Re: StreamRDF.base()

[Andy Seaborne]

On 15/08/2019 13:02, Claude Warren wrote:

Learn something new every day...

On Wed, Aug 14, 2019 at 5:44 PM Andy Seaborne  wrote:





(and it is technically wrong to have a # in the base)



so as a base "http://example.com/myfile.txt#; is incorrect but "
http://example.com/myfile.txt/; is correct?


Legal.

They are completely different URIs. "/" means something in http URIs.

Fragments are within the document named.
Base URIs are like HTTP requests which also do not have a fragement,

Resolving  against base URIs:

  http://example/dir/
  http://example/dir/file

and it's the same outcome.

http://example/dir/one

https://twitter.com/AndySeaborne/status/1156227576257482754

RFC 3986, section 5.2

5.2.3 - "Base.fragment" is not mentioned.

Jena does cope with # in the base - it drops it as per 5.2, 5.2.3

The only assignment is

T.fragment = R.fragment

(R being the relative URI being resolved, T the output)

Relative <#one> gives:

  http://example/dir/#one
  http://example/dir/file#'one




or technically does the last segment of the base need to be an NCName[1]?


"need" - no.

NCName is an XML-ism.

For RDF/XML it is a good idea - classes and properties can end up as XML 
qnames.





in which case "http://example.com/myfile.txt; but not "
http://example.com/myfile.txt#; or "http://example.com/myfile.txt/;

How does one create a technically correct base that will convert

to


 can't become 

Resolution can't introduce a fragment that isn't in the relative URI to 
start with. <#one> works.




or


?  Or is that just not possible?

Thx,
Claude


[1] https://www.w3.org/TR/xml-names/#NT-NCName

Re: StreamRDF.base()

[Claude Warren]

Learn something new every day...

On Wed, Aug 14, 2019 at 5:44 PM Andy Seaborne  wrote:

>
>
>
> (and it is technically wrong to have a # in the base)
>
>
so as a base "http://example.com/myfile.txt#; is incorrect but "
http://example.com/myfile.txt/; is correct?

or technically does the last segment of the base need to be an NCName[1]?
in which case "http://example.com/myfile.txt; but not "
http://example.com/myfile.txt#; or "http://example.com/myfile.txt/;

How does one create a technically correct base that will convert

to

or


?  Or is that just not possible?

Thx,
Claude


[1] https://www.w3.org/TR/xml-names/#NT-NCName
-- 
I like: Like Like - The likeliest place on the web

LinkedIn: http://www.linkedin.com/in/claudewarren

Re: StreamRDF.base()

[Andy Seaborne]

On 14/08/2019 12:30, Martynas Jusevičius wrote:

And if I want hash URIs such as <https://localhost/ontology#term> then
I need to do

 IRIResolver.create("https://localhost/ontology;).resolve("#term")


IRIResolver resolver = IRIResolver.create("https://localhost/ontology;);
...
resolver.resolve("#term");




rather than

 IRIResolver.create("https://localhost/ontology#;).resolve("term")

which would produce <https://localhost/term> instead, correct?


Yes.

Resolution is not concat.

(and it is technically wrong to have a # in the base)




On Wed, Aug 14, 2019 at 12:32 PM Andy Seaborne  wrote:


Yes.

More efficient is to create a resolver with IRIResolver.create and use
that. Includes caching of resolved strings.

See the turtle parser.

  Andy

On 14/08/2019 11:28, Martynas Jusevičius wrote:

OK, more or less what I suspected.

And IRIResolver.resolve(String relStr, String baseStr) can be used by
the parser for said URI resolution?
https://jena.apache.org/documentation/javadoc/arq/org/apache/jena/riot/system/IRIResolver.html#resolve-java.lang.String-java.lang.String-

So far I'm not implementing a proper ReaderRIOT yet, just doing some
conversion to RDF.

On Wed, Aug 14, 2019 at 12:13 PM Andy Seaborne  wrote:


StreamRDF is an interface called by parsers (and other things) based on
what it sees.

If in, say Turtle, teh pasrer sees a "BASE" then base(...) is called.

StreamRDF (it is an interface) does not do anything - its a stream of
incoming RDF for the implementation to deal with.

StreamRDFLib.writer writes N-quads.  No way to say "BASE".

Triples sent to triple() should be already resolved - a parser
responsibility.

