Just one thing to add re the autogeneration of a "default" content model assertion - we do currently do this for Fedora objects that don't have a RELS-EXT datastream or don't specify a content model in RELS-EXT. So maybe we should also remove this functionality?
> -----Original Message----- > From: aj...@virginia.edu [mailto:aj...@virginia.edu] > Sent: 29 October 2010 14:59 > To: Support and info exchange list for Fedora users. > Subject: Re: [fcrepo-user] Cmodel discovery? > > > My votes below. > > Another question: does the new Enhanced Content Model > functionality expect to find or rely on this triple? > > > (a) when ingesting content model objects, should we enforce > a RELS-EXT assertion to a valid content model for content > model objects? or > > Yes. _Any_ Fedora object should have a content model > discoverable through that same old hasModel relationship, and > that includes content models themselves. > > > (b) should we create a Resource Index triple identifying > the fedora-system:ContentModel-3.0 as a default for content > model objects when none is specified in RELS-EXT? > > No. The RI should reflect as closely as possible the actual > state of the objects, if for no other reason than so that > folks like Bill can turn up the kinds of things he just did > (which started this whole conversation). > > > (c) should we stop CMA features working (eg the > dissemination execution) if the object identified as the > content model does not itself identify through RELS-EXT that > it is a content model object? > > Yes. If the CM in question doesn't identify itself as a CM, > then the only way we know that it is one is when a > disseminator gets executed "through" it. (Or until any use of > Enhanced Content Model functionality that might turn up the > same fact.) That strikes me as unpleasantly "dynamic" for the > kinds of purposes Fedora meets. While that kind of > "duck-typing" in the repository could be very useful, it > could be very dangerous, and I suspect that most Fedora users > will more likely find it to be the latter. > > --- > A. Soroka > Digital Research and Scholarship R & D > the University of Virginia Library > > > > On Oct 28, 2010, at 11:11 AM, Steve Bayliss wrote: > > > Hi Bill > > > > Thanks for that - particularly confirming that > dissemination executions work even when the content model > object doesn't assert its own content model correctly. > > > > I wonder if we should add some kind of validation for this > - particularly as there could be an expectation that one > should be able to run these sorts of queries to determine > what content models exist. Or whether we we should (in a > similar manner to the "default" object content model) > behind-the-scenes create this triple identifying the default > content model for content model objects. > > > > So general questions for the list: > > > > (a) when ingesting content model objects, should we enforce > a RELS-EXT assertion to a valid content model for content > model objects? or > > (b) should we create a Resource Index triple identifying > the fedora-system:ContentModel-3.0 as a default for content > model objects when none is specified in RELS-EXT? > > (c) should we stop CMA features working (eg the > dissemination execution) if the object identified as the > content model does not itself identify through RELS-EXT that > it is a content model object? > > > > Or.... (d) do nothing! > > > > (I think there are probably issues at least with a and b - > how do we tell that an object is a content model object? > Surely the RELS-EXT assertion is the way to do that, but the > scenario is one where this assertion is not present.) > > > > Regards > > Steve > > -----Original Message----- > > From: Bill Parod [mailto:bill-pa...