The Many Shapes of SHACL Transcript - Revision history

Marco: /* Question and Answer Session */

2025-11-17T18:48:15Z

Question and Answer Session

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 Thank you very much that's quite exciting a lot of stuff a lot of good stuff that I see here I had another question from Dean Allemang he wants to know is there a free solution available that can be used for SHACL authoring well so obviously
-top right the current iteration of top right is a commercial product so from from our side there is at the moment no free solution other than the old TopBraid composer the free edition that weused to have but that's now no longer really maintained and no longer recommended and yeah I can't speak about other tools I'm not familiar with other tools that would be free and that would do similar things for tracking authoring Andreas Esser is there also a way to define the severity strict violation warning of syntax constraints for example type like for semantic constraints so the severity of like shades yes yes absolutely yes so um I think I had done that with the ISO code here so it's possible to set the severity to three levels one of them is the default which is basically how's it called violation and then there is info and warning yeah and you can specify this either on the shape levels and then it will apply to all the constraints in the shape or it will be defined for individual
+top right the current iteration of top right is a commercial product so from from our side there is at the moment no free solution other than the old TopBraid Composer the free edition that weused to have but that's now no longer really maintained and no longer recommended and yeah I can't speak about other tools I'm not familiar with other tools that would be free and that would do similar things for tracking authoring Andreas Esser is there also a way to define the severity strict violation warning of syntax constraints for example type like for semantic constraints so the severity of like shades yes yes absolutely yes so um I think I had done that with the ISO code here so it's possible to set the severity to three levels one of them is the default which is basically how's it called violation and then there is info and warning yeah and you can specify this either on the shape levels and then it will apply to all the constraints in the shape or it will be defined for individual
 properties as well individual constraints as well yeah like this yes my question was more like is it possible to use the severity feature also for stuff like cardinality or for the type yes you can do this everywhere yes because one of the more constraints okay for all of them yes each other I don't have those okay thank you thank you for the question we have another one from Ludger Rinsche, when you convert an OLW ontology into SHACL you get the problem many our rules are not imported for validation for example you don't want that all country entities have to be off the type scores concept is there an easy solution to manage the ontology and the corresponding SHACL shapes for validation from a single code base yeah
 again not sure if I understand the question so what we have done is
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 this and vise versa yeah not sure if that person wants to
 add to your question
-no seems to be satisfied sorry no I had
+no seems to be satisfied sorry no I had yes the problem is if you you started creating the on Tomo and ontology with the fact that all cities are subclass of course concept right and if and that's right for the ontology but that doesn't mean that an instance of our city should be as course concept and if you use the same same checker rules to validate them then at least I feel like you have a problem with with this but maybe it it's not a problem if you do it within your
-yes the problem is if you you started
+tool but if you take an ontology that says this class has to be concept and then you derive the shekel constraints from that there will be a constraint that says every city has to be a concept yeah well but but that is simply a class
-creating the on Tomo and ontology with the fact that all cities are subclass of
+inheritance so it is defined by subclass off and the semantics of that are not very different from our semantics in my opinion basically every instance of city will also be an instance of Scots concept automatically and that is I
-course concept right and if and that's
+think how normal rdf schema semantics and all that behaves so i'm not seeing the problem yet ok ok we have another question here from dinner table daria open spells correctiy pronounces correctly are there validation and inference engines that are built into composer for validating our SHACL ontologies yeah sure composer does have validation view and also inference button so basically there is a panel where you can run the whole constraint violation report and also on the form entry composer will have has a mode where you can basically reject invalid data and you can can press an inferencing button to see all the rules firing and it has a value rules as well that I've shown okay another question from Veronica I'm stuck is it possible to express a mathematical expression with SHACL like for every third element X eg person there shall be at least one of object weg chair here one must use the total number of elements to decide if the resource contains enough of the certain object conditionality I would say is that part of your oh yeah yeah no III I understand that question it's the same that we observed well there is a limit to everything there's a limit to all those declarative languages there's a limit to SPARQL there's a limit to what we have come up with there was no expressions in SHACL they only take you you know that far so at some stage you need something richer and that is pretty much exactly why we added those scripts recently because they allow you to do really arbitrary things arbitrary calculations and yeah there you're not limited to anything and you can then use those as I couldn't show that but basically you can use those expressions also as inference if you like if you want them as triples actually want the results as a triple okay Veronika would you like to add to this questions no it was the answer I was hoping for thank you very much very good. Greg Trzeciak Fresnel has Fresnel purpose property for its lenses for example summary details is there any equivalent for Node shapes okay okay those who don't remember Fresnel it's it was one of the I think it's called "frɛnɛl" actually it was a similar attempt to what we have done in tracking with property groups and water and so on to define inform layouts and well you have seen the properties that are there if anything is missing just add another property you it's an RDF so and given that it's an RDF it's an open data model you can attach any other information to your shape definitions and do whatever you like so the answer is not directly built in but easy to add okay naveen does the javascript declared variable get persisted to be used
-right for the ontology but that doesn't mean that an instance of our city should
+elsewhere for example in GraphQL so yeah so look my demo was very broken it wasn't didn't have enough time really
 and then they had this glitch yeah so but yeah all these technologies fit
 together that they work together so if you have defined your inference in

Marco: /* Questions and Answers */

2025-11-17T18:38:59Z

Questions and Answers

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	right so I think that was everything I wanted to show and I really appreciate your patience and yeah passing back to Marco thank you thank you very much		right so I think that was everything I wanted to show and I really appreciate your patience and yeah passing back to Marco thank you thank you very much

