[tauruslib-devel] odo-compatible URIs (Was: Re: URIs)

[Carlos P. <cpa...@ce...>]

Hi Armando,

I hope you do not mind me posting my response to the taurus mailing list 
since I think this can be an interesting topic for discussion with all 
the developers of Taurus. See my reply below.

On Wed 22 June 2016 15:07:51 V. Armando Solé wrote:
> Carlos,
> 
> I have just seen your slides. Concerning URIs, can you try to be
> compatible with pydata URIs behore Taurus4 is already deployed? We
> intend to follow their way in order not to reinvent things.
> 
> http://odo.pydata.org/en/latest/uri.html
> 
> Best regards,
> 
> Armando


I did not know odo. Thanks for pointing to it. 

I will look into it later in more detail, but on a first look, it seems 
that there are no collisions with the *existing* URIs in Taurus. So it 
definitely seems a good idea to try to follow their conventions for the 
new schemes.

BUT I am worried because while in Taurus TEP3 [1] we explicitly made 
changes to enforce  RFC3986 [2], odo / PyData [3] seems not tho comply 
with it:

- odo uses "://" for specifying protocols. RFC3986 states that the 
protocol (scheme name) is separated by ":" and the "//" is actually a 
prefix for the authority part, not a separator. In practice this implies 
that if no authority is given, there must not be "//". So the "URI"
`hdfstore://myfile.h5::/data/path` is not RFC3986-compliant (I am 
assuming here that "myfile.h5" is part of the URI path, not the 
"authority").

-RFC3986 also says that authority and path *must* be separated
by "/". This means that "hostname" in `postgresql://hostname::tablename` 
is actually part of the path when it seems to me that it would make more 
sense as part of the authority.

Still, I think it might be possible to support odo to a large extent in 
taurus (and in fact, I am thinking that many new taurus schemes could be 
built upon odo itself).

But this needs to be looked at with some care.

Cheers,

Carlos


[1] https://sourceforge.net/p/tauruslib/wiki/TEP3 
[2] https://tools.ietf.org/html/rfc3986
[3] http://odo.pydata.org/en/latest/uri.html



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