@northwestern.edu] > > Sent: 28 October 2010 15:56 > > To: Support and info exchange list for Fedora users. > > Subject: Re: [fcrepo-user] Cmodel discovery? > > > > Steve, > > > > On Oct 28, 2010, at 3:09 AM, Steve Bayliss wrote: > > > >> All Content Model objects *should* contain the triple that Adam has > >> identified, the triple isn't generated automatically > (however if an object > >> declares no content model, then a triple will be generated > identifying the > >> "default" content model - > info:fedora/fedora-system:FedoraObject-3.0). > >> > > > > Thanks very much for confirming the use of > <fedora-model:hasModel > rdf:resource="info:fedora/fedora-system:ContentModel-3.0"/> > as convention. > > > > Some of our cmodels do not assert it, so I will update them > to do so. > > > >> I'm not sure if the CMA works correctly if a Content Model > object fails to > >> declare that triple, perhaps that's what is going on in > this case? It would > >> be useful to confirm if (a) the RELS-EXT of the CModel > objects do indeed > >> fail to declare that triple and (b) if any objects > belonging to that CModel > >> "work" correctly wrt object methods etc. > >> > > > > Yes, they do work, at least as regards CMA binding for > dissemination execution. > > > >> If you want to query for content models *in use* by objects in the > >> repository, you could use the query > >> > >> select $o > >> from <#ri> > >> where $s <info:fedora/fedora-system:def/model#hasModel> $o > >> > >> and use the "Force Distinct" option in the risearch web > interface (or the > >> distinct=on query parameter if calling the risearch > service directly). > >> > > > > That's what I'm doing now, though since your confirmation > that cmodel objects should assert <fedora-model:hasModel > rdf:resource="info:fedora/fedora-system:ContentModel-3.0"/>, > I'll update all our cmodels to do so. I'm then inclined to > use Adam's original query suggestion as it seems more efficient: > > > > select $cmodel > > from <#ri> > > where $cmodel <fedora-model:hasModel> > "info:fedora/fedora-system:ContentModel-3.0" > > > > Thanks very much, > > > > - Bill > > > > > > > > > >> Steve > >> > >>> -----Original Message----- > >>> From: aj...@virginia.edu [mailto:aj...@virginia.edu] > >>> Sent: 22 October 2010 16:10 > >>> To: Support and info exchange list for Fedora users. > >>> Subject: Re: [fcrepo-user] Cmodel discovery? > >>> > >>> > >>> Bill-- > >>> > >>> Perhaps we're seeing CModels created by different means > >>> ending up with different RELS-EXT contents. I'm seeing that > >>> triple in all of our CModels, but because some of them were > >>> taken from external sources (e.g. a JPEG2000 CModel from the > >>> LANL Djatoka project) I don't know whether this triple is > >>> normatively produced or is just a matter of convention. > >>> > >>> Perhaps one of the Fedora developers can speak to this? > >>> > >>> --- > >>> A. Soroka > >>> Digital Research and Scholarship R & D > >>> the University of Virginia Library > >>> > >>> > >>> > >>> On Oct 22, 2010, at 10:59 AM, Bill Parod wrote: > >>> > >>>> Hi Adam, > >>>> > >>>> I tried it (with slightly different syntax): > >>>> select $cmodel > >>>> from <#ri> > >>>> where $cmodel <fedora-model:hasModel> > >>> <info:fedora/fedora-system:ContentModel-3.0> > >>>> > >>>> and found some of our cmodels but not all, which leads me > >>> to think that you've not only provided a query solution but > >>> revealed something some of our cmodels RELS-EXT are lacking: > >>>> > >>>> <fedora-model:hasModel > >>> rdf:resource="info:fedora/fedora-system:ContentModel-3.0"/> > >>>> > >>>> Is that indeed the convention? > >>>> > >>>> Thanks much! > >>>> > >>>> Bill > >>>> > >>>> > >>>> > >>>> > >>>> On Oct 22, 2010, at 9:40 AM, aj...