that could be nice too.

I don't know what can be done about the two additional libraries, &
agree that's an issue.

> A curl-based Metalink downloader is a great idea, but as a separate program.
> Of course, JMOOC, YMMV.

Metadl ( http://hampus.vox.nu/metadl/ ), used in Wubi by Ubuntu is one
such Metalink downloader that uses libcurl.

-- 
(( Anthony Bryan ... Metalink [ http://www.metalinker.org ]
  )) Easier, More Reliable, Self Healing Downloads
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