	===~~Questions~~ and ~~Answers~~===		===Question and Answer Session===

	Thank you very much that's quite exciting a lot of stuff a lot of good stuff that I see here I had another question from Dean Allemang he wants to know is there a free solution available that can be used for SHACL authoring well so obviously		Thank you very much that's quite exciting a lot of stuff a lot of good stuff that I see here I had another question from Dean Allemang he wants to know is there a free solution available that can be used for SHACL authoring well so obviously

Marco at 18:37, 17 November 2025

2025-11-17T18:37:35Z

← Older revision		Revision as of 18:37, 17 November 2025
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	here just like the colors here are also inferred using message values and the		here just like the colors here are also inferred using message values and the
	number and the fact that this rectangle shows up at all is also inferred so it		number and the fact that this rectangle shows up at all is also inferred so it
	is a bit of shadow magic happening in		is a bit of shadow magic happening in the background here yeah.
	the background here yeah ~~so BlueTEC players~~ turn he gets a few more armies to drop and so on so I'm I'm not going
	to finish this whole game just to show that it's an alternative way of if you like data		So blue player's turn he gets a few more armies to drop and so on so I'm I'm not going to finish this whole game just to show that it's an alternative way of if you like data entry to use a map as an interface yeah so for geographical applications this might actually have real use cases but when you click on something it could then add the territory or whatever you have clicked on to some data structure on in your RDF data model and so on all
	entry to use a map as an interface yeah so for geographical applications this		right so I think that was everything I wanted to show and I really appreciate your patience and yeah passing back to Marco thank you thank you very much
	might actually have real use cases but when you click on something it could then add the territory or whatever you
	have clicked on to some data structure on in your RDF data model and so on all		===Questions and Answers===
	right so I think that was everything I wanted to show and I really appreciate
	your patience and yeah passing back to ~~mark oh~~ thank you thank you very much		Thank you very much that's quite exciting a lot of stuff a lot of good stuff that I see here I had another question from Dean Allemang he wants to know is there a free solution available that can be used for SHACL authoring well so obviously
	Questions and Answers		top right the current iteration of top right is a commercial product so from from our side there is at the moment no free solution other than the old TopBraid composer the free edition that weused to have but that's now no longer really maintained and no longer recommended and yeah I can't speak about other tools I'm not familiar with other tools that would be free and that would do similar things for tracking authoring Andreas Esser is there also a way to define the severity strict violation warning of syntax constraints for example type like for semantic constraints so the severity of like shades yes yes absolutely yes so um I think I had done that with the ISO code here so it's possible to set the severity to three levels one of them is the default which is basically how's it called violation and then there is info and warning yeah and you can specify this either on the shape levels and then it will apply to all the constraints in the shape or it will be defined for individual
	~~for Graham~~ that~~'s it~~'s quite exciting a lot of stuff a lot of good stuff that I		properties as well individual constraints as well yeah like this yes my question was more like is it possible to use the severity feature also for stuff like cardinality or for the type yes you can do this everywhere yes because one of the more constraints okay for all of them yes each other I don't have those okay thank you thank you for the question we have another one from Ludger Rinsche, when you convert an OLW ontology into SHACL you get the problem many our rules are not imported for validation for example you don't want that all country entities have to be off the type scores concept is there an easy solution to manage the ontology and the corresponding SHACL shapes for validation from a single code base yeah
	see here I had another question from Dean ~~Aleman~~ he wants to know is there a
	free solution available that can be used for SHACL authoring well so obviously
	top right the current iteration of top right is a commercial product so from
	from our side there is at the moment no free solution other than the old ~~top right~~ composer the free edition that we
	~~used~~ to have but that's now no longer really maintained and no longer recommended and yeah I can't speak about
	other tools I'm not familiar with other tools that would be free and that would do similar things for tracking authoring
	~~Andria's~~ Esser is there also a way to define the severity strict violation
	warning of syntax constraints for example type like for semantic
	constraints so the severity of like shades yes yes
	absolutely yes so um I think I had done that with the ISO code here so it's
	possible to set the severity to three levels one of them is the default which
	is basically how's it called violation
	and then there is info and warning yeah and you can specify this either on the shape levels and then it will apply to
	all the constraints in the shape or it will be defined for individual
	properties as well individual constraints as well yeah like this yes my question was more like is it
	possible to use the severity feature also for stuff like cardinality or for
	the type yes you can do this everywhere yes because one of the more constraints
	okay for all of them yes each other I don't have those okay thank you thank you for the question
	we have another one from ~~latke Ranger~~ when you convert an ~~owl~~ ontology into
	SHACL you get the problem many our rules are not imported for validation for example you don't want that all
	country entities have to be off the type scores concept is there an easy solution
	to manage the ontology and the corresponding SHACL shapes for validation from a single code base yeah
	again not sure if I understand the question so what we have done is		again not sure if I understand the question so what we have done is
	basically that he allows you to to use owl and SHACL at the same time for their specific strengths and tasks and		basically that he allows you to to use owl and SHACL at the same time for their specific strengths and tasks and

Marco at 18:14, 17 November 2025

2025-11-17T18:14:37Z

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Marco at 16:39, 17 November 2025

2025-11-17T16:39:25Z

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Marco at 15:49, 17 November 2025