@virginia.edu wrote: > >>>> > >>>>> Bill-- > >>>>> > >>>>> If I'm not mistaken, you'll find an RDF statement: > >>>>> > >>>>> <fedora-model:hasModel > >>> rdf:resource="info:fedora/fedora-system:ContentModel-3.0"/> > >>>>> > >>>>> in every cModel object. Might that be a query that can do > >>> the job? Something like: > >>>>> > >>>>> select $cmodel > >>>>> from <#ri> > >>>>> where $cmodel <fedora-model:hasModel> > >>> "info:fedora/fedora-system:ContentModel-3.0" > >>>>> > >>>>> > >>>>> --- > >>>>> A. Soroka > >>>>> Digital Research and Scholarship R & D > >>>>> the University of Virginia Library > >>>>> > >>>>> > >>>>> > >>>>> On Oct 22, 2010, at 10:34 AM, Bill Parod wrote: > >>>>> > >>>>>> I'm working on a repository introspection service that > >>> provides a repository profile from the point of view of > >>> cmodels and services. The motivation is to obtain a concise > >>> picture of what's in the repository, provide export tools to > >>> aid in selective migration, and to generate model/service > >>> documentation from the models and services themselves. > >>>>>> > >>>>>> My question is this: Is there a way, using Fedora REST > >>> APIs or triple store queries to obtain a list of the pids of > >>> cmodel objects in the repository? > >>>>>> > >>>>>> I'm currently using the triple store to query for cmodel > >>> / service pairings: > >>>>>> select $cmodel $service > >>>>>> from <#ri> > >>>>>> where $cmodel <fedora-model:hasService> $service > >>>>>> > >>>>>> But that will only find cmodels that have associated > >>> services. Ours tend to fall into that category but I'd like > >>> to do it in a way that is more general. I'm not very > >>> experienced with using the tripe store, so I'm hoping there's > >>> a way there to do this, though that seems doubtful from what > >>> I'm seeing in cmodel RELS-EXT. > >>>>>> > >>>>>> I know I can do a sql query on the database ( select > >>> distinct cModel from modelDeploymentMap) , but I'd of course > >>> like to avoid cutting in at that level, and I'm not sure > >>> cmodels without services are represented there anyway. > >>>>>> > >>>>>> Is there a way to discover cmodels using the APIs or the > >>> triple store? Or is it best to put something specific in > >>> cmodel RELS-EXT for that purpose? That's what I'm about to > >>> do, but thought I'd ask first. > >>>>>> > >>>>>> Thanks, > >>>>>> Bill > >>>>>> > >>>>>> Bill Parod > >>>>>> Library Technology Division - Enterprise Systems > >>>>>> Northwestern University Library > >>>>>> bill-pa...@northwestern.edu > >>>>>> 847 491 5368 > >>>>>> > >>>>>> > >>>>>> > >>>>>> > >>>>>> > >>> -------------------------------------------------------------- > >>> ---------------- > >>>>>> Nokia and AT&T present the 2010 Calling All > >>> Innovators-North America contest > >>>>>> Create new apps & games for the Nokia N8 for consumers in > >>> U.S. and Canada > >>>>>> $10 million total in prizes - $4M cash, 500 devices, > >>> nearly $6M in marketing > >>>>>> Develop with Nokia Qt SDK, Web Runtime, or Java and > >>> Publish to Ovi Store > >>>>>> > >>> http://p.sf.net/sfu/nokia-dev2dev_____________________________ > >>> __________________ > >>>>>> Fedora-commons-users mailing list > >>>>>> Fedora-commons-users@lists.sourceforge.net > >>>>>> > https://lists.sourceforge.net/lists/listinfo/fedora-commons-users > >>>>> > >>>>> > >>>>> > >>> -------------------------------------------------------------- > >>> ---------------- > >>>>> Nokia and AT&T present the 2010 Calling All > >>> Innovators-North America contest > >>>>> Create new apps & games for the Nokia N8 for consumers in > >>> U.S. and Canada > >>>>> $10 million total in prizes - $4M cash, 500 devices, > >>> nearly $6M in marketing > >>>>> Develop with Nokia Qt SDK, Web Runtime, or Java and > >>> Publish to Ovi Store > >>>>> http://p.sf.net/sfu/nokia-dev2dev > >>>>> _______________________________________________ > >>>>> Fedora-commons-users mailing list > >>>>> Fedora-commons-users@lists.sourceforge.net > >>>>> > https://lists.sourceforge.net/lists/listinfo/fedora-commons-users > >>>> > >>>> Bill Parod > >>>> Library Technology Division - Enterprise Systems > >>>> Northwestern University Library > >>>> bill-pa...