   Andy

On 14/08/2019 09:28, Claude Warren wrote:

The StreamRDF just passed the base() argument on to the sink so that the
sink would have the base in order to set create the FQ URI from local
URIs.

StreamRDFLib simply ignores the base() call.


Did you mean StreamRDFBase?

StreamRDFLib is a colelction of fucntiosn and isn't itself does not have
the StreamRDF interface.


   I assume this is because it
is intended to process fully qualified RDF.

I think the assumption is that if you are streaming into the graph you
would need the base() to resolve any inbound local URIs while if you are
streaming out from the graph the URIs are already fully resolved.

I didn't write this code so I am not certain but if that is the case
perhaps we should note it in the javadocs.

I do note that StreamRDF says it is for output, in which case I am not
certain why the base() is needed at all.

Claude



On Tue, Aug 13, 2019 at 11:46 PM Martynas Jusevičius 
wrote:


Hi,

I'm trying to understand what the purpose/usage of StreamRDF.base() is.

Isn't it supposed to set the base URI that relative URIs in the stream
resolve against?

I've made a simple test:

   StreamRDF rdfStream = StreamRDFLib.writer(new BufferedWriter(new
OutputStreamWriter(System.out)));
   rdfStream.start();
   rdfStream.base("http://localhost/;);
   rdfStream.triple(new Triple(NodeFactory.createBlankNode(),
NodeFactory.createURI("relative"), NodeFactory.createBlankNode()));
   rdfStream.finish();

The output I get:

_:Bf410fc50X2De0baX2D464eX2D996eX2Dbb3207090baa 
_:B4b65b796X2D3561X2D4bf3X2Dbf31X2D1154aac0c816 .

Why is the property URI  and not <http://localhost/relative>?
Doesn't that make the output invalid N-Triples? Or am I writing it wrong?

Martynas
atomgraph.com

Re: StreamRDF.base()

[Martynas Jusevičius]

And if I want hash URIs such as <https://localhost/ontology#term> then
I need to do

IRIResolver.create("https://localhost/ontology;).resolve("#term")

rather than

IRIResolver.create("https://localhost/ontology#;).resolve("term")

which would produce <https://localhost/term> instead, correct?

On Wed, Aug 14, 2019 at 12:32 PM Andy Seaborne  wrote:
>
> Yes.
>
> More efficient is to create a resolver with IRIResolver.create and use
> that. Includes caching of resolved strings.
>
> See the turtle parser.
>
>  Andy
>
> On 14/08/2019 11:28, Martynas Jusevičius wrote:
> > OK, more or less what I suspected.
> >
> > And IRIResolver.resolve(String relStr, String baseStr) can be used by
> > the parser for said URI resolution?
> > https://jena.apache.org/documentation/javadoc/arq/org/apache/jena/riot/system/IRIResolver.html#resolve-java.lang.String-java.lang.String-
> >
> > So far I'm not implementing a proper ReaderRIOT yet, just doing some
> > conversion to RDF.
> >
> > On Wed, Aug 14, 2019 at 12:13 PM Andy Seaborne  wrote:
> >>
> >> StreamRDF is an interface called by parsers (and other things) based on
> >> what it sees.
> >>
> >> If in, say Turtle, teh pasrer sees a "BASE" then base(...) is called.
> >>
> >> StreamRDF (it is an interface) does not do anything - its a stream of
> >> incoming RDF for the implementation to deal with.
> >>
> >> StreamRDFLib.writer writes N-quads.  No way to say "BASE".
> >>
> >> Triples sent to triple() should be already resolved - a parser
> >> responsibility.
> >>
> >>   Andy
> >>
> >> On 14/08/2019 09:28, Claude Warren wrote:
> >>> The StreamRDF just passed the base() argument on to the sink so that the
> >>> sink would have the base in order to set create the FQ URI from local
> >>> URIs.
> >>>
> >>> StreamRDFLib simply ignores the base() call.
> >>
> >> Did you mean StreamRDFBase?
> >>
> >> StreamRDFLib is a colelction of fucntiosn and isn't itself does not have
> >> the StreamRDF interface.
> >>
> >>>   I assume this is because it
> >>> is intended to process fully qualified RDF.
> >>>
> >>> I think the assumption is that if you are streaming into the graph you
> >>> would need the base() to resolve any inbound local URIs while if you are
> >>> streaming out from the graph the URIs are already fully resolved.
> >>>
> >>> I didn't write this code so I am not certain but if that is the case
> >>> perhaps we should note it in the javadocs.
> >>>
> >>> I do note that StreamRDF says it is for output, in which case I am not
> >>> certain why the base() is needed at all.
> >>>
> >>> Claude
> >>>
> >>>
> >>>
> >>> On Tue, Aug 13, 2019 at 11:46 PM Martynas Jusevičius 
> >>> 
> >>> wrote:
> >>>
> >>>> Hi,
> >>>>
> >>>> I'm trying to understand what the purpose/usage of StreamRDF.base() is.
> >>>>
> >>>> Isn't it supposed to set the base URI that relative URIs in the stream
> >>>> resolve against?
> >>>>
> >>>> I've made a simple test:
> >>>>
> >>>>   StreamRDF rdfStream = StreamRDFLib.writer(new BufferedWriter(new
> >>>> OutputStreamWriter(System.out)));
> >>>>   rdfStream.start();
> >>>>   rdfStream.base("http://localhost/;);
> >>>>   rdfStream.triple(new Triple(NodeFactory.createBlankNode(),
> >>>> NodeFactory.createURI("relative"), NodeFactory.createBlankNode()));
> >>>>   rdfStream.finish();
> >>>>
> >>>> The output I get:
> >>>>
> >>>> _:Bf410fc50X2De0baX2D464eX2D996eX2Dbb3207090baa 
> >>>> _:B4b65b796X2D3561X2D4bf3X2Dbf31X2D1154aac0c816 .
> >>>>
> >>>> Why is the property URI  and not <http://localhost/relative>?
> >>>> Doesn't that make the output invalid N-Triples? Or am I writing it wrong?
> >>>>
> >>>> Martynas
> >>>> atomgraph.com
> >>>>
> >>>
> >>>