2025-11-17T15:49:42Z

← Older revision		Revision as of 15:49, 17 November 2025
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	When I was thinking about how to introduce SHACL there are various ways in which you could do that and some people prefer to learn a new language by looking at the manuals are looking at the specifications even that is one approach so if you go to the official main document for SHACL which is this one here you can theoretically try to learn SHACL from this. But I don't think that's a good idea it's formal specification it means it is written for more for computers and for implementers than for users. So if you try to come this way you will be confronted with terms like well Focus Nodes, Target Node and Node Shapes and Shapes Graph and all these terms will be new and you'll be probably not really understand what they mean in the first round so what I'm trying to do in that and my preferred way of talking about SHACL is to connect it to something that people already know and already familiar with and I guess everyone at least in this audience should be familiar with concepts like classes, instances and properties. So that's where I'm going to start as a way of explaining SHACL, the basic ideas and then I'm moving forwards explaining well what can SHACL do what other approaches can not do as well. I hope I can get across that SHACL is no rocket science, in particular if you have reasonable tools that help you with the job.		When I was thinking about how to introduce SHACL there are various ways in which you could do that and some people prefer to learn a new language by looking at the manuals are looking at the specifications even that is one approach so if you go to the official main document for SHACL which is this one here you can theoretically try to learn SHACL from this. But I don't think that's a good idea it's formal specification it means it is written for more for computers and for implementers than for users. So if you try to come this way you will be confronted with terms like well Focus Nodes, Target Node and Node Shapes and Shapes Graph and all these terms will be new and you'll be probably not really understand what they mean in the first round so what I'm trying to do in that and my preferred way of talking about SHACL is to connect it to something that people already know and already familiar with and I guess everyone at least in this audience should be familiar with concepts like classes, instances and properties. So that's where I'm going to start as a way of explaining SHACL, the basic ideas and then I'm moving forwards explaining well what can SHACL do what other approaches can not do as well. I hope I can get across that SHACL is no rocket science, in particular if you have reasonable tools that help you with the job.

	Speaking about tools, I'm going to show obvsiouly as a person who has been developing such tools and in the last many years I'm going to show one of those tools that we have built and that we are using using for SHACL development as well called TopBraid EDG if anyone is interested in also using this this tool can be downloaded for free basically what you need to do is you need to download TopBraid Composer which for which there is a free evaluation period of a month or so once you have downloaded this you will find a small button here called TopBraid Applications open TopBraid EDG and then basically this is opening this in your Web Browser because TopBraid EDG in principle is a web-based tool it's not a desktop tool yeah so that's how you would end up with this and which is also my starting point for what I'm trying to show so I'd like to use this now to build a small ontology in SHACL and along the way explain a few things and for those who are already very familiar with SHACL apologies I know this will be recorded so many people may also come across this presentation so I'm trying to get everyone or keep everyone on board ~~all~~ right let's create something so um I'm creating in this TopBraid EDG user interface I am creating a small ontology and we are using the term ontology here in the sense of a data model for for some you know for classes properties and instances and there there are many ways of defining ontology some people are just using RDFS Schema others are using OWL we have moved to SHACL for that job so we have kept the term ontology for that and I'll just create a small ontology called TheOnt, just so that you have a small name as a prefix as well so and this ontology is going to build on top of SKOS, so I'm just to get started I'm including a smallest SKOS ontology which is also written in SHACL just to have something as a foundation alright so now this is the TopBriad EDG ontology editor now this is the main screen that we will be in for the next couple of minutes and consists of multiple panels here like we have the class hierarchy here we have main form view here in the center we have another view down here and if you click on a class you get to see the details of the class definition and the properties that it has defined and other stuff so this is not just a normal class in the sense of say an OWL class, it is in fact an OWL class here this is this SKOS Concept class it's also a Node Shape and this is a term from SHACL it's and this is kind of you can think of Node Shape as a type of a ~~class~~ it's similar to a class because it also defines a collection of properties that typically belong together to describe an object yeah and in the case of SKOS ~~concept~~ there are already lots of properties defined and you can see here them here like the preferred label and broader narrower and so on they are all here.		Speaking about tools, I'm going to show obvsiouly as a person who has been developing such tools and in the last many years I'm going to show one of those tools that we have built and that we are using using for SHACL development as well called TopBraid EDG if anyone is interested in also using this this tool can be downloaded for free basically what you need to do is you need to download TopBraid Composer which for which there is a free evaluation period of a month or so once you have downloaded this you will find a small button here called TopBraid Applications open TopBraid EDG and then basically this is opening this in your Web Browser because TopBraid EDG in principle is a web-based tool it's not a desktop tool yeah so that's how you would end up with this and which is also my starting point for what I'm trying to show so I'd like to use this now to build a small ontology in SHACL and along the way explain a few things and for those who are already very familiar with SHACL apologies I know this will be recorded so many people may also come across this presentation so I'm trying to get everyone or keep everyone on board.

			All right let's create something so um I'm creating in this TopBraid EDG user interface I am creating a small ontology and we are using the term ontology here in the sense of a data model for for some, you know for classes, properties and instances and there there are many ways of defining ontology some people are just using RDFS Schema others are using OWL we have moved to SHACL for that job. So we have kept the term ontology for that and I'll just create a small ontology called TheOnt, just so that you have a small name as a prefix as well so and this ontology is going to build on top of SKOS, so I'm just to get started I'm including a smallest SKOS ontology which is also written in SHACL just to have something as a foundation alright so now this is the TopBriad EDG ontology editor now this is the main screen that we will be in for the next couple of minutes and consists of multiple panels here like we have the class hierarchy here we have main form view here in the center we have another view down here and if you click on a class you get to see the details of the class definition and the properties that it has defined and other stuff. So this is not just a normal class in the sense of say an OWL class, it is in fact an OWL class here this is this SKOS Concept class it's also a Node Shape and this is a term from SHACL it's and this is kind of you can think of Node Shape as a type of a Class, it's similar to a class because it also defines a collection of properties that typically belong together to describe an object yeah and in the case of SKOS Concept there are already lots of properties defined and you can see here them here like the preferred label and broader, narrower and so on they are all here.

