[Nix-dev] Fetching variable and unpredictable URL download link

[Harald van Dijk]

Hi,

The problem here is not with the file names, but that you don't actually 
get the same file every time. The file is generated by the server 
on-the-fly, and the mtimes of the files in the download you get depend 
on the precise moment you download it, as you can tell by inspecting the 
output of

   tar tvf $download

This is fundamentally incompatible with any package manager that checks 
that source archives are downloaded correctly.

The original website

 
http://lancre.ribbrock.org/en/binabit_en/wmsmpmon_en/wmsmpmon-changelog_en.html

appears to link to a stable archive that you should be able to use instead.

Cheers,
Harald van Dijk

On 03/01/2015 04:21 PM, Anderson Torres wrote:
> Hello, Nixers!
>
> How can I "fetchurl" a variable url?
>
> When I download a dockapp from Windowmaker site, like
>
> "http://windowmaker.org/dockapps/?download=wmSMPmon-3.1.tar.gz",
>
> it in fact downloads something like "wmSMPmon-${a long string of
> chars, like a checksum}.tar.gz". And the long string is unpredictable.
>
> And when I run nix-prefetch-url
> "http://windowmaker.org/dockapps/?download=wmSMPmon-3.1.tar.gz" more
> than once, it just outputs different hashes:
>
>> nix-prefetch-url http://windowmaker.org/dockapps/\?download\=wmSMPmon-3.1.tar.gz
>    % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
>                                   Dload  Upload   Total   Spent    Left  Speed
>    0     0    0     0    0     0      0      0 --:--:--  0:00:01 --:--:--     0
> 100 24113    0 24113    0     0   3809      0 --:--:--  0:00:06 --:--:--  5139
> path is ‘/nix/store/lqri8zgmwz3mbf3q07kp62zl81bc6fpq-?download=wmSMPmon-3.1.tar.gz’
> 104bcfj4j0vlnr4v1fzahgj9amccn1aq7rjcpy1jyqnq6lbrmc3g
>
>> nix-prefetch-url http://windowmaker.org/dockapps/\?download\=wmSMPmon-3.1.tar.gz
>    % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
>                                   Dload  Upload   Total   Spent    Left  Speed
>    0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0
> 100 24110    0 24110    0     0   3193      0 --:--:--  0:00:07 --:--:--  3985
> path is ‘/nix/store/f2b7rksjfh6ajddjhx09xb0jzc04jxg9-?download=wmSMPmon-3.1.tar.gz’
> 1s01whvf51jrwdmrk3bdgysaa2rzmh56c9p0kv3ydxijaagvqi2x
>
> How can I download it?
> _______________________________________________
> nix-dev mailing list
> nix-dev at lists.science.uu.nl
> http://lists.science.uu.nl/mailman/listinfo/nix-dev
>