Re: StreamRDF.base()

[Andy Seaborne]

Yes.

More efficient is to create a resolver with IRIResolver.create and use 
that. Includes caching of resolved strings.


See the turtle parser.

Andy

On 14/08/2019 11:28, Martynas Jusevičius wrote:

OK, more or less what I suspected.

And IRIResolver.resolve(String relStr, String baseStr) can be used by
the parser for said URI resolution?
https://jena.apache.org/documentation/javadoc/arq/org/apache/jena/riot/system/IRIResolver.html#resolve-java.lang.String-java.lang.String-

So far I'm not implementing a proper ReaderRIOT yet, just doing some
conversion to RDF.

On Wed, Aug 14, 2019 at 12:13 PM Andy Seaborne  wrote:


StreamRDF is an interface called by parsers (and other things) based on
what it sees.

If in, say Turtle, teh pasrer sees a "BASE" then base(...) is called.

StreamRDF (it is an interface) does not do anything - its a stream of
incoming RDF for the implementation to deal with.

StreamRDFLib.writer writes N-quads.  No way to say "BASE".

Triples sent to triple() should be already resolved - a parser
responsibility.

  Andy

On 14/08/2019 09:28, Claude Warren wrote:

The StreamRDF just passed the base() argument on to the sink so that the
sink would have the base in order to set create the FQ URI from local
URIs.

StreamRDFLib simply ignores the base() call.


Did you mean StreamRDFBase?

StreamRDFLib is a colelction of fucntiosn and isn't itself does not have
the StreamRDF interface.


  I assume this is because it
is intended to process fully qualified RDF.

I think the assumption is that if you are streaming into the graph you
would need the base() to resolve any inbound local URIs while if you are
streaming out from the graph the URIs are already fully resolved.

I didn't write this code so I am not certain but if that is the case
perhaps we should note it in the javadocs.

I do note that StreamRDF says it is for output, in which case I am not
certain why the base() is needed at all.

Claude



On Tue, Aug 13, 2019 at 11:46 PM Martynas Jusevičius 
wrote:


Hi,

I'm trying to understand what the purpose/usage of StreamRDF.base() is.

Isn't it supposed to set the base URI that relative URIs in the stream
resolve against?

I've made a simple test:

  StreamRDF rdfStream = StreamRDFLib.writer(new BufferedWriter(new
OutputStreamWriter(System.out)));
  rdfStream.start();
  rdfStream.base("http://localhost/;);
  rdfStream.triple(new Triple(NodeFactory.createBlankNode(),
NodeFactory.createURI("relative"), NodeFactory.createBlankNode()));
  rdfStream.finish();

The output I get:

_:Bf410fc50X2De0baX2D464eX2D996eX2Dbb3207090baa 
_:B4b65b796X2D3561X2D4bf3X2Dbf31X2D1154aac0c816 .

