Difference between revisions of "Facet Based Resource Model"

Revision as of 15:22, 2 March 2021 (view source) Luca.frosini (Talk | contribs) (→‎Software) ← Older edit		Revision as of 15:22, 2 March 2021 (view source) Luca.frosini (Talk | contribs) (→‎Site) Newer edit →
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	| [[#Site|Site]]		| [[#Site|Site]]
	| [[#IsIdentifiedBy|IsIdentifiedBy]]		| [[#IsIdentifiedBy|IsIdentifiedBy]]
−	| align=center | 1..n	+	| align=center | 1..1
	| [[#Identifier_Facet|Identifier Facet]]		| [[#Identifier_Facet|Identifier Facet]]
	| The Site Identifier.		| The Site Identifier.

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Revision as of 15:22, 2 March 2021

Contents 1 Disclaimer 2 IS Model 2.1 Properties 2.1.1 Basic Types 2.1.2 Derived Types 2.1.3 Complex Types 2.2 Property 2.2.1 Header 2.2.2 PropagationConstraint 2.2.3 Encrypted 2.3 Entity 2.3.1 Resource 2.3.2 Facet 2.4 Relation 2.4.1 IsRelatedTo 2.4.2 ConsistsOf 2.5 Internal Entity and Relation 2.5.1 Context 2.5.2 isParentOf 2.6 Best practices and guidelines 3 gCube Model 3.1 Overview of gCube Model Resources and (isRelatedTo) Relations 3.2 gCube Model Properties 3.2.1 GCubeProperty 3.2.2 ValueSchema 3.2.3 AccessPolicy 3.3 Facets 3.3.1 Access Point Facet 3.3.2 Capability Facet 3.3.3 Contact Facet 3.3.4 Contact Reference Facet 3.3.5 Coverage Facet 3.3.6 CPU Facet 3.3.7 Descriptive Metadata Facet 3.3.8 Event Facet 3.3.9 Identifier Facet 3.3.10 License Facet 3.3.11 Location Facet 3.3.12 Memory Facet 3.3.13 Networking Facet 3.3.14 Provenance Facet 3.3.15 Schema Facet 3.3.16 Simple Facet 3.3.17 Simple Property Facet 3.3.18 Software Facet 3.3.19 State Facet 3.3.20 Subject Facet 3.4 Relations 3.4.1 isRelatedTo 3.4.1.1 Activates 3.4.1.2 BelongsTo 3.4.1.3 CallsFor 3.4.1.3.1 Discovers 3.4.1.3.2 Uses 3.4.1.4 Demands 3.4.1.5 DependsOn 3.4.1.5.1 IsPluginOf 3.4.1.6 Enables 3.4.1.7 Hosts 3.4.1.8 Involves 3.4.1.9 IsCompliantWith 3.4.1.10 IsConfiguredBy 3.4.1.11 IsCorrelatedTo 3.4.1.11.1 IsPartOf 3.4.1.12 IsCustomizedBy 3.4.1.13 IsDerivationOf 3.4.1.14 IsOwnedBy 3.4.1.15 Manages 3.4.1.16 Requires 3.4.2 ConsistsOf 3.4.2.1 IsIdentifiedBy 3.4.2.2 HasCapability 3.4.2.3 HasContact 3.4.2.3.1 HasContributor 3.4.2.3.2 HasCreator 3.4.2.3.3 HasCurator 3.4.2.3.4 HasDeveloper 3.4.2.3.5 HasMaintainer 3.4.2.3.6 HasManager 3.4.2.3.7 HasOwner 3.4.2.4 HasCoverage 3.4.2.4.1 HasSpatialCoverage 3.4.2.4.2 HasTemporalCoverage 3.4.2.5 HasMemory 3.4.2.5.1 HasPersistentMemory 3.4.2.5.2 HasVolatileMemory 3.5 Resources 3.5.1 Actor 3.5.1.1 Legal Body 3.5.1.2 Person 3.5.2 Configuration Template 3.5.2.1 Configuration 3.5.3 Dataset 3.5.3.1 Concrete Dataset 3.5.4 Schema 3.5.5 Service 3.5.5.1 EService 3.5.5.1.1 Running Plugin 3.5.5.2 Hosting Node 3.5.5.3 Virtual Machine 3.5.5.4 Virtual Service 3.5.6 Site 3.5.7 Software 3.5.7.1 Plugin 4 Extension Example 4.1 Functionality Related Facet

Disclaimer

This Model is part of research conducted in the context of a PhD. This wiki page represents just a partial view of the full rationale of the research. To have a complete overview of the rationale of the model, please refer to the PhD thesis which is publicly available at:

https://etd.adm.unipi.it/t/etd-05102019-114151/

https://openportal.isti.cnr.it/doc?id=people______::470484e51fcb9e307a418c800efc44c8

If you need to refer to such work you can cite the PhD Thesis.

BibText:

@phdthesis{frosini2019transactional,
  title={Transactional REST Information System for Federated Research Infrastructures enabling Virtual Research Environments},
  author={Frosini, Luca},
  year={2019},
  school={UNIVERSIT{\`A} DI PISA}
}

An previous paper about this work is:

BibText:

@article{frosini2018facet,
  title={A Facet-based Open and Extensible Resource Model for Research Data Infrastructures.},
  author={Frosini, Luca and Pagano, Pasquale},
  journal={Grey Journal (TGJ)},
  volume={14},
  number={2},
  year={2018}
}

IS Model

The Information System Model (henceforth IS Model) is a graph model with Entities as nodes and Relations as edges.

IS Model is used by Information System Resource Registry

• Two typologies of entities are envisaged:
  • Resources, i.e. entities representing a description of "thing" to be managed;
    • Every Resource is described by a number of Facets.
  • Facets, i.e. entities contributing to "build" a description of a Resource. Every facet, once attached to a Resource profile captures a certain aspect / characterization of the resource;
    • Every facet is characterised by a number of properties;

• Two typologies of relations are envisaged:
  • isRelatedTo, i.e. a relation linking any two Resources.
  • ConsistsOf, i.e. a relation connecting each Resource with one of the Facets characterizing it;

• Each entity and relation
  • has an header automatically generated for the sake of identification and provenance of the specific information;
  • can be specialized
    • A number of specializations are identified below. Such specializations are managed by the gCube Core services, i.e. Core services builds upon these specializations to realize its management tasks;
    • Other specializations can be defined by clients, the system make it possible to store these additional typologies of relations and facets and to discover them.
• Facet and Relation instances can have additional properties which are not defined in the schema (henceforth schema-mixed mode).
• On relations:
  • Any relation has a direction, i.e. a "source" (out bound of the relation) and a "target" (in bound of the relation). Anyway, the relation can be also navigated in the opposite direction;
  • It is not permitted to define a Relation having a Facet as "source". In other words:
    • It is not permitted to define a Relation connecting a Facet with another one;
    • It is not permitted to define a Relation connecting a Facet with a Resource (as target);
  • A Facet instance can be linked (by ConsistsOf or any specialization of it) from different Resources.

We derived the term Facet directly from the dictionary definition. Merriam Webster Dictionary defines facet as “any of the definable aspects that make up a subject (as of contemplation) or an object (as of consideration)”^[1]. The Free Dictionary defines a facet as “One of numerous aspects, as of a subject” ^[2].

