<?xml version="1.0" encoding="UTF-8"?>
<!--

    Copyright (C) 2000 - 2024 Silverpeas

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License as
    published by the Free Software Foundation, either version 3 of the
    License, or (at your option) any later version.

    As a special exception to the terms and conditions of version 3.0 of
    the GPL, you may redistribute this Program in connection with Free/Libre
    Open Source Software ("FLOSS") applications as described in Silverpeas's
    FLOSS exception.  You should have received a copy of the text describing
    the FLOSS exception, and it is also available here:
    "https://www.silverpeas.org/legal/floss_exception.html"

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Affero General Public License for more details.

    You should have received a copy of the GNU Affero General Public License
    along with this program.  If not, see <https://www.gnu.org/licenses/>.

-->
<xs:schema xmlns="http://silverpeas.org/xml/ns/migration"
           elementFormDefault="qualified" xmlns:xs="http://www.w3.org/2001/XMLSchema"
           targetNamespace="http://silverpeas.org/xml/ns/migration"
           version="1.0">

  <xs:annotation>
    <xs:documentation>
      Copyright (C) 2000 - 2024 Silverpeas

      This program is free software: you can redistribute it and/or modify
      it under the terms of the GNU Affero General Public License as
      published by the Free Software Foundation, either version 3 of the
      License, or (at your option) any later version.

      As a special exception to the terms and conditions of version 3.0 of
      the GPL, you may redistribute this Program in connection with Free/Libre
      Open Source Software ("FLOSS") applications as described in Silverpeas's
      FLOSS exception. You should have received a copy of the text describing
      the FLOSS exception, and it is also available here:
      "https://www.silverpeas.org/legal/floss_exception.html"

      This program is distributed in the hope that it will be useful,
      but WITHOUT ANY WARRANTY; without even the implied warranty of
      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
      GNU Affero General Public License for more details.

      You should have received a copy of the GNU Affero General Public License
      along with this program. If not, see &lt;https://www.gnu.org/licenses/>.
    </xs:documentation>
  </xs:annotation>

  <xs:annotation>
    <xs:documentation xml:lang="en">
      <![CDATA[
      This schema defines the grammar of a data source migration descriptor. Each descriptor
      defines for a given Silverpeas module a set of rules to migrate the data source schema to a
      newer state (newer version).
      A Silverpeas module can be either a Silverpeas Core Engine (or API) or a Silverpeas
      component.
      The descriptor is made up of two main elements:
        - current to specify the current version of the data source schema for the Silverpeas module,
        - upgrade to specify the version from which the rules have to be applied in order to pass to
        the next version.
      Each of these elements defines a list of scripts to run in order to migrate the data source
      schema from its current version up to the latest one. A migration can be then either a fresh
      installation of the schema or an upgrade of the existing one.
      ]]>
    </xs:documentation>
  </xs:annotation>

  <xs:element name="migration">