Why is the property URI  and not <http://localhost/relative>?
Doesn't that make the output invalid N-Triples? Or am I writing it wrong?

Martynas
atomgraph.com

Re: StreamRDF.base()

[Martynas Jusevičius]

OK, more or less what I suspected.

And IRIResolver.resolve(String relStr, String baseStr) can be used by
the parser for said URI resolution?
https://jena.apache.org/documentation/javadoc/arq/org/apache/jena/riot/system/IRIResolver.html#resolve-java.lang.String-java.lang.String-

So far I'm not implementing a proper ReaderRIOT yet, just doing some
conversion to RDF.

On Wed, Aug 14, 2019 at 12:13 PM Andy Seaborne  wrote:
>
> StreamRDF is an interface called by parsers (and other things) based on
> what it sees.
>
> If in, say Turtle, teh pasrer sees a "BASE" then base(...) is called.
>
> StreamRDF (it is an interface) does not do anything - its a stream of
> incoming RDF for the implementation to deal with.
>
> StreamRDFLib.writer writes N-quads.  No way to say "BASE".
>
> Triples sent to triple() should be already resolved - a parser
> responsibility.
>
>  Andy
>
> On 14/08/2019 09:28, Claude Warren wrote:
> > The StreamRDF just passed the base() argument on to the sink so that the
> > sink would have the base in order to set create the FQ URI from local
> > URIs.
> >
> > StreamRDFLib simply ignores the base() call.
>
> Did you mean StreamRDFBase?
>
> StreamRDFLib is a colelction of fucntiosn and isn't itself does not have
> the StreamRDF interface.
>
> >  I assume this is because it
> > is intended to process fully qualified RDF.
> >
> > I think the assumption is that if you are streaming into the graph you
> > would need the base() to resolve any inbound local URIs while if you are
> > streaming out from the graph the URIs are already fully resolved.
> >
> > I didn't write this code so I am not certain but if that is the case
> > perhaps we should note it in the javadocs.
> >
> > I do note that StreamRDF says it is for output, in which case I am not
> > certain why the base() is needed at all.
> >
> > Claude
> >
> >
> >
> > On Tue, Aug 13, 2019 at 11:46 PM Martynas Jusevičius 
> > 
> > wrote:
> >
> >> Hi,
> >>
> >> I'm trying to understand what the purpose/usage of StreamRDF.base() is.
> >>
> >> Isn't it supposed to set the base URI that relative URIs in the stream
> >> resolve against?
> >>
> >> I've made a simple test:
> >>
> >>  StreamRDF rdfStream = StreamRDFLib.writer(new BufferedWriter(new
> >> OutputStreamWriter(System.out)));
> >>  rdfStream.start();
> >>  rdfStream.base("http://localhost/;);
> >>  rdfStream.triple(new Triple(NodeFactory.createBlankNode(),
> >> NodeFactory.createURI("relative"), NodeFactory.createBlankNode()));
> >>  rdfStream.finish();
> >>
> >> The output I get:
> >>
> >> _:Bf410fc50X2De0baX2D464eX2D996eX2Dbb3207090baa 
> >> _:B4b65b796X2D3561X2D4bf3X2Dbf31X2D1154aac0c816 .
> >>
> >> Why is the property URI  and not <http://localhost/relative>?
> >> Doesn't that make the output invalid N-Triples? Or am I writing it wrong?
> >>
> >> Martynas
> >> atomgraph.com
> >>
> >
> >

Re: StreamRDF.base()

[Andy Seaborne]

StreamRDF is an interface called by parsers (and other things) based on 
what it sees.


If in, say Turtle, teh pasrer sees a "BASE" then base(...) is called.

StreamRDF (it is an interface) does not do anything - its a stream of 
incoming RDF for the implementation to deal with.


StreamRDFLib.writer writes N-quads.  No way to say "BASE".

Triples sent to triple() should be already resolved - a parser 
responsibility.


Andy

On 14/08/2019 09:28, Claude Warren wrote:

The StreamRDF just passed the base() argument on to the sink so that the
sink would have the base in order to set create the FQ URI from local
URIs.

StreamRDFLib simply ignores the base() call.


Did you mean StreamRDFBase?

StreamRDFLib is a colelction of fucntiosn and isn't itself does not have 
the StreamRDF interface.