	So I can now start creating some additional classes and as I'm using the user interface I'm also going to show you the source code that is behind what		So I can now start creating some additional classes and as I'm using the user interface I'm also going to show you the source code that is behind what
	I'm doing so it's not just the graphics okay so let's create a very small ontology with just two classes to keep it simple and so that we can get along with the time that limited time that we have so let's create a class ~~city~~ and every dialogue here and ~~top right~~ has a preview button that allows you to see the triples that are being created and I must assume that you all understand ~~turtle~~ a little bit at least that you can read this what this means so when		I'm doing so it's not just the graphics okay so let's create a very small ontology with just two classes to keep it simple and so that we can get along with the time that limited time that we have so let's create a class City and every dialogue here and TopBraid has a preview button that allows you to see the triples that are being created and I must assume that you all understand Turtle a little bit at least that you can read this what this means so when
	you're creating a ~~class~~ the class will be both the ~~class~~ and a ~~note~~ shape and well in this case I've created a sub class of ~~scores~~ concept so let's do this		you're creating a Class the class will be both the Class and a Node shape and well in this case I've created a sub class of SKOS concept so let's do this
	now if you find a class City and let's say we want for every ~~city~~ we want to store say the number of inhabitants so the population so to do that well click		now if you find a class City and let's say we want for every City we want to store say the number of inhabitants, so the population so to do that well click here create attribute and in this dialogue then I can say what is my property doing so it's called population and well I could add a description not necessary I would say it's optional it doesn't have to be specified and the data type is Integer okay and typically it should be a positive value at least not negative. Yeah so this is now a dialogue to create what's called a property shape and if you look at the preview this basically means that the Node shape is going to point at a PropertyShape so there's a property or that it's called sh:property which links the Node shape that I've just created the city Node shape with the property definition and the property definition then is an instance of property shape which typically or should have a name which is for display purposes and then it has a number of constraints but most importantly it must have a sh:path and the path is basically specifying the RDF property or SHACL 1.1 path expression as SPARQL 1.1 it was path expression too if it's more complicating for example for inverse directions and so on.
	here create attribute and in this dialogue then I can say ~~well what~~ what is my property doing so it's called population and well I could add a description not necessary I would say it's optional it doesn't have to be specified and the data type is ~~integer~~ okay and typically it should be a positive value at least not negative ~~yeah~~ so this is now a dialogue to create what's called a property shape and if you look at the preview this basically means that the ~~node~~ shape is going to point at a ~~property shape~~ so there's a property or that it's called Sh property which links the ~~node~~ shape that I've just created the city ~~node~~ shape with the property definition and the property definition then is an instance of property shape which typically or should have a name which is for display purposes and then it has a number of constraints but most importantly it must have a path and the
	path is basically specifying the RDF property or SHACL 1.1 path expression
	as SPARQL 1.1 it was path expression too if it's more complicating for example
	for inverse directions and so on.

	Alright so let's create this population and it doesn't really have much else to do for now it's just an integer let's create a second class. Let's call it country and we want to model something that country is a collection of cities or that they in terms of the SKOS hierarchy that the cities are children of a country now fairly simple use case so that's another class which is also no		Alright so let's create this population and it doesn't really have much else to do for now it's just an integer let's create a second class. Let's call it country and we want to model something that country is a collection of cities or that they in terms of the SKOS hierarchy that the cities are children of a country now fairly simple use case so that's another class which is also no

Marco at 14:24, 17 November 2025

2025-11-17T14:24:15Z

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	Thanks [[Marco Neumann\|Marco]] for the invite and for having the pleasure to present to you all today. When we originally set this up or talked about this we wanted to make this a rather advanced or futuristic talk about where should SHACL go. As it turned out from the first rounds of feedback there were lots of newcomers still so I'm trying to find a balance between some advanced stuff and still trying to also give an introduction to SHACL for those who have never really used it.		Thanks [[Marco Neumann\|Marco]] for the invite and for having the pleasure to present to you all today. When we originally set this up or talked about this we wanted to make this a rather advanced or futuristic talk about where should SHACL go. As it turned out from the first rounds of feedback there were lots of newcomers still so I'm trying to find a balance between some advanced stuff and still trying to also give an introduction to SHACL for those who have never really used it.

	So, I have exactly three slides of PowerPoint and the first one is just the title, the second one is the overview, so what am i planning to show in this hour roughly so first I'm walking through a couple of examples of building things in SHACL and along the way try to explain some of the main ideas of SHACL then I'll show how SHACL can be used in practice for example for creating ~~user interfaces~~ like form editors and search and so on this will also include some part of talking about validation, then I moved to inference rules which is a technique to create new facts out of existing facts then I'll show some generative features where SHACL used to drive JSON integration through GraphQL and then in the end I have something new to show which will hopefully be interesting to some people. Alright so let's get started so um I was preparing for this by trying to find a list of implementations that now exist of SHACL and I found rather encouraging so because SHACL hasn't been around for that long has become a standard just three years ago and the first one and a half years or so it was a rather slow start but now we have fairly a long list of existing implementations out there and in particular basically every platform in the world is now covered so we have you know there's dotNet implementation there's one a couple of of Java based implementations there is one for Python, one in JavaScript at least one and so and so on and and all the the usual suspects the big triple store vendors are also on board and even the company that is not even using our RDF their main graph language, even ~~Neo4j~~ has now started to use SHACL and support SHACL so it seems to have arrived in the market and it's hopefully not going away anytime soon. All right, so...		So, I have exactly three slides of PowerPoint and the first one is just the title, the second one is the overview, so what am I planning to show in this hour roughly so first I'm walking through a couple of examples of building things in SHACL and along the way try to explain some of the main ideas of SHACL then I'll show how SHACL can be used in practice for example for creating User Interfaces like form editors and search and so on, this will also include some part of talking about validation, then I moved to inference rules which is a technique to create new facts out of existing facts then I'll show some generative features where is SHACL used to drive JSON integration through GraphQL and then in the end I have something new to show which will hopefully be interesting to some people.

