gem-graph-server/debian/var/models/example.xmls

<?xml version="1.0"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">

<!-- https://www.freeformatter.com/xml-validator-xsd.html -->
<!-- https://www.w3schools.com/xml/el_attribute.asp  -->
<!-- use="required" is NOT allowed in attributes declarations-->
<!-- To know : Attribute 'name' Cannot Appear In Element 'element'.-->

<!-- xs:element name="name" type="xs:string"/ -->
<!-- Cos-element-consistent: Error For Type '#AnonType_identitygem-graph-model'.
     Multiple Elements With Name 'name', With Different Types, Appear In The Model Group. -->

<xs:attribute name="id" type="xs:string"/>
<xs:attribute name="date" type="xs:integer"/>  <!--TODO  type ? -->
<xs:attribute name="name" type="xs:string"/>
<xs:attribute name="lang" type="xs:string"/>
<xs:attribute name="value" type="xs:integer"/> <!--TODO  WARNING: It's an integer !-->
<xs:attribute name="owner" type="xs:integer"/>
<xs:attribute name="author" type="xs:string"/>
<xs:attribute name="version" type="xs:float"/>
<xs:attribute name="probability" type="xs:integer"/>

<!-- TO EVALUATE   Consider using 'group' (?) or NOT -->
<!-- https://www.w3schools.com/xml/schema_complex_indicators.asp -->
<!-- TO EVALUATE   Other definitions of an arrow (coord origin + dest,...) -->
<!-- TO EVALUATE   Hypercubes pave the space => add a potential dimension 'w':
     <xs:attribute name="w" type="xs:integer" default="0"/>-->

<xs:element name="arrow">  <!-- TODO   Consider using 'group' : -->
<!-- https://www.w3schools.com/xml/schema_complex_indicators.asp -->
    <xs:complexType>
        <xs:attribute name="x" type="xs:integer" default="1"/>
        <xs:attribute name="y" type="xs:integer" default="0"/>
        <xs:attribute name="z" type="xs:integer" default="0"/>
        <xs:attribute name="site" type="xs:integer" default="1"/>
        <xs:attribute name="weight" type="xs:integer" default="0"/>
    </xs:complexType>
</xs:element>

<!-- A state can be connex or not.   A connex state is an object.
     A transition goes from an origin (state) to a target.

    Therefore, element 'State' is used in
     - objects definitions,
     - initial and produced/computed states declarations,
     - origin and target declarations of a transition.

     What attributes should always be associated to a state ? -->

<xs:element name="state">
    <xs:complexType>
    <xs:sequence minOccurs="1" maxOccurs="unbounded">
        <xs:element ref="arrow"/>
    </xs:sequence>
    <xs:attribute ref="id" use="required"/>
    <xs:attribute ref="date" use="required"/>
    <xs:attribute ref="author" use="required"/>
    </xs:complexType>
</xs:element>

<xs:element name="transition">
    <xs:complexType>
    <xs:sequence minOccurs="2" maxOccurs="2"> <!-- TODO ... Cannot use 'length' -->
        <xs:element ref="state"/>
    </xs:sequence>
    <xs:attribute ref="id" use="required"/>
    <xs:attribute ref="date" use="required"/>
    <xs:attribute ref="author" use="required"/>
    <xs:attribute ref="probability" use="required"/>
    </xs:complexType>
</xs:element>

<xs:element name="gem-graph-model">
<xs:complexType>
<xs:sequence>

    <xs:element name="identity">
        <xs:complexType>
        <xs:sequence>

            <xs:element name="name" type="xs:string"/>
            <xs:element name="owner" type="xs:integer"/>
            <xs:element name="date" type="xs:integer"/>
            <xs:element name="version" type="xs:float"/>

        </xs:sequence>
        </xs:complexType>
    </xs:element>

    <xs:element name="parameters">
        <xs:complexType>
        <xs:sequence>

            <xs:element name="modelization">
                <xs:complexType>
                <xs:sequence>

                    <xs:element name="max_thread">
                        <xs:complexType>
                            <xs:attribute ref="value" use="required"/>
                        </xs:complexType>
                    </xs:element>

                    <xs:element name="max_cycles">
                        <xs:complexType>
                            <xs:attribute ref="value" use="required"/>
                        </xs:complexType>
                    </xs:element>

                </xs:sequence>
                </xs:complexType>
            </xs:element>

            <xs:element name="space">
                <xs:complexType>
                <xs:sequence>

                    <xs:element name="dimension">
                        <xs:complexType>
                            <xs:attribute ref="value" use="required"/>
                        </xs:complexType>
                    </xs:element>

                    <xs:element name="size">
                        <xs:complexType>
                            <xs:attribute ref="value" use="required"/>
                        </xs:complexType>
                    </xs:element>

                    <xs:element name="site_multiplicity">
                        <xs:complexType>
                            <xs:attribute ref="value" use="required"/>
                        </xs:complexType>
                    </xs:element>

                    <xs:element name="boundaries">
                        <xs:complexType>
                        </xs:complexType>
                    </xs:element>

              </xs:sequence>
              </xs:complexType>
          </xs:element>

          </xs:sequence>
          <xs:attribute ref="id" use="required"/>
          <xs:attribute ref="date" use="required"/>
          <xs:attribute ref="author" use="required"/>
          </xs:complexType>
      </xs:element>

      <xs:element name="objects">
          <xs:complexType>
          <xs:sequence minOccurs="1" maxOccurs="unbounded">
              <xs:element ref="state"/>  <!--An object is a connex state -->
          </xs:sequence>
          <xs:attribute ref="id" use="required"/>
          <xs:attribute ref="date" use="required"/>
          <xs:attribute ref="author" use="required"/>
          </xs:complexType>
      </xs:element>

      <!--An initial state is made of at least one object -->
      <xs:element ref="state"/>

      <!--An produced state is made of at least one object -->
      <xs:element name="produced_states">
          <xs:complexType>
          <xs:sequence minOccurs="0" maxOccurs="unbounded">
              <xs:element ref="state"/>
          </xs:sequence>
          <xs:attribute ref="id" use="required"/>
          <xs:attribute ref="date" use="required"/>
          <xs:attribute ref="author" use="required"/>
          </xs:complexType>
      </xs:element>

      <xs:element name="transitions">
          <xs:complexType>
          <xs:sequence minOccurs="0" maxOccurs="unbounded">
              <xs:element ref="transition"/>
          </xs:sequence>
          <xs:attribute ref="id" use="required"/>
          <xs:attribute ref="date" use="required"/>
          <xs:attribute ref="author" use="required"/>
          </xs:complexType>
      </xs:element>


      <xs:element name="ref" type="xs:string"/>

      <xs:element name="quote" type="xs:string"/>

</xs:sequence>
</xs:complexType>
</xs:element>
</xs:schema>