 I assume this is because it
is intended to process fully qualified RDF.

I think the assumption is that if you are streaming into the graph you
would need the base() to resolve any inbound local URIs while if you are
streaming out from the graph the URIs are already fully resolved.

I didn't write this code so I am not certain but if that is the case
perhaps we should note it in the javadocs.

I do note that StreamRDF says it is for output, in which case I am not
certain why the base() is needed at all.

Claude



On Tue, Aug 13, 2019 at 11:46 PM Martynas Jusevičius 
wrote:


Hi,

I'm trying to understand what the purpose/usage of StreamRDF.base() is.

Isn't it supposed to set the base URI that relative URIs in the stream
resolve against?

I've made a simple test:

 StreamRDF rdfStream = StreamRDFLib.writer(new BufferedWriter(new
OutputStreamWriter(System.out)));
 rdfStream.start();
 rdfStream.base("http://localhost/;);
 rdfStream.triple(new Triple(NodeFactory.createBlankNode(),
NodeFactory.createURI("relative"), NodeFactory.createBlankNode()));
 rdfStream.finish();

The output I get:

_:Bf410fc50X2De0baX2D464eX2D996eX2Dbb3207090baa 
_:B4b65b796X2D3561X2D4bf3X2Dbf31X2D1154aac0c816 .

Why is the property URI  and not <http://localhost/relative>?
Doesn't that make the output invalid N-Triples? Or am I writing it wrong?

Martynas
atomgraph.com

Re: StreamRDF.base()

[Claude Warren]

The StreamRDF just passed the base() argument on to the sink so that the
sink would have the base in order to set create the FQ URI from local
URIs.

StreamRDFLib simply ignores the base() call.  I assume this is because it
is intended to process fully qualified RDF.

I think the assumption is that if you are streaming into the graph you
would need the base() to resolve any inbound local URIs while if you are
streaming out from the graph the URIs are already fully resolved.

I didn't write this code so I am not certain but if that is the case
perhaps we should note it in the javadocs.

I do note that StreamRDF says it is for output, in which case I am not
certain why the base() is needed at all.

Claude



On Tue, Aug 13, 2019 at 11:46 PM Martynas Jusevičius 
wrote:

> Hi,
>
> I'm trying to understand what the purpose/usage of StreamRDF.base() is.
>
> Isn't it supposed to set the base URI that relative URIs in the stream
> resolve against?
>
> I've made a simple test:
>
> StreamRDF rdfStream = StreamRDFLib.writer(new BufferedWriter(new
> OutputStreamWriter(System.out)));
> rdfStream.start();
> rdfStream.base("http://localhost/;);
> rdfStream.triple(new Triple(NodeFactory.createBlankNode(),
> NodeFactory.createURI("relative"), NodeFactory.createBlankNode()));
> rdfStream.finish();
>
> The output I get:
>
> _:Bf410fc50X2De0baX2D464eX2D996eX2Dbb3207090baa 
> _:B4b65b796X2D3561X2D4bf3X2Dbf31X2D1154aac0c816 .
>
> Why is the property URI  and not <http://localhost/relative>?
> Doesn't that make the output invalid N-Triples? Or am I writing it wrong?
>
> Martynas
> atomgraph.com
>


-- 
I like: Like Like - The likeliest place on the web
<http://like-like.xenei.com>
LinkedIn: http://www.linkedin.com/in/claudewarren

StreamRDF.base()

[Martynas Jusevičius]

Hi,

I'm trying to understand what the purpose/usage of StreamRDF.base() is.

Isn't it supposed to set the base URI that relative URIs in the stream
resolve against?

I've made a simple test:

StreamRDF rdfStream = StreamRDFLib.writer(new BufferedWriter(new
OutputStreamWriter(System.out)));
rdfStream.start();
rdfStream.base("http://localhost/;);
rdfStream.triple(new Triple(NodeFactory.createBlankNode(),
NodeFactory.createURI("relative"), NodeFactory.createBlankNode()));
rdfStream.finish();

The output I get:

_:Bf410fc50X2De0baX2D464eX2D996eX2Dbb3207090baa 
_:B4b65b796X2D3561X2D4bf3X2Dbf31X2D1154aac0c816 .

Why is the property URI  and not <http://localhost/relative>?
Doesn't that make the output invalid N-Triples? Or am I writing it wrong?

Martynas
atomgraph.com