			Alright so let's get started, so um I was preparing for this by trying to find a list of implementations that now exist of SHACL and I found rather encouraging so because SHACL hasn't been around for that long has become a standard just three years ago and the first one and a half years or so it was a rather slow start but now we have a fairly a long list of existing implementations out there and in particular basically every platform in the world is now covered so we have you know there's dotNet implementation there's one a couple of of Java based implementations there is one for Python, one in JavaScript at least one and so and so on and and all the the usual suspects the big triple store vendors are also on board and even the company that is not even using our RDF their main graph language, even Neo4J has now started to use SHACL and support SHACL so it seems to have arrived in the market and it's hopefully not going away anytime soon. All right, so...

	SHACL Quick Start and Overview		SHACL Quick Start and Overview

	When I was thinking about how to introduce SHACL there are various ways in which you could do that and some people prefer to learn a new language by looking at the manuals are looking at		When I was thinking about how to introduce SHACL there are various ways in which you could do that and some people prefer to learn a new language by looking at the manuals are looking at the specifications even that is one approach so if you go to the official main document for SHACL which is this one here you can theoretically try to learn SHACL from this. But I don't think that's a good idea it's formal specification it means it is written for more for computers and for implementers than for users. So if you try to come this way you will be confronted with terms like well Focus Nodes, Target Node and Node Shapes and Shapes Graph and all these terms will be new and you'll be probably not really understand what they mean in the first round so what I'm trying to do in that and my preferred way of talking about SHACL is to connect it to something that people already know and already familiar with and I guess everyone at least in this audience should be familiar with concepts like classes, instances and properties. So that's where I'm going to start as a way of explaining SHACL, the basic ideas and then I'm moving forwards explaining well what can SHACL do what other approaches can not do as well. I hope I can get across that SHACL is no rocket science, in particular if you have reasonable tools that help you with the job.
	the specifications even that is one approach so if you go to the official main document for SHACL which is this one ~~yeah~~ you can theoretically try to learn SHACL from this ~~but~~ I don't think that's a good idea it's formal specification it means it is written for more for computers and for implementers than for users. So if you try to come this way you will be confronted with terms like well Focus Nodes, Target Node and Node Shapes and Shapes Graph and all these terms will be new and you'll be probably not really understand what they mean in the first round so what I'm trying to do in that and my preferred way of talking about SHACL is to connect it to something that people already know and already familiar with and I guess everyone at least in this audience should be familiar with concepts like classes, instances and properties. So that's where I'm going to start as a way of explaining SHACL, the basic ideas and then I'm moving forwards explaining well what can SHACL do what other approaches can not do as well. I hope I can get across that SHACL is ~~not~~ rocket science, in particular if you have reasonable tools that help you with the job.

	Speaking about tools I'm going to show obvsiouly as a person who has been developing such tools and in the last many years I'm going to show one of those tools that we have built and that we are using using for SHACL development as well called TopBraid EDG if anyone is interested in also using this this tool can be downloaded for free basically what you need to do is you need to download ~~top right composer~~ which for which there is a free evaluation period of a month or so once you have downloaded this you will find a small button here called TopBraid Applications open TopBraid EDG and then basically this is opening this in your ~~web browser~~ because TopBraid EDG in principle is a web-based tool it's not a desktop tool yeah so that's how you would end up with this and which is also my starting point for what I'm trying to show so I'd like to use this now to build a small ontology in SHACL and along the way explain a few things and for those who are already very familiar with SHACL apologies I know this will be recorded so many people may also come across this presentation so I'm trying to get everyone or keep everyone on board all right let's create something so um I'm creating in this TopBraid EDG user interface I am creating a small ontology and we are using the term ontology here in the sense of a data model for for some you know for classes properties and instances and there there are many ways of defining ontology some people are just using RDFS Schema others are using ~~owl~~ we have moved to SHACL for that job so we have kept the term ontology for that and I'll just create a small ontology called TheOnt, just so that you have a small name as a prefix as well so and this ontology is going to build on top of SKOS, so I'm just to get started I'm including a smallest SKOS ontology which is also written in SHACL just to have something as a foundation alright so now this is the ~~ToopBriad~~ EDG ontology editor now this is the main screen that we will be in for the next couple of minutes and consists of multiple panels here like we have the class hierarchy here we have main form view here in the center we have another view down here and if you click on a class you get to see the details of the class definition and the properties that it has defined and other stuff so this is not just a normal class in the sense of say an OWL class, it is in fact an OWL class here this is this SKOS Concept class it's also a Node Shape and this is a term from SHACL it's and this is kind of you can think of Node Shape as a type of a class it's similar to a class because it also defines a collection of properties that typically belong together to describe an object yeah and in the case of SKOS concept there are already lots of properties defined and you can see here them here like the preferred label and broader narrower and so on they are all here.		Speaking about tools, I'm going to show obvsiouly as a person who has been developing such tools and in the last many years I'm going to show one of those tools that we have built and that we are using using for SHACL development as well called TopBraid EDG if anyone is interested in also using this this tool can be downloaded for free basically what you need to do is you need to download TopBraid Composer which for which there is a free evaluation period of a month or so once you have downloaded this you will find a small button here called TopBraid Applications open TopBraid EDG and then basically this is opening this in your Web Browser because TopBraid EDG in principle is a web-based tool it's not a desktop tool yeah so that's how you would end up with this and which is also my starting point for what I'm trying to show so I'd like to use this now to build a small ontology in SHACL and along the way explain a few things and for those who are already very familiar with SHACL apologies I know this will be recorded so many people may also come across this presentation so I'm trying to get everyone or keep everyone on board all right let's create something so um I'm creating in this TopBraid EDG user interface I am creating a small ontology and we are using the term ontology here in the sense of a data model for for some you know for classes properties and instances and there there are many ways of defining ontology some people are just using RDFS Schema others are using OWL we have moved to SHACL for that job so we have kept the term ontology for that and I'll just create a small ontology called TheOnt, just so that you have a small name as a prefix as well so and this ontology is going to build on top of SKOS, so I'm just to get started I'm including a smallest SKOS ontology which is also written in SHACL just to have something as a foundation alright so now this is the TopBriad EDG ontology editor now this is the main screen that we will be in for the next couple of minutes and consists of multiple panels here like we have the class hierarchy here we have main form view here in the center we have another view down here and if you click on a class you get to see the details of the class definition and the properties that it has defined and other stuff so this is not just a normal class in the sense of say an OWL class, it is in fact an OWL class here this is this SKOS Concept class it's also a Node Shape and this is a term from SHACL it's and this is kind of you can think of Node Shape as a type of a class it's similar to a class because it also defines a collection of properties that typically belong together to describe an object yeah and in the case of SKOS concept there are already lots of properties defined and you can see here them here like the preferred label and broader narrower and so on they are all here.