Properties

Any Property defined in the schema is characterised by:

• Name : Property Name
• Type : The Type of the Property (e.g. String, Integer, ...). It can be a Basic Type or a Derived Type or a Complex Type
• Description : The description of the Property. default=null.
• Mandatory (M): Indicate if the Property is mandatory. default=false.
• ReadOnly (RO): The Property cannot change its value. default=false.
• NotNull (NN): Whether the property must assume a value diverse from 'null' or not. default=false
• Max (Max): default=null
• Min (Min): default=null
• Regex (Reg)): A Regular Expression to validate the property value, default=null. A good online tool for regex is avalable at https://regex101.com/

Basic Types

Type	Java type	Description
Boolean	java.lang.Boolean or boolean	Handles only the values True or False.
Integer	java.lang.Integer or int or java.math.BigInteger	32-bit signed Integers.
Short	java.lang.Short or short	Small 16-bit signed integers.
Long	java.lang.Long or long	Big 64-bit signed integers.
Float	java.lang.Float or float	Decimal numbers.
Double	java.lang.Double or double	Decimal numbers with high precision.
Date	java.util.Date	Any date with the precision up to milliseconds.
String	java.lang.String	Any string as alphanumeric sequence of chars.
Property	? extends org.gcube.informationsystem.model.reference.properties.Property	This is an Object contained inside the owner Entity and has no Header. It is reachable only by navigating the owner Entity.
Property list	List<? extends org.gcube.informationsystem.model.reference.properties.Property>	List of Objects contained inside the owner Entity and have no Header. They are reachable only by navigating the owner Entity.
Property set	Set<? org.gcube.informationsystem.model.reference.properties.Property>	Set (no duplicates) of Objects contained inside the owner Entity and have no Header. They are reachable only by navigating the owner Entity.
Property map	Map<String, ? extends org.gcube.informationsystem.model.reference.properties.Propertyd>	Map of Objects contained inside the owner Entity and have no Header. They are reachable only by navigating the owner Entity.
Byte	java.lang.Byte or byte	Single byte. useful to store small 8-bit signed integers.
Binary	java.lang.Byte[] or byte[]	Can contain any value as byte array.

Derived Types

The following are obtained using a String as real type and adding a validation regex.

Type	Java type	Description
Enum	java.lang.Enum or enum	by default it is represented using the String representation of the Enum. So that the primitive type used will be String. The enumeration is checked by setting Regexpr property. The Regular Expression is auto-generated and it will be something like ^(FIRST-ENUM-STRING_REPRESENTATION|SECOND-ENUM-STRING_REPRESENTATION|...|LAST_ENUM_STRING_REPRESENTATION)$. Otherwise (if indicated using an annotation), it can be represented using the Integer value of the Enum. So that the primitive type used will be Integer. The enumeration is checked using Max and Min properties.
UUID	java.util.UUID	String representation of the UUID. The check is obtained using the regular expression ^([a-fA-F0-9]{8}-[a-fA-F0-9]{4}-[a-fA-F0-9]{4}-[a-fA-F0-9]{4}-[a-fA-F0-9]{12}){1}$
URL	java.net.URL	String representation of the URL. No check actually.
URI	java.net.URI	String representation of the URI. No check actually.
TypeVersion	org.gcube.informationsystem.utils.TypeVersion	A type representing and validating a version in the following format X.X.X Major(Integer).Minor(Integer).Revision(Integer) (e.g 1.0.0, 2.3.0, 2.0.1). The check is obtained using the regular expression ^[1-9][0-9]{0,}\.(0|([1-9][0-9]{0,}))\.(0|([1-9][0-9]{0,}))$.

Complex Types

Any property defined by composing basic types derives from Property type.

Property

It does not define any field. It is just used as a base class.

The Java Interface declaration for such a type is available at:

https://code-repo.d4science.org/gCubeSystem/information-system-model/src/branch/master/src/main/java/org/gcube/informationsystem/model/reference/properties/Property.java

Header

Every Entity and Relation has an Header automatically created/updated by the System.

Header extends Property

Name	Type	Attributes	Description
uuid	UUID	Mandatory=true NotNull=true ReadOnly=true	This UUID is be used to identify the Entity or the Relation univocally.
creator	String	Mandatory=true NotNull=true ReadOnly=true	The user that created the Entity or the Relation. It is initialized at creation time.
modifiedBy	String	Mandatory=true NotNull=true	The user that made the last update to the Entity or the Relation. At creation time, it assumes the same value of creator.
creationTime	Date	Mandatory=true NotNull=true ReadOnly=true	Creation time. It represents the difference, measured in milliseconds, between the creation time and midnight, January 1, 1970, UTC.
lastUpdateTime	Date	Mandatory=true NotNull=true	Last Update time. At creation time it assumes the same value of creationTime. It represents the difference, measured in milliseconds, between the creation time and midnight, January 1, 1970, UTC.

The Java Interface declaration for such a type is available at:

https://code-repo.d4science.org/gCubeSystem/information-system-model/src/branch/master/src/main/java/org/gcube/informationsystem/model/reference/properties/Header.java

PropagationConstraint

At any time entities and relations can be added or removed to/from a context or deleted. The PropagationConstraint property contained in each relation is a predefined Property type which indicates the behaviour to be held on a target entity when an event related to a context occurs in the source resource or directly to the relation.

PropagationConstraint extends Property

Name	Type	Attributes	Description
remove	Enum	Regex=(cascadeWhenOrphan|cascade|keep)	It indicates the behaviour to implement for the target Entity when a 'remove' action is performed on the source Resource. Remove actions are: (i) the operation of removing an instance from a context; (ii) the operation of deleting an instance (it has an impact on all contexts).
add	Enum	Regex=(propagate|unpropagate)	It indicates the behaviour to implement for the target Entity when an 'add' action is performed on the source Resource. Add action is the operation of adding an instance to a context.

Remove values;

• cascadeWhenOrphan: When a remove action is performed on the source Entity of the relation, or directly on the relation, then the same remove action apart on the relation is performed to the target entity if it has no other incoming relations.
• cascade: When a remove action is performed on the source Entity of the relation, or directly on the relation, then the same remove action is performed on the relation and its target entity.
• keep: When a remove action is performed on the source Entity of the relation, or directly on the relation, then the same remove action is performed on relation but never to the target entity.

Add values;

• propagate: When an 'add' action is performed on the source Entity of the relation, or directly on the relation, then the same add action is performed on the relation and its target Entity.
• unpropagate: When an 'add' action is performed on the source Entity of the relation, is performed on source relation only. Trying to perform an 'add' action on the relation has no effects.

Any Relation contains such a property. If the values are not specified at creation time the system initialize it with the following rules:

• ConsistsOf Relation : remove=cascadeWhenOrphan, add=propagate
• IsRelatedTo Relation : remove=keep, add=unpropagate

The Java Interface declaration for such a type is available at:

https://code-repo.d4science.org/gCubeSystem/information-system-model/src/branch/master/src/main/java/org/gcube/informationsystem/model/reference/properties/PropagationConstraint.java

Encrypted

Encrypted extends Property

Name	Type	Attributes	Description
value	String		The encrypted value. The resource registry store safely the value. When received the value is decrypted using the key of current context and store the value safely. When the value is read, the resource-registry retrieve the value and encrypt it with the key of current context.

The Java Interface declaration for such a type is available at:

https://code-repo.d4science.org/gCubeSystem/information-system-model/src/branch/master/src/main/java/org/gcube/informationsystem/model/reference/properties/Encrypted.java

Entity

Abstract Entity

Goal: This is the base type for any entity.
Properties
Name	Type	Attributes	Description
header	Header	Mandatory=true NotNull=true ReadOnly=true	A distinguishing string to be used by clients to identify the access point of interest.

The Java Interface declaration for such a type is available at:

https://code-repo.d4science.org/gCubeSystem/information-system-model/src/branch/master/src/main/java/org/gcube/informationsystem/model/reference/entities/Entity.java

Resource

Abstract Resource extends Entity

Scope: This entity is conceived to describe every "main thing" to be registered and discovered by the Information System.
Source	Relation	Multiplicity	Target	Description
Facets
Resource	ConsistsOf	1..n	Facet	Any Resource consist of one or more Facets which describes the different aspects of the resource.
Relations
Resource	isRelatedTo	0..n	Resource	Any Resource can be related to any other resource.

