Re: Symlink redirection breaks FTP site re-organisation

On Tue, Jun 7, 2016 at 10:38 AM, Magnus Hagander <magnus@hagander.net> wrote:
>
>
> On Mon, Jun 6, 2016 at 5:19 PM, Dave Page <dpage@pgadmin.org> wrote:
>>
>> On Mon, Jun 6, 2016 at 4:02 PM, Magnus Hagander <magnus@hagander.net>
>> wrote:
>> >
>> >
>> > On Mon, Jun 6, 2016 at 2:11 PM, Dave Page <dpage@pgadmin.org> wrote:
>> >>
>> >> Hi,
>> >>
>> >> Whilst re-organising the pgAdmin website in preparation for pgAdmin 4,
>> >> it became clear to me that the way we currently handle symlinks on the
>> >> website FTP browser is broken. For example, the current pgAdmin site
>> >> has URLs like:
>> >>
>> >> https://www.postgresql.org/pgadmin3/release/v1.22.1/...
>> >>
>> >> I want to change this to:
>> >>
>> >> https://www.postgresql.org/pgadmin/pgadmin3/v1.22.1/...
>> >>
>> >> Thus I renamed/symlinked the pgadmin3 dir on Fendaus and the release
>> >> dir on Paxsor (the pgAdmin master server), however, whilst when we
>> >> encounter a symlink in the browser we re-write it to the target (so
>> >> that: https://www.postgresql.org/pgadmin3/ is rewritten to
>> >> https://www.postgresql.org/pgadmin/), we don't handle anything deeper
>> >> than that, so https://www.postgresql.org/pgadmin/release is a 404,
>> >> never mind anything below it.
>> >>
>> >> So, I'm thinking that we need to have the website stop rewriting the
>> >> URLs, or at least generate the index pages under both paths, as you
>> >> would see if you traversed the filesystem itself.
>> >>
>> >> In doing this, I think we should also use a different icon for
>> >> symlinks, so users can see that they're following a path (and maybe
>> >> display the filename as "pgadmin3 -> pgadmin" as well).
>> >>
>> >> Thoughts?
>> >
>> >
>> > Every single one of those URLs is a 404... Which makes the discussion a
>> > bit
>> > hard to follow. Is it correct to just inject a "/ftp/" in each case, or
>> > are
>> > there other subtleties to consider?
>>
>> Err, yeah. Though I had to backout my changes of course as it broken
>> links all over the place because of this problem.
>>
>> Here's a current example though:
>>
>> https://www.postgresql.org/ftp/pgadmin3/ - This is a "real" directory.
>> https://www.postgresql.org/ftp/pgadmin/ - This is a symlink to
>> pgadmin3 (i.e. the on-page link is to the URL above)
>>
>> On a filesystem, the following paths are effectively the same:
>>
>> /pub/pgadmin3/release/v1.22.1/
>> /pub/pgadmin/release/v1.22.1/
>>
>> However, not on the website:
>>
>> https://www.postgresql.org/ftp/pgadmin3/release/v1.22.1/ (OK)
>> https://www.postgresql.org/ftp/pgadmin/release/v1.22.1/ (404)
>>
>> This prevents me properly fixing the directory names, and using
>> symlinks for backwards-compatibility.
>>
>
> Ah, gotcha, no I'm following.
>
> I agree that a good way forward is to stop rewriting the URLs. However, I
> think the proper thing to do is to detect the case and generate a real http
> redirect response for those cases where there's a symlink in the path, and
> not generating the indexes in two different places.
>
> E.g. the link would still point to /ftp/pgadmin/, but hitting that would
> give you a 301 code sending you to /ftp/pgadmin3/.

Yes, that seems reasonable.

> There's no reason that can't fairly easily be made to work for deep links as
> well - and if we're going to change this around we should get both of those
> fixed at once.

Yeah.

-- 
Dave Page
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Twitter: @pgsnake

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