	So I can now start creating some additional classes and as I'm using the user interface I'm also going to show you the source code that is behind what		So I can now start creating some additional classes and as I'm using the user interface I'm also going to show you the source code that is behind what
	I'm doing so it's not just the graphics okay so let's create a very small ontology with just two classes to keep it simple and so that we can get along with the time that limited time that we have so let's create a class city and every dialogue here and top right has a preview button that allows you to see the triples that are being created and I must assume that you all understand turtle a little bit at least that you can read this what this means so when		I'm doing so it's not just the graphics okay so let's create a very small ontology with just two classes to keep it simple and so that we can get along with the time that limited time that we have so let's create a class city and every dialogue here and top right has a preview button that allows you to see the triples that are being created and I must assume that you all understand turtle a little bit at least that you can read this what this means so when
	you're creating a class the class will be both the class and a note shape and		you're creating a class the class will be both the class and a note shape and well in this case I've created a sub class of scores concept so let's do this
	well in this case I've created a sub class of scores concept so let's do this		now if you find a class City and let's say we want for every city we want to store say the number of inhabitants so the population so to do that well click
	now if you find a class City and let's say we want for every city we want to		here create attribute and in this dialogue then I can say well what what is my property doing so it's called population and well I could add a description not necessary I would say it's optional it doesn't have to be specified and the data type is integer okay and typically it should be a positive value at least not negative yeah so this is now a dialogue to create what's called a property shape and if you look at the preview this basically means that the node shape is going to point at a property shape so there's a property or that it's called Sh property which links the node shape that I've just created the city node shape with the property definition and the property definition then is an instance of property shape which typically or should have a name which is for display purposes and then it has a number of constraints but most importantly it must have a path and the
	store say the number of inhabitants so the population so to do that well click
	here create attribute and in this
	dialogue then I can say well what what is my property doing so it's called population and well I could add a
	description not necessary I would say it's optional it doesn't have to be specified and the data type is integer
	okay and typically it should be a positive value at least not negative
	yeah so this is now a dialogue to create what's called a property shape and if
	you look at the preview this basically means that the node shape is going to
	point at a property shape so there's a property or that it's called Sh property
	which links the node shape that I've just created the city node shape with the property definition and the property
	definition then is an instance of property shape which typically or should have a name which is
	for display purposes and then it has a number of constraints but most importantly it must have a path and the
	path is basically specifying the RDF property or SHACL 1.1 path expression		path is basically specifying the RDF property or SHACL 1.1 path expression
	as SPARQL 1.1 it was path expression too if it's more complicating for example		as SPARQL 1.1 it was path expression too if it's more complicating for example

Marco at 17:26, 14 November 2025

2025-11-14T17:26:56Z

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	Lotico Event<br>		Lotico Event<br>
	[[The Many Shapes of SHACL]]		[[The Many Shapes of SHACL]] with [[Holger Knublauch]] on June 18, 2020

	Thanks [[Marco Neumann\|Marco]] for the invite and for having the pleasure to present to you all today. When we originally set this up or talked about this we wanted to make this a rather advanced or futuristic talk about where should SHACL go. As it turned out from the first rounds of feedback there were lots of newcomers still so I'm trying to find a balance between some advanced stuff and still trying to also give an introduction to SHACL for those who have never really used it.		Thanks [[Marco Neumann\|Marco]] for the invite and for having the pleasure to present to you all today. When we originally set this up or talked about this we wanted to make this a rather advanced or futuristic talk about where should SHACL go. As it turned out from the first rounds of feedback there were lots of newcomers still so I'm trying to find a balance between some advanced stuff and still trying to also give an introduction to SHACL for those who have never really used it.