The Java Interface declaration for such a type is available at:

https://code-repo.d4science.org/gCubeSystem/information-system-model/src/branch/master/src/main/java/org/gcube/informationsystem/model/reference/entities/Resource.java

Facet

Facets are collections of attributes conceived to capture a certain feature / aspect of the Resource they are associated with. Every facet can define zero or more properties. Besides the per-facet envisaged properties, clients can add new ones.

Abstract Facet extends Entity

Goal: This is the base type for any Facet.
Known Usage
Source	Relation	Multiplicity	Target	Description
Resource	ConsistsOf	1..n	Facet	Any Resource consist of one or more Facets which describes the different aspects of the resource.

The Java Interface declaration for such a type is available at:

https://code-repo.d4science.org/gCubeSystem/information-system-model/src/branch/master/src/main/java/org/gcube/informationsystem/model/reference/entities/Facet.java

Relation

Every relation has:

• An Header
• A PropagationConstraint
• Zero or More properties (not necessarily predefined, similarly to Facets).

The Java Interface declaration for such a type is available at:

https://code-repo.d4science.org/gCubeSystem/information-system-model/src/branch/master/src/main/java/org/gcube/informationsystem/model/reference/relations/Relation.java

IsRelatedTo

IsRelatedTo extends Relation

Source	Relation	Multiplicity	Target	Description
Resource	IsRelatedTo	0..n	Resource	A relation linking any two Resources.

The Java Interface declaration for such a type is available at:

https://code-repo.d4science.org/gCubeSystem/information-system-model/src/branch/master/src/main/java/org/gcube/informationsystem/model/reference/relations/IsRelatedTo.java

ConsistsOf

ConsistsOf extends Relation

Source	Relation	Multiplicity	Target	Description
Resource	ConsistsOf	1..n	Facet	A relation connecting each Resource with one of the Facet characterizing it.

The Java Interface declaration for such a type is available at:

https://code-repo.d4science.org/gCubeSystem/information-system-model/src/branch/master/src/main/java/org/gcube/informationsystem/model/reference/relations/ConsistsOf.java

Internal Entity and Relation

For internal use only are defined the following entity and relation:

• Context
• isParentOf

Context

Model a Context (aka scope) in the same Application Domain.

Context

Goal: Models a Context (aka scope).
Properties
Name	Type	Attributes	Description
name	String	Mandatory=true NotNull=true	The name of the context. Two Context with the same name can exist but they cannot have the same parent. In other words, a Context cannot have two children with the same name.
Known Usage
Source	Relation	Multiplicity	Target	Description
Context	isParentOf	0..n	Context	...

isParentOf

This relation has no propagation constraint.

Source	Relation	Multiplicity	Target	Description
Context	isParentOf	0..n	Context	...

Best practices and guidelines

• On Facet instances "reuse" across Resource Profiles:
  • This can be guaranteed automatically by the system, if and just in the case the system wants to avoid duplication of information. It is based on a configuration policy;
  • This MUST be done only when a change in a facet instance MUST affect a change in all Resources connected to such a Facet.

gCube Model

gCube Model is a resource model built on top of IS Model which captures the different aspects of the resources and their relations playing significant roles in a research infrastructure empowered by gCube.

Overview of gCube Model Resources and (isRelatedTo) Relations

gCube Model Properties

GCubeProperty

GCubeProperty extends Property

Goal: Marker type for any properties extended in the gCube Model.
Name	Type	Attributes	Description
This type does not define any additional attributes.

The Java Interface declaration for such a type is available at:

https://code-repo.d4science.org/gCubeSystem/gcube-model/src/branch/master/src/main/java/org/gcube/resourcemanagement/model/reference/properties/GCubeProperty.java

ValueSchema

This type aims at exposing a value which can be automatically managed by any client with no knowledge of its format.

ValueSchema extends GCubeProperty

Name	Type	Attributes	Description
value	String	Mandatory=true NotNull=true	The value which schema is available at the URI provided in the schema property
schema	URI	Mandatory=true NotNull=true	An URI containing a schema used to validate/interpret the content of the value. It is only an informative field. The validation is charge of the client.

The client can retrieve the schema at the provided URI, i.e., schema property, and use its content to understand/validate/manipulate the information contained in the value property. The client must have the capability to understand the semantics of content retrieved at the URI endpoint. Examples of application of such type are eXtensible Markup Language (XML) values which can be validated by a Document Type Definition (DTD) or XML Schema Definition (XSD).

The Java Interface declaration for such a type is available at:

https://code-repo.d4science.org/gCubeSystem/gcube-model/src/branch/master/src/main/java/org/gcube/resourcemanagement/model/reference/properties/ValueSchema.java

AccessPolicy

AccessPolicy extends Property

Name	Type	Attributes	Description
policy	Property (i.e. ValueSchema)
note	String

Facets

Early ideas and thinking on facets were documented at 2nd Generation Resource Model : Facets

Access Point Facet

Access Point Facet extends Facet

Goal: This facet captures information on an 'access point' of a resource, i.e., any web-based endpoint to programmatically interact with the resource via a known protocol. For example, it is used to define the network endpoint to contact the service. The endpoint can expose a well-known high-level protocol. For example, it is used to define the network endpoint to contact the service. The endpoint can expose a well-known high-level protocol.
Properties
Name	Type	Attributes	Description
entryName	String		A distinguishing string to be used by clients to identify the access point of interest.
endpoint	URI	Mandatory=true ReadOnly=true NotNull=true	The URI which characterises the specific endpoint instance.
protocol	String		The high-level protocol used by the access point. The String could contain the version if needed. e.g., Web Map Service (WMS) and not HyperText Transfer Protocol (HTTP) which is already contained in the URI.
description	String		A human oriented text accompanying the access point.
authorization	Property		Contains authorisation information. e.g., a token, the couple username:password, etc.
Known Usage
Source	Relation	Multiplicity	Target	Description
Dataset	ConsistsOf	0..n	Access Point Facet	Each access point captures a possible web-based method for accessing the dataset. Any embargo-related information can be captured by the access policy property of the ConsistsOf.
Concrete Dataset	ConsistsOf	1..n	Access Point Facet	Each access point captures a possible web-based method for accessing the dataset. Any embargo-related information can be captured by the access policy property of the ConsistsOf.
EService	ConsistsOf	1..n	Access Point Facet	Each access point captures a possible web-based method for accessing the service.
Software	ConsistsOf	1..n	Access Point Facet	Each access point captures a possible web-based method for accessing a software manifestation. Examples are links to maven artifact on nexus, javadoc, wiki, svn, etc.

Capability Facet

Capability Facet extends Facet

Goal: This facet captures a defined facility for performing a specified task supported by a given Service or Software;
Properties
Name	Type	Attributes	Description
name	String	Mandatory=true ReadOnly=true NotNull=true	The distinguishing name of the capability.
description	String		A human oriented description of the capability.
qualifier	String		A string used to specialize the capability.
Known Usage
Source	Relation	Multiplicity	Target	Description
Service	HasCapability	0..n	Capability Facet	To capture one of the facilities supported by the Service.
Software	HasCapability	0..n	Capability Facet	To capture one of the facilities supported by the Software.