@northwestern.edu > >>>> 847 491 5368 > >>>> > >>>> > >>>> > >>>> > >>>> > >>> -------------------------------------------------------------- > >>> ---------------- > >>>> Nokia and AT&T present the 2010 Calling All > >>> Innovators-North America contest > >>>> Create new apps & games for the Nokia N8 for consumers in > >>> U.S. and Canada > >>>> $10 million total in prizes - $4M cash, 500 devices, nearly > >>> $6M in marketing > >>>> Develop with Nokia Qt SDK, Web Runtime, or Java and Publish > >>> to Ovi Store > >>>> > >>> http://p.sf.net/sfu/nokia-dev2dev_____________________________ > >> __________________ > >>> Fedora-commons-users mailing list > >>> Fedora-commons-users@lists.sourceforge.net > >>> https://lists.sourceforge.net/lists/listinfo/fedora-commons-users > >> > >> > >> > -------------------------------------------------------------- > -------------- > >> -- > >> Nokia and AT&T present the 2010 Calling All > Innovators-North America contest > >> Create new apps & games for the Nokia N8 for consumers in > U.S. and Canada > >> $10 million total in prizes - $4M cash, 500 devices, > nearly $6M in marketing > >> Develop with Nokia Qt SDK, Web Runtime, or Java and > Publish to Ovi Store > >> http://p.sf.net/sfu/nokia-dev2dev > >> _______________________________________________ > >> Fedora-commons-users mailing list > >> Fedora-commons-users@lists.sourceforge.net > >> https://lists.sourceforge.net/lists/listinfo/fedora-commons-users > >> > >> > >> > -------------------------------------------------------------- > ---------------- > >> Nokia and AT&T present the 2010 Calling All > Innovators-North America contest > >> Create new apps & games for the Nokia N8 for consumers in > U.S. and Canada > >> $10 million total in prizes - $4M cash, 500 devices, > nearly $6M in marketing > >> Develop with Nokia Qt SDK, Web Runtime, or Java and > Publish to Ovi Store > >> http://p.sf.net/sfu/nokia-dev2dev > >> _______________________________________________ > >> Fedora-commons-users mailing list > >> Fedora-commons-users@lists.sourceforge.net > >> https://lists.sourceforge.net/lists/listinfo/fedora-commons-users > > > > Bill Parod > > Library Technology Division - Enterprise Systems > > Northwestern University Library > > bill-pa...@northwestern.edu > > 847 491 5368 > > > > > > > > > > > -------------------------------------------------------------- > ---------------- > > Nokia and AT&T present the 2010 Calling All > Innovators-North America contest > > Create new apps & games for the Nokia N8 for consumers in > U.S. and Canada > > $10 million total in prizes - $4M cash, 500 devices, nearly > $6M in marketing > > Develop with Nokia Qt SDK, Web Runtime, or Java and Publish > to Ovi Store > > > http://p.sf.net/sfu/nokia-dev2dev_____________________________ __________________ > Fedora-commons-users mailing list > Fedora-commons-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/fedora-commons-users ---------------------------------------------------------------------------- -- Nokia and AT&T present the 2010 Calling All Innovators-North America contest Create new apps & games for the Nokia N8 for consumers in U.S. and Canada $10 million total in prizes - $4M cash, 500 devices, nearly $6M in marketing Develop with Nokia Qt SDK, Web Runtime, or Java and Publish to Ovi Store http://p.sf.net/sfu/nokia-dev2dev _______________________________________________ Fedora-commons-users mailing list Fedora-commons-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/fedora-commons-users ------------------------------------------------------------------------------ Nokia and AT&T present the 2010 Calling All Innovators-North America contest Create new apps & games for the Nokia N8 for consumers in U.S. and Canada $10 million total in prizes - $4M cash, 500 devices, nearly $6M in marketing Develop with Nokia Qt SDK, Web Runtime, or Java and Publish to Ovi Store http://p.sf.net/sfu/nokia-dev2dev _______________________________________________ Fedora-commons-users mailing list Fedora-commons-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/fedora-commons-users