Marco at 17:26, 14 November 2025

2025-11-14T17:26:18Z

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			Lotico Event<br>
			[[The Many Shapes of SHACL]]

	Thanks [[Marco Neumann\|Marco]] for the invite and for having the pleasure to present to you all today. When we originally set this up or talked about this we wanted to make this a rather advanced or futuristic talk about where should SHACL go. As it turned out from the first rounds of feedback there were lots of newcomers still so I'm trying to find a balance between some advanced stuff and still trying to also give an introduction to SHACL for those who have never really used it.		Thanks [[Marco Neumann\|Marco]] for the invite and for having the pleasure to present to you all today. When we originally set this up or talked about this we wanted to make this a rather advanced or futuristic talk about where should SHACL go. As it turned out from the first rounds of feedback there were lots of newcomers still so I'm trying to find a balance between some advanced stuff and still trying to also give an introduction to SHACL for those who have never really used it.

Marco at 15:26, 14 November 2025

2025-11-14T15:26:36Z

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	~~Thank you~~ [[Marco Neumann\|Marco]] for the invite and for having the pleasure to present to you all today. When we originally set this up or talked about this we wanted to make this a rather advanced or futuristic talk about where SHACL ~~should~~ go. As it turned out from the first rounds of feedback there were lots of newcomers still so I'm trying to find a balance between some advanced stuff and still trying to also give an introduction to SHACL for those who have never really used it. So I have exactly three slides of PowerPoint and the first one is just the title, the second one is the overview, so what am i planning to show in this hour roughly so first I'm walking through a couple of examples of building things in SHACL and along the way try to explain some of the main ideas of SHACL then I'll show how SHACL can be used in practice for example for creating user interfaces like form editors and search and so on this will also include some part of talking about validation then I moved to inference rules which is a technique to create new facts out of existing facts then I'll show some generative features where SHACL used to drive ~~trace in~~ integration through ~~graph QL~~ and then in the end I have something new to show which will hopefully be interesting to some people ~~all right~~ so let's get started so um I was preparing for this by trying to find a list of implementations that now exist of SHACL and I found rather encouraging so because SHACL hasn't been around for that long has become a standard just three years ago and the first one and a half years or so it was a rather slow start but now we have fairly a long list of existing implementations out there and in particular basically every platform in the world is now covered so we have you know there's ~~dotnet~~ implementation there's one a couple of of Java based implementations there is one for Python, one in JavaScript at least one and so and so on and and all the the usual suspects the big triple store vendors are also on board and even the company that is not even using our RDF their main ~~draft~~ language, even ~~neo4j~~ has now started to use SHACL and support SHACL so it seems to have arrived in the market and it's hopefully not going away anytime soon. All right, so...		Thanks [[Marco Neumann\|Marco]] for the invite and for having the pleasure to present to you all today. When we originally set this up or talked about this we wanted to make this a rather advanced or futuristic talk about where should SHACL go. As it turned out from the first rounds of feedback there were lots of newcomers still so I'm trying to find a balance between some advanced stuff and still trying to also give an introduction to SHACL for those who have never really used it.

			So, I have exactly three slides of PowerPoint and the first one is just the title, the second one is the overview, so what am i planning to show in this hour roughly so first I'm walking through a couple of examples of building things in SHACL and along the way try to explain some of the main ideas of SHACL then I'll show how SHACL can be used in practice for example for creating user interfaces like form editors and search and so on this will also include some part of talking about validation, then I moved to inference rules which is a technique to create new facts out of existing facts then I'll show some generative features where SHACL used to drive JSON integration through GraphQL and then in the end I have something new to show which will hopefully be interesting to some people. Alright so let's get started so um I was preparing for this by trying to find a list of implementations that now exist of SHACL and I found rather encouraging so because SHACL hasn't been around for that long has become a standard just three years ago and the first one and a half years or so it was a rather slow start but now we have fairly a long list of existing implementations out there and in particular basically every platform in the world is now covered so we have you know there's dotNet implementation there's one a couple of of Java based implementations there is one for Python, one in JavaScript at least one and so and so on and and all the the usual suspects the big triple store vendors are also on board and even the company that is not even using our RDF their main graph language, even Neo4j has now started to use SHACL and support SHACL so it seems to have arrived in the market and it's hopefully not going away anytime soon. All right, so...