Contact Facet

Contact Facet extends Facet

Goal: This facet captures information on a point of contact for the resource, i.e. a person or a department serving as the coordinator or focal point of information concerning the resource. As you can see in the known usages part, there are diverse points of contact that can be associated to a given resource and the role of the association is captured by using a specific relation.
Properties
Name	Type	Attributes	Description
title	String	Mandatory=false	A name describing the profession or marital status of the point of contact. E.g. Dr, Mrs, Mr.
name	String	Mandatory=true NotNull=true	First Name
middleName	String	Mandatory=false	Middle Name
surname	String	Mandatory=true NotNull=true	Surname
eMail	String	Mandatory=true NotNull=true Regex=^[a-z0-9._%+-]{1,128}@[a-z0-9.-]{1,128}	A restricted range of RFC‑822 compliant email address. Please note that just domain based email address are accepted (not IP based). Please also note that new TLD are also accepted (e.g luca@google without .com which is a valid email address). You can test here the provided regular expression with your input email address https://regex101.com/ before open a ticket.
Known Usage
Source	Relation	Multiplicity	Target	Description
Actor	IsIdentifiedBy	1..n	Contact Facet	An Actor must have at least a primary point of contact which will be used for identification purposes.
Actor	HasContact	0..n	Contact Facet	An Actor can have an arbitrary number of points of contact which provide secondary contact information.
Legal Body	IsIdentifiedBy	1..n	Contact Facet	A Legal Body must have at least a point of contact which permit to identify the Legal Body per se.
Person	IsIdentifiedBy	1..n	Contact Facet	A Person must have at least a point of contact which permit to identify the Person per se.
Dataset	HasContact	1..n	Contact Facet	A Dataset must have at least a point of contact to be used to acquire information on it.
Dataset	HasContributor	0..n	Contact Facet	One of the dataset contributors.
Dataset	HasCreator	0..n	Contact Facet	One of the dataset creators.
Dataset	HasCurator	0..n	Contact Facet	One of the dataset curators.
Dataset	HasMaintainer	0..n	Contact Facet	One of the dataset maintainers.
Dataset	HasOwner	0..n	Contact Facet	One of the dataset owners.
Concrete Dataset	HasMaintainer	1..n	Contact Facet	A Concrete Dataset must have at least a Maintainer.
Schema	HasContact	1..n	Contact Facet	A Site must have at least a point of contact to be used to acquire information on it.
Site	HasContact	1..n	Contact Facet	A Site must have at least a point of contact to be used to acquire information on it.
Site	HasMaintainer	1..n	Contact Facet	A Site must have at least a Maintainer.
Site	HasManager	1..n	Contact Facet	A Site must have at least a Manager.

Contact Reference Facet

Contact Reference Facet extends Facet

Goal: This facet captures information on the primary and authoritative contact for the resource it is associated with.
Properties
Name	Type	Attributes	Description.
website	URL		The main website.
address	String		A physical address.
phoneNumber	String		A phone number.
Known Usage
Source	Relation	Multiplicity	Target	Description
Actor	ConsistsOf	0..n	Contact Reference Facet	The primary contact information for the Actor it is attached to.
Legal Body	ConsistsOf	0..n	Contact Reference Facet	The primary contact information for the Legal Body it is attached to.
Person	ConsistsOf	0..n	Contact Reference Facet	The primary contact information for the Person it is attached to.

Coverage Facet

Coverage Facet extends Facet

Goal: This facet captures information on the extent of the Resource, i.e. any aspect aiming at capturing an indicator of the amount/area the resource covers be it a geospatial area, a temporal area, or any other "area".
Properties
Name	Type	Attributes	Description
value	String	Mandatory=true NotNull=true	The amount indicating the "area" covered by the dataset according to the reference schema.
schema	URI	Mandatory=true NotNull=true	The reference schema to be used to interpret the value.
Known Usage
Source	Relation	Multiplicity	Target	Description
Dataset	HasCoverage	1..n	Coverage Facet	...
Dataset	HasTemporalCoverage	0..n	Coverage Facet	Any temporal coverage characterising the dataset content.
Dataset	HasSpatialCoverage	0..n	Coverage Facet	Any spatial coverage characterising the dataset content.

CPU Facet

CPU Facet extends Facet

Goal: This facet captures information on the Central Processing Unit of the resource it is associated.
Properties
Name	Type	Attributes	Description
model	String	Mandatory=true NotNull=true	CPU Model.
vendor	String	Mandatory=true NotNull=true	CPU Vendor.
clockSpeed	String	Mandatory=true NotNull=true	Clock Speed with the unit.
Known Usage
Source	Relation	Multiplicity	Target	Description
Hosting Node	ConsistsOf	1..n	CPU Facet	...

Descriptive Metadata Facet

Descriptive Metadata Facet extends Facet

Goal: This facet captures information on descriptive metadata to be associated with the resource.
Properties
Name	Type	Attributes	Description
value	String	Mandatory=true NotNull=true	A metadata record representing the descriptive metadata and encoded according to the reference schema;
schema	URI	Mandatory=true NotNull=true	The reference schema to be used to interpret the value attribute;
Known Usage
Source	Relation	Multiplicity	Target	Description
Dataset	ConsistsOf	0..n	Descriptive Metadata Facet	...
Schema	ConsistsOf	0..n	Descriptive Metadata Facet	...

Event Facet

Event Facet extends Facet

Goal: This facet captures information on a certain event / happening characterising the life cycle of the resource.
Properties
Name	Type	Attributes	Description
date	Calendar	Mandatory=true NotNull=true	The time the event took place / occurred.
value	String	Mandatory=true NotNull=true	The typology of event according to the reference schema.
schema	URI		The reference schema to be used to interpret the value describing the event.
Known Usage
Source	Relation	Multiplicity	Target	Description
Dataset	ConsistsOf	0..n	Event Facet	...
EService	ConsistsOf	1..n	Event Facet	E.g. ActivationTime, DeploymentTime.
Hosting Node	ConsistsOf	1..n	Event Facet	...

Identifier Facet

Identifier Facet extends Facet

Goal: This facet captures information on Identifiers (other than the ones automatically generated by the system) that can be attached to a resource.
Properties
Name	Type	Attributes	Description
value	String	Mandatory=true NotNull=true	The identifier. E.g. http://fr.dbpedia.org/resource/Thunnus de305d54-75b4-431b-adb2-eb6b9e546014
type	Enumeration	Mandatory=true NotNull=true	The typology of identifier. I.e. URI, DOI, IRI, URL, URN, UUID.
isPersistent	boolean	Mandatory=true NotNull=true	To indicate whether the Identifier is persistent or not.
Known Usage
Source	Relation	Multiplicity	Target	Description
Configuration Template	IsIdentifiedBy	1..n	Identifier Facet	...
Configuration	IsIdentifiedBy	1..n	Identifier Facet	...
Dataset	IsIdentifiedBy	1..n	Identifier Facet	...
Concrete Dataset	IsIdentifiedBy	1..n	Identifier Facet	...
Site	IsIdentifiedBy	1..n	Identifier Facet	...

License Facet

License Facet extends Facet

Goal: This facet captures information on any license associated with the resource to capture the policies governing its exploitation and use.
Properties
Name	Type	Attributes	Description
name	String	Mandatory=true NotNull=true	The common name of the license. E.g. EUPL 1.1, GPLv2, BSD.
textURL	URL	Mandatory=true NotNull=true	The URL to the actual text of the license.
Known Usage
Source	Relation	Multiplicity	Target	Description
Dataset	ConsistsOf	0..n	License Facet	The duration of license - if any - can be captured by the expiry date defined in the ConsistsOf relation.
EService	ConsistsOf	0..n	License Facet	...
Software	ConsistsOf	1..n	License Facet	...

Location Facet

The goal of this facet is to collect information about Location

Location Facet extends Facet

Goal: This facet captures information on a physical area characterising the resource it is associated with. This should not be confused with Coverage Facet.
Properties
Name	Type	Attributes	Description
country	String		The English name of the country. See [1].
location	String		The City name.
latitude	String		Latitude.
longitude	String		Longitude.
Known Usage
Source	Relation	Multiplicity	Target	Description
Site	ConsistsOf	1..n	Location Facet	The base where the site is operated.

Memory Facet

Memory Facet extends Facet

Goal: This facet captures information on computer memory equipping the resource and its usage.
Properties
Name	Type	Attributes	Description
size	Long	Mandatory=true NotNull=true	Total amount of memory.
used	Long	Mandatory=true NotNull=true	Used amount of memory.
unit	Enum	Mandatory=true NotNull=true	The unit of measure used to report size and used attributes. Allowed values are Byte, kB (kilobyte 10^3), MB (megabyte 10^6), GB (gigabyte 10^9), TB (terabyte 10^12), PB (petabyte 10^15), EB (exabyte 10^18), ZB (zettabyte 10^21), YB (yottabyte 10^24).
Known Usage
Source	Relation	Multiplicity	Target	Description
Hosting Node	HasPersistentMemory	1..n	Memory Facet	The Disk Space allocated to the hosting node.
Hosting Node	HasVolatileMemory	1..n	Memory Facet	The RAM allocated to the hosting node.

Networking Facet

Networking Facet extends Facet

Goal: This facet captures information on any (computer) network interface/access point associated with the resource.
Properties
Name	Type	Attributes	Description
hostName	String		Host Name.
domainName	String		Domain Name.
IPAddress	String	Mandatory=true NotNull=true Regex='/^(?>(?>([a-f0-9]{1,4})(?>:(?1)){7}|(?!(?:.*[a-f0-9](?>:|$)){8,})((?1)(?>:(?1)){0,6})?::(?2)?)|(?>(?>(?1)(?>:(?1)){5}:|(?!(?:.*[a-f0-9]:){6,})(?3)?::(?>((?1)(?>:(?1)){0,4}):)?)?(25[0-5]|2[0-4][0-9]|1[0-9]{2}|[1-9]?[0-9])(?>\.(?4)){3}))$/iD'	IP Address. Validation regular expression ca be foun at http://stackoverflow.com/questions/53497/regular-expression-that-matches-valid-ipv6-addresses#answer-1934546 (Michael Rushton solution).
mask	String		Network Mask.
broadcastAddress	String		Broadcast Address.
Known Usage
Source	Relation	Multiplicity	Target	Description
Hosting Node	IsIdentifiedBy	1..n	Networking Facet	...
Site	ConsistsOf	1..n	Networking Facet	...

Provenance Facet

Provenance Facet extends Facet

Goal: This facet captures information on provenance/lineage of the entire resource.
Properties
Name	Type	Attributes	Description
relationship	Enum		I.e. wasDerivedFrom, wasGeneratedBy
reference	String		resourceID (a reference to the "originator" Resource associated to the resource the facet is attached to by the relationship)
document	String		Provenance Document E.g. the xml format
documentSchema	URI		Document Schema E.g. a reference to the format
Known Usage
Source	Relation	Multiplicity	Target	Description
Dataset	ConsistsOf	0..n	Provenance Facet

Schema Facet

Abstract Schema Facet extends Facet

Goal: This facet captures information on any schema associated with a resource.
Properties
Name	Type	Attributes	Description
name	String	Mandatory=true NotNull=true	Schema Name
description	String	Mandatory=true NotNull=true	Schema Description
schemaURL	URL		Schema definition URL (recommended)
Known Usage
Source	Relation	Multiplicity	Target	Description
Schema	IsIdentifiedBy	1..n	Schema Facet

Even is still under standardization (seems stalled) IETF is promoting a de-facto standard for JSON http://json-schema.org/. https://tools.ietf.org/html/draft-zyp-json-schema-04 https://tools.ietf.org/html/draft-fge-json-schema-validation-00 https://tools.ietf.org/html/draft-luff-json-hyper-schema-00

Simple Facet

Please do not use this Facet. Create your own type.

Simple Property Facet extends Facet

Goal: This facet is used by IS-Exporter to export old GenericResource as Configuration
Properties
No property defined
Known Usage
Source	Relation	Multiplicity	Target	Description
Configuration	ConsistsOf	1..n	Simple Facet	Used by IS-Exporter to export old GenericResource as Configuration

Simple Property Facet

Simple Property Facet extends Facet

Goal: This facet captures information on any property by a simple name-value pair.
Properties
Name	Type	Attributes	Description
name	String	Mandatory=true NotNull=true	Name
value	String	Mandatory=true NotNull=true	Value
Known Usage
Source	Relation	Multiplicity	Target	Description
Configuration Template	ConsistsOf	1..n	Simple Property Facet
Hosting Node	ConsistsOf	0..n	Simple Property Facet	E.g. to model Environment Variables

Software Facet

Software Facet extends Facet

Goal: This facet captures information on any software associated with the resource.
Properties
Name	Type	Attributes	Description
name	String	Mandatory=true NotNull=true	The name of the software artefact being described. E.g. artifactId in maven, Service Name in gCube software, the software name for retail software Microsoft Office 2013-SP2.
group	String	Mandatory=true NotNull=true	The name of "group" the software artefact belongs to. E.g. groupId in Maven, ServiceClass in gCube software, company name for retail software Microsoft Office 2013-SP2.
version	String	Mandatory=true NotNull=true	The particular release of the software artefact. E.g. maven version, Service Version in gCube software, artifactId in maven, the software version for retail software Microsoft Office 2013-SP2.
description	String		A human oriented description of the software artefact being described.
qualifier	String		E.g. packaging or scope in maven, scope level or sharable level in gCube software, target architecture for retail software x86 or amd64.
optional	Boolean		E.g. used to indicate an optional dependency both in maven as far as in gCube.
Known Usage
Source	Relation	Multiplicity	Target	Description
EService	IsIdentifiedBy	1..n	Software Facet	The software enabling the EService capabilities
EService	ConsistsOf	0..n	Software Facet	Software available in the EService environment that characterizes the specific EService instance.
Running Plugin	IsIdentifiedBy	1..1	Software Facet	The software enabling the Running Plugin.
Hosting Node	ConsistsOf	0..n	Software Facet	E.g. to report the hosted software that are not registered in the Resource Registry as Software Resource, e.g. Operating System.
Virtual Service	IsIdentifiedBy	1..n	Software Facet
Software	IsIdentifiedBy	1..n	Software Facet	Software coordinates which identify the Software per se.
Software	ConsistsOf	1..n	Software Facet	Any other software apart from the one connected with IsIdentifiedBy relation (gCube coordinates).
Plugin	IsIdentifiedBy	1..n	Software Facet	Software coordinates which identify the Plugin per se.

State Facet

The goal of this facet is to ...

Abstract State Facet extends Facet

Goal: This facet captures information on state to be associated with the resource. State is captured by any controlled vocabulary which is an integral part of the facet.
Properties
Name	Type	Attributes	Description
value	String	Mandatory=true NotNull=true	The value of the state expressed according to the schema below;
schema	URI	Mandatory=true NotNull=true	The schema that have been used to assign the state value and that must be used to properly interpret it;
Known Usage
Source	Relation	Multiplicity	Target	Description
Hosting Node	ConsistsOf	1..1	State Facet	The current state of the Hosting Node, e.g. started, ready, certified, down, failed.
EService	ConsistsOf	1..1	State Facet	The current status of the EService, e.g. started, ready, down, failed.
Software	ConsistsOf	1..n	State Facet	E.g. Deprecated, Active, Obsolete

Subject Facet

Subject Facet extends Facet

Goal: This facet captures information on subjects associated with the resource for description, classification and discovery purposes;
Properties
Name	Type	Attributes	Description
value	String	Mandatory=true NotNull=true	The value of the subject. Must be compliant with schema.
schema	URI	Mandatory=true NotNull=true	The URI of the schema subject value comes from. It is only an informative field. It is not used for validation from IS part.
Known Usage
Source	Relation	Multiplicity	Target	Description
Dataset	ConsistsOf	0..n	Subject Facet
Schema	ConsistsOf	0..n	Subject Facet

Relations

isRelatedTo

Activates

Activates extends isRelatedTo

Source	Relation	Multiplicity	Target	Description
Service	Activates	0..n	Service	...

BelongsTo

BelongsTo extends isRelatedTo

Source	Relation	Multiplicity	Target	Description
Person	BelongsTo	0..n	Legal Body	...

CallsFor

CallsFor extends isRelatedTo

Source	Relation	Multiplicity	Target	Description
Service	CallsFor	0..n	Service

Discovers

Discovers extends CallsFor

Source	Relation	Multiplicity	Target	Description
EService	Discovers	0..n	EService

Uses

Uses extends CallsFor

Source	Relation	Multiplicity	Target	Description
EService	Uses	0..n	EService

Demands

Demands extends isRelatedTo

Source	Relation	Multiplicity	Target	Description
Virtual Service	Demands	0..n	Software

DependsOn

DependsOn extends isRelatedTo

Source	Relation	Multiplicity	Target	Description
Software	DependsOn	0..n	Software

IsPluginOf

IsPluginOf extends DependsOn

Source	Relation	Multiplicity	Target	Description
Plugin	IsPluginOf	1..n	Software

Enables

Enables extends isRelatedTo

Source	Relation	Multiplicity	Target	Description
Service	Enables	0..n	Software

Hosts

Hosts extends isRelatedTo

Source	Relation	Multiplicity	Target	Description
Site	Hosts	0..n	Service

Involves

Involves extends isRelatedTo

Source	Relation	Multiplicity	Target	Description
Dataset	Involves	0..n	Actor

IsCompliantWith

IsCompliantWith extends isRelatedTo

Source	Relation	Multiplicity	Target	Description
Dataset	IsCompliantWith	0..n	Schema

IsConfiguredBy

IsConfiguredBy extends isRelatedTo

Source	Relation	Multiplicity	Target	Description
Software	IsConfiguredBy	0..n	Configuration Template

IsCorrelatedTo

IsCorrelatedTo extends isRelatedTo

Source	Relation	Multiplicity	Target	Description
Dataset	IsCorrelatedTo	0..n	Dataset

IsPartOf

IsPartOf extends IsCorrelatedTo

Source	Relation	Multiplicity	Target	Description
Concrete Dataset	IsPartOf	0..n	Dataset

IsCustomizedBy

IsCustomizedBy extends isRelatedTo

Source	Relation	Multiplicity	Target	Description
Service	IsCustomizedBy	0..n	Configuration Template

IsDerivationOf

IsDerivationOf extends isRelatedTo

Source	Relation	Multiplicity	Target	Description
Configuration	IsDerivationOf	1..1	Configuration Template

IsOwnedBy

IsOwnedBy extends isRelatedTo

Source	Relation	Multiplicity	Target	Description
Site	IsOwnedBy	0..n	Actor

Manages

Manages extends isRelatedTo

Source	Relation	Multiplicity	Target	Description
Service	Manages	0..n	Dataset

Requires

Requires extends isRelatedTo

Source	Relation	Multiplicity	Target	Description
Software	Requires	0..n	Service

ConsistsOf

IsIdentifiedBy

IsIdentifiedBy extends ConsistsOf

Source	Relation	Multiplicity	Target	Description
Definition
Resource	IsIdentifiedBy	1..n	Facet	A relation connecting each Resource with one of the Facet which can be used to identify the Resource.
Source	Relation	Multiplicity	Target	Description
Definition
Resource	IsIdentifiedBy	1..n	Facet
Known Usage
Actor	IsIdentifiedBy	1..n	Contact Facet
Legal Body	IsIdentifiedBy	1..n	Contact Facet
Person	IsIdentifiedBy	1..n	Contact Facet
Configuration Template	IsIdentifiedBy	1..n	Identifier Facet
Configuration	IsIdentifiedBy	1..n	Identifier Facet
Dataset	IsIdentifiedBy	1..n	Identifier Facet
Concrete Dataset	IsIdentifiedBy	1..n	Identifier Facet
Service	IsIdentifiedBy	1..n	Facet
EService	IsIdentifiedBy	1..1	Software Facet	...
Virtual Service	IsIdentifiedBy	1..n	Software Facet	...
Virtual Machine	IsIdentifiedBy	1..n	Software Facet	...
Schema	IsIdentifiedBy	1..n	Identifier Facet	...
Site	IsIdentifiedBy	1..n	Identifier Facet	...
Software	IsIdentifiedBy	1..n	Software Facet	Software coordinates which identify the Software per se.
Plugin	IsIdentifiedBy	1..n	Software Facet	Software coordinates which identify the Plugin per se.

HasCapability

Abstract HasCapability extends ConsistsOf

Source	Relation	Multiplicity	Target	Description
Definition
Resource	HasCapability	0..n	Capability Facet
Known Usage
Service	HasCapability	0..n	Capability Facet
Software	HasCapability	0..n	Capability Facet

HasContact

Abstract HasContact extends ConsistsOf

Source	Relation	Multiplicity	Target	Description
Definition
Resource	HasContact	0..n	Contact Facet
Known Usage
Dataset	HasContact	1..n	Contact Facet	...

HasContributor

HasContributor extends HasContact

Source	Relation	Multiplicity	Target	Description
Definition
Resource	HasContributor	0..n	Contact Facet
Known Usage
Dataset	HasContributor	0..n	Contact Facet	Is he the contributor

HasCreator

HasCreator extends HasContact

Source	Relation	Multiplicity	Target	Description
Definition
Resource	HasCreator	0..n	Contact Facet
Known Usage
Dataset	HasCreator	0..n	Contact Facet	Is he the creator

HasCurator

HasCurator extends HasContact

Source	Relation	Multiplicity	Target	Description
Definition
Resource	HasCurator	0..n	Contact Facet
Known Usage
Dataset	HasCurator	0..n	Contact Facet	Is he the curator

HasDeveloper

HasDeveloper extends HasContact

Source	Relation	Multiplicity	Target	Description
Definition
Resource	HasDeveloper	0..n	Contact Facet
Known Usage

HasMaintainer

HasMaintainer extends HasContact

Source	Relation	Multiplicity	Target	Description
Definition
Resource	HasMaintainer	0..n	Contact Facet
Known Usage
Dataset	HasMaintainer	0..n	Contact Facet	Is he the maintainer

HasManager

HasManager extends HasContact

Source	Relation	Multiplicity	Target	Description
Definition
Resource	HasManager	0..n	Contact Facet
Known Usage

HasOwner

HasOwner extends HasContact

Source	Relation	Multiplicity	Target	Description
Definition
Resource	HasOwner	0..n	Contact Facet
Known Usage
Dataset	HasOwner	0..n	Contact Facet	Is he the owner

HasCoverage

Abstract HasCoverage extends ConsistsOf

Source	Relation	Multiplicity	Target	Description
Definition
Resources	HasCoverage	0..n	Coverage Facet	...
Known Usage
Dataset	HasCoverage	1..n	Coverage Facet	...

HasSpatialCoverage

HasSpatialCoverage extends HasCoverage

Source	Relation	Multiplicity	Target	Description
Definition
Resources	HasSpatialCoverage	0..n	Coverage Facet	...
Known Usage
Dataset	HasSpatialCoverage	0..n	Coverage Facet	...

HasTemporalCoverage

HasTemporalCoverage extends HasCoverage

Source	Relation	Multiplicity	Target	Description
Definition
Resources	HasTemporalCoverage	0..n	Coverage Facet	...
Known Usage
Dataset	HasTemporalCoverage	0..n	Coverage Facet	...

HasMemory

Abstract HasMemory extends ConsistsOf

Source	Relation	Multiplicity	Target	Description
Definition
Resources	HasMemory	0..n	Memory Facet	...

HasPersistentMemory

HasPersistentMemory extends HasMemory

Source	Relation	Multiplicity	Target	Description
Definition
Resources	HasPersistentMemory	0..n	Memory Facet	...
Known Usage
Hosting Node	HasPersistentMemory	1..n	Memory Facet	Disk Space

HasVolatileMemory

HasVolatileMemory extends HasMemory

Source	Relation	Multiplicity	Target	Description
Definition
Resources	HasVolatileMemory	0..n	Memory Facet	...
Known Usage
Hosting Node	HasVolatileMemory	1..n	Memory Facet	RAM

Resources

Every Resource has:

• An Header
• One or more Facets characterizing it;
• Zero or More relation with other Resources

A class can be identified as Abstract. This means that cannot be instantiated. It is expected that one of its specializations are instantiated. It is not required that an Abstract class establishes an IsIdentifiedBy relation with a Facet.

Actor

Abstract Actor extends Resource

Scope: Any entity (human or machine) playing an active role.
Source	Relation	Multiplicity	Target	Description
Facets
Actor	IsIdentifiedBy	1..n	Contact Facet	An Actor has at least a Contact Facet which permit to identify the Actor per se.
Actor	HasContact	0..n	Contact Facet	An Actor can have other Contact Facets which provide secondary contact information.
Actor	ConsistsOf	0..n	Contact Reference Facet	...
Relations
Dataset	Involves	0..n	Actor	...
Site	IsOwnedBy	0..n	Actor	...

Legal Body

Legal Body extends Actor

Scope: A legal entity playing the role of an Actor.
Source	Relation	Multiplicity	Target	Description
Facets
Legal Body	IsIdentifiedBy	1..n	Contact Facet	A Legal Body has at least a Contact Facet which permit to identify the Legal Body per se.
Legal Body	ConsistsOf	0..n	Contact Reference Facet	...
Relations
Person	BelongsTo	0..n	Legal Body	...

Person

Person extends Actor

Scope: Any human playing the role of Actor.
Source	Relation	Multiplicity	Target	Description
Facets
Person	IsIdentifiedBy	1..n	Contact Facet	A Person has at least a Contact Facet which permit to identify the Person per se.
Person	ConsistsOf	0..n	Contact Reference Facet	...
Relations
Person	BelongsTo	0..n	Legal Body	...

Configuration Template

Configuration Template extends Resource

Scope: It represents a template for a configuration. It describe how a configuration has to be realized. E.g. Used to define the accounting configuration parameters template.
Source	Relation	Multiplicity	Target	Description
Facets
Configuration Template	IsIdentifiedBy	1..n	Identifier Facet	...
Configuration Template	ConsistsOf	1..n	Simple Property Facet	...
Relations
Configuration	IsDerivationOf	1..1	Configuration Template	...
Service	IsCustomizedBy	0..n	Configuration Template	...
Software	IsConfiguredBy	0..n	Configuration Template	...

Configuration

Configuration Profile extends Configuration Template

Scope: An instance of a configuration template characterising the behaviour and shape of the resource it is attached to.
Source	Relation	Multiplicity	Target	Description
Facets
Configuration	IsIdentifiedBy	1..n	Identifier Facet	...
Configuration	ConsistsOf	1..n	Simple Facet	Used by IS-Exporter to export old GenericResource as Configuration
Relations
Configuration	IsDerivationOf	1..1	Configuration Template	...

Dataset

Dataset extends Resource

Scope: Any set of digital objects representing data and treated collectively as a unit.
Source	Relation	Multiplicity	Target	Description
Facets
Dataset	IsIdentifiedBy	1..n	Identifier Facet	The set of Identifiers associated with the Dataset instance.
Dataset	HasContact	1..n	Contact Facet	The contact information of the entity responsible for the dataset.
Dataset	HasContributor	0..n	Contact Facet	The contact information on contributors supporting the creation and development of the Dataset.
Dataset	HasCreator	0..n	Contact Facet	The contact information of the creator of the Dataset.
Dataset	HasCurator	0..n	Contact Facet	The contact information of the entity responsible for the curation of the dataset.
Dataset	HasMaintainer	0..n	Contact Facet	The contact information of the entity responsible for the maintenance of the dataset.
Dataset	HasOwner	0..n	Contact Facet	The contact information of the entity having the ownership of the dataset.
Dataset	ConsistsOf	0..n	Access Point Facet	The access point to use for having access to the dataset. The embargoState can be modeled through the access policy defined in the ConsistsOf relation.
Dataset	ConsistsOf	0..n	License Facet	The licence governing dataset exploitation. The duration of license (if any) is captured by the expiry date defined in the ConsistsOf relation.
Dataset	ConsistsOf	0..n	Event Facet	Any "event" characterising the lifecycle of the dataset, e.g. collection date, last collection date.
Dataset	ConsistsOf	0..n	Provenance Facet	Any provenance record associated with the dataset.
Dataset	HasCoverage	1..n	Coverage Facet	Any coverage related information (e.g. topic, species) characterising the content of the dataset.
Dataset	HasTemporalCoverage	0..n	Coverage Facet	Any temporal coverage information characterising the content of the dataset, e.g. the time-span covered by the dataset.
Dataset	HasSpatialCoverage	0..n	Coverage Facet	Any geo-spatial coverage information characterising the content of the dataset, e.g. the area covered by the dataset.
Dataset	ConsistsOf	0..n	Descriptive Metadata Facet	Any descriptive information associated with the dataset, e.g. for discovery purposes.
Dataset	ConsistsOf	0..n	Subject Facet	Any subject / tag associated with the dataset for descriptive and discovery purposes.
Relations
Dataset	Involves	0..n	Actor	...
Dataset	IsCorrelatedTo	0..n	Dataset	...
Dataset	IsCompliantWith	0..n	Schema	Any schema characterising the content of the dataset, e.g. the schema describing the 'columns' of a CSV-based dataset.
Concrete Dataset	IsPartOf	0..n	Dataset	The reference to the 'incarnations' / 'manifestations' contributing to a dataset.
Service	Manages	0..n	Dataset	The link between the service that 'Manages' the dataset and the dataset, e.g. the service that Hosts the dataset and give access to it.

Concrete Dataset

Concrete Dataset extends Dataset

Scope: Any incarnation / manifestation of a dataset or part of it.
Source	Relation	Multiplicity	Target	Description
Facets
Concrete Dataset	IsIdentifiedBy	1..n	Identifier Facet	The set of Identifiers associated with the Concrete Dataset instance.
Concrete Dataset	HasMaintainer	1..n	Contact Facet	The contact information of the entity responsible for the maintenance of the concrete dataset.
Concrete Dataset	ConsistsOf	1..n	Access Point Facet	The access point to use for having access to the concrete dataset. The embargoState can be modeled through the access policy defined in the ConsistsOf relation.
Relations
Concrete Dataset	IsPartOf	0..n	Dataset	The reference to the Dataset the instance manifests / contribute to manifest.

Schema

Schema extends Resource

Scope: Any reference schema to be used to specify values compliant with it. Examples include controlled vocabularies, ontologies, etc.
Source	Relation	Multiplicity	Target	Description
Facets
Schema	IsIdentifiedBy	1..n	Schema Facet	...
Schema	HasContact	1..n	Contact Facet	...
Schema	ConsistsOf	0..n	Descriptive Metadata Facet	...
Schema	ConsistsOf	0..n	Subject Facet	...
Relations
Dataset	IsCompliantWith	0..n	Schema	...

Service

Abstract Service Profile

Scope: An abstract entity to represent any typology of Service worth registering in the infrastructure.
Source	Relation	Multiplicity	Target	Description
Facets
Service	IsIdentifiedBy	1..n	Facet	Any facet instance useful for identification purposes.
Service	ConsistsOf	0..n	Descriptive Metadata Facet	Any descriptive information associated with the service, e.g. for discovery purposes.
Service	ConsistsOf	0..n	Subject Facet	Any subject / tag associated with the service for descriptive, cataloguing and discovery purposes.
Service	HasCapability	0..n	Capability Facet	Any facility supported/offered by the Service.
Relations
Service	CallsFor	0..n	Service	A reference to the Services needed by the target instance to work.
Service	Activates	0..n	Service	The source Service Enables the target Service to be running. Examples are an Hosting Node which Enables an EService; A Virtual Machine enabling an EService or an Hosting Node; An EService enabling a Running Plugin etc.
Service	IsCustomizedBy	0..n	Configuration Template	A reference to any configuration characterising the Service behaviour.
Service	Manages	0..n	Dataset	A reference to any Dataset resource managed by the Service instance.
Service	Enables	0..n	Software	A reference to any Software the Service is enabling (i.e. the Software is running throught the EService)
Software	Requires	0..n	Service	A reference to any Service needed by a Software to properly operate, e.g. this can be used to capture a sort of run-time requirements between a software component and the Service it needs.

EService

EService extends Service

Scope: Any Electronic Service (aka Running Service) that is registered in the infrastructure and made available by an Access Point.
Source	Relation	Multiplicity	Target	Description
Facets
EService	IsIdentifiedBy	1..n	Software Facet	The main software enabling the EService capabilities.
EService	ConsistsOf	0..n	Software Facet	Software available in the EService environment that characterizes the specific EService instance.
EService	ConsistsOf	1..n	Access Point Facet	Identify the endpoints of the EService.
EService	ConsistsOf	1..n	Event Facet	Events characterising the current status and lifecycle of the service, e.g. ActivationTime, DeploymentTime.
EService	ConsistsOf	1..1	State Facet	The current status of the EService, e.g. started, ready, down, failed.
EService	ConsistsOf	0..n	License Facet	The specific terms of use governing the exploitation of the EService.
Relations
EService	Discovers	0..n	EService	A reference to any other EService, the EService instance is discovering through query on IS.
EService	Uses	0..n	EService	A reference to any other EService, the EService instance is invoking.

Running Plugin

Running Plugin extends EService

Scope: Any instance of a Plugin deployed and running by an EService.
Source	Relation	Multiplicity	Target	Description
Facets
Running Plugin	IsIdentifiedBy	1..1	Software Facet	The software enabling the Running Plugin.
Relations

Hosting Node

Hosting Node extends Service

Scope: The HostingNode represent a container capable of managing the lifecycle of an electronic service, i.e., being capable to host and operate an EService.
Source	Relation	Multiplicity	Target	Description
Facets
Hosting Node	IsIdentifiedBy	1..n	Networking Facet	The Network ID characterising the Hosting Node.
Hosting Node	ConsistsOf	1..n	CPU Facet	The CPU equipping the Hosting Node.
Hosting Node	HasPersistentMemory	1..n	Memory Facet	The Disk Space Capacity of the Hosting Node.
Hosting Node	HasVolatileMemory	1..n	Memory Facet	The RAM Capacity of the Hosting Node.
Hosting Node	ConsistsOf	1..n	Event Facet	Every event characterizing the life cycle of the Hosting Node, e.g. the activation time.
Hosting Node	ConsistsOf	1..1	State Facet	The current state of the Hosting Node, e.g. started, ready, certified, down, failed.
Hosting Node	ConsistsOf	0..n	Simple Property Facet	Any <key, value> pair property worth associating with the Hosting Node, e.g. Environment Variables.
Hosting Node	ConsistsOf	0..n	Software Facet	Any Software characterising the Hosting Node. Useful to report the hosted software that are not registered in the Resource Registry as Software Resource, e.g. Operating System.
Relations

Virtual Machine

Virtual Machine Profile extends Service Profile

Scope: A Virtual Machine is an emulation of a physical computer which appears to the running operative system as real hardware.
Source	Relation	Multiplicity	Target	Description
Facets
Virtual Machine	IsIdentifiedBy	1..n	Networking Facet	The Network ID characterising the Virtual Machine.
Relations

Virtual Service

Virtual Service Profile extends Service Profile

Scope: An abstract service (non physically existing service) worth being represented as an existing Service for management purposes. Examples of usage include cases where classes or set of services are to be managed like an existing unit.
Source	Relation	Multiplicity	Target	Description
Facets
Virtual Service	IsIdentifiedBy	1..n	Software Facet	???
Relations
Virtual Service	Demands	0..n	Software	...

Site

Site Profile extends Resource

Scope: An entity representing the location (physical or virtual) hosting and providing the resources associated with it.
Source	Relation	Multiplicity	Target	Description
Facets
Site	IsIdentifiedBy	1..1	Identifier Facet	The Site Identifier.
Site	HasContact	1..n	Contact Facet	The main contact for the Site.
Site	HasMaintainer	1..n	Contact Facet	Contact information of the maintainer of the Site.
Site	HasManager	1..n	Contact Facet	Contact information of the Site Manager.
Site	ConsistsOf	1..n	Location Facet	...
Site	ConsistsOf	1..n	Networking Facet	...
Relations
Site	IsOwnedBy	0..n	Actor	...
Site	Hosts	0..n	Service	...

Software

Software extends Resource

Scope: Any Software entity worth being represented for management purposes.
Source	Relation	Multiplicity	Target	Description
Facets
Software	IsIdentifiedBy	1..1	Software Facet	Software coordinates which identify the Software per se.
Software	ConsistsOf	1..n	Software Facet	Apart the one connected by the IsIdentifiedBy relation (gCube coordinates) the others identify the sw in other way e.g. (Maven coordinates).
Software	ConsistsOf	1..n	Access Point Facet	Links to maven artifact on nexus, javadoc, wiki, svn ...
Software	ConsistsOf	1..n	License Facet	The Software License characterizing its possible exploitation and use.
Software	ConsistsOf	1..n	State Facet	The state characterising the software, e.g. Deprecated, Active, Obsolete.
Software	HasCapability	0..n	Capability Facet	...
Relations
Software	DependsOn	0..n	Software	To capture any dependency between two software artifacts.
Software	IsConfiguredBy	0..n	Configuration Template	E.g. Accounting Sw uses it to discover the configuration.
Software	Requires	0..n	Service	to capture any dependency between a software artifact and a Service, e.g. A software requiring a specific database.
Virtual Service	Demands	0..n	Software	...
Plugin	IsPluginOf	0..n	Software	To capture the relation between a Software and its Plugins.

Plugin

Plugin extends Software

Scope: A piece of Software extending the capabilities of another Software (main) and requiring the main Software to be executed;
Source	Relation	Multiplicity	Target	Description
Facets
Plugin	IsIdentifiedBy	1..n	Software Facet	Software coordinates which identify the Plugin per se.
Relations
Plugin	IsPluginOf	1..n	Software	A reference to the Software this Plugin is conceived to extend the capabilities.

Extension Example

The gCube Resource Model supports extensions at runtime meaning that new facets, relations, and resources can be defined and registered at any time by authorized clients. Those extensions must necessarily specialize an existing gCube Entity. An example of those specializations is the following:

Functionality Related Facet

The goal of this facet is to capture what are the facilities supported by the Service Entity and it aims to model the service interface.

Functionality Related Facet extends Facet

Name	Type	Attributes	Description
name	String		...
description	String		...
input	String		...
output	String		...
Known Usage
Source	Relation	Multiplicity	Target	Description
Service	ConsistsOf	0..n	Functionality Related Facet	...

1. ↑ https://www.merriam-webster.com/dictionary/facet
2. ↑ https://www.thefreedictionary.com/facet