	SHACL Quick Start and Overview		SHACL Quick Start and Overview

	When I was thinking about how to introduce SHACL there are various ways in which you could do that and some people prefer to learn a new language by looking at the manuals are looking at		When I was thinking about how to introduce SHACL there are various ways in which you could do that and some people prefer to learn a new language by looking at the manuals are looking at
	the specifications even that is one approach so if you go to the official main document for SHACL which is this one yeah you can theoretically try to learn SHACL from this but I don't think that's a good idea it's formal specification it means it is written for more for computers and for implementers than for users so if you try to come this way you will be confronted with terms like well ~~focus nodes target node~~ and ~~no trades~~ and ~~shapes graph~~ and all these terms will be new and you'll be probably not really understand what they mean in the first round so what I'm trying to do in that and my preferred way of talking about SHACL is to connect it to something that people already know and already familiar with and I guess everyone at least in this audience should be familiar with concepts like classes instances and properties ~~so I'm~~ that's where I'm going to start as a way of explaining SHACL the basic ideas and then I'm moving forwards explaining well what can SHACL do what other approaches can not do as well I hope I can get across that SHACL is not rocket science, in particular if you have reasonable tools that help you with the job. Speaking about tools I'm going to show obvsiouly as a person who has been developing such tools and in the last many years I'm going to show one of those tools that we have built and that we are using using for SHACL development as well called TopBraid EDG if anyone is interested in also using this this tool can be downloaded for free basically what you need to do is you need to download top right composer which for which there is a free evaluation period of a month or so once you have downloaded this you will find a small button here called ~~top right applications~~ open TopBraid EDG and then basically this is opening this in your web browser because TopBraid EDG in principle is a web-based tool it's not a desktop tool yeah so that's how you would end up with this and which is also my starting point for what I'm trying to show so I'd like to use this now to build a small ontology in SHACL and along the way explain a few things and for those who already very familiar with SHACL apologies I know this will be recorded so many people may also come across this presentation so I'm trying to get everyone or keep everyone on board all right let's create something so um I'm creating in this TopBraid EDG user interface I am creating a small ontology and we are using the term ontology here in the sense of a data model for for some you know for classes properties and instances and there there are many ways of defining ontology some people are just using ~~rdf schema~~ others are using owl we have moved to SHACL for that job so we have kept the term ontology		the specifications even that is one approach so if you go to the official main document for SHACL which is this one yeah you can theoretically try to learn SHACL from this but I don't think that's a good idea it's formal specification it means it is written for more for computers and for implementers than for users. So if you try to come this way you will be confronted with terms like well Focus Nodes, Target Node and Node Shapes and Shapes Graph and all these terms will be new and you'll be probably not really understand what they mean in the first round so what I'm trying to do in that and my preferred way of talking about SHACL is to connect it to something that people already know and already familiar with and I guess everyone at least in this audience should be familiar with concepts like classes, instances and properties. So that's where I'm going to start as a way of explaining SHACL, the basic ideas and then I'm moving forwards explaining well what can SHACL do what other approaches can not do as well. I hope I can get across that SHACL is not rocket science, in particular if you have reasonable tools that help you with the job.
	for that and I'll just create a small ontology called ~~the aunt~~ just so that
	you have a small name as a prefix as well so and this ontology is going to		Speaking about tools I'm going to show obvsiouly as a person who has been developing such tools and in the last many years I'm going to show one of those tools that we have built and that we are using using for SHACL development as well called TopBraid EDG if anyone is interested in also using this this tool can be downloaded for free basically what you need to do is you need to download top right composer which for which there is a free evaluation period of a month or so once you have downloaded this you will find a small button here called TopBraid Applications open TopBraid EDG and then basically this is opening this in your web browser because TopBraid EDG in principle is a web-based tool it's not a desktop tool yeah so that's how you would end up with this and which is also my starting point for what I'm trying to show so I'd like to use this now to build a small ontology in SHACL and along the way explain a few things and for those who are already very familiar with SHACL apologies I know this will be recorded so many people may also come across this presentation so I'm trying to get everyone or keep everyone on board all right let's create something so um I'm creating in this TopBraid EDG user interface I am creating a small ontology and we are using the term ontology here in the sense of a data model for for some you know for classes properties and instances and there there are many ways of defining ontology some people are just using RDFS Schema others are using owl we have moved to SHACL for that job so we have kept the term ontology for that and I'll just create a small ontology called TheOnt, just so that you have a small name as a prefix as well so and this ontology is going to build on top of SKOS, so I'm just to get started I'm including a smallest SKOS ontology which is also written in SHACL just to have something as a foundation alright so now this is the ToopBriad EDG ontology editor now this is the main screen that we will be in for the next couple of minutes and consists of multiple panels here like we have the class hierarchy here we have main form view here in the center we have another view down here and if you click on a class you get to see the details of the class definition and the properties that it has defined and other stuff so this is not just a normal class in the sense of say an OWL class, it is in fact an OWL class here this is this SKOS Concept class it's also a Node Shape and this is a term from SHACL it's and this is kind of you can think of Node Shape as a type of a class it's similar to a class because it also defines a collection of properties that typically belong together to describe an object yeah and in the case of SKOS concept there are already lots of properties defined and you can see here them here like the preferred label and broader narrower and so on they are all here.
	build on top of ~~scores~~ so I'm just to get started I'm including a smallest
	~~course~~ ontology which is also written in ~~tracker~~ just to have something as a		So I can now start creating some additional classes and as I'm using the user interface I'm also going to show you the source code that is behind what
	foundation alright so now this is the ~~top right~~ EDG ontology editor now this is the main screen that we will be in for the next couple of minutes and consists of multiple panels here like we have the		I'm doing so it's not just the graphics okay so let's create a very small ontology with just two classes to keep it simple and so that we can get along with the time that limited time that we have so let's create a class city and every dialogue here and top right has a preview button that allows you to see the triples that are being created and I must assume that you all understand turtle a little bit at least that you can read this what this means so when
	class hierarchy here we have main form view here in the center we have another view down here and if you click on a class you get to see the details of the class definition and the properties that
	it has defined and other stuff so this is not just a normal class in the sense of say ~~in our~~ class it is in fact ~~in our~~ class here this is this ~~course concept~~
	class it's also a ~~node shape~~ and this is a term from ~~tracker~~ it's and this is kind of you can think of ~~note rape~~ as a type of a class it's similar to a class because it also defines a collection of
	properties that typically belong together to describe an object yeah and in the case of ~~Scots~~ concept there are
	already lots of properties defined and you can see here them here like the preferred label and broader narrower and
	so on they are all here so I can now start creating some
	additional classes and as I'm using the user interface I'm also going to show you the source code that is behind what
	I'm doing so it's not just the graphics okay so let's create a very small ontology
	with just two classes to keep it simple and so that we can get along with the time that limited time that we have so
	let's create a class city and every
	dialogue here and top right has a preview button that allows you to see the triples that are being created and I
	must assume that you all understand turtle a little bit at least that you can read this what this means so when
	you're creating a class the class will be both the class and a note shape and		you're creating a class the class will be both the class and a note shape and
	well in this case I've created a sub class of scores concept so let's do this		well in this case I've created a sub class of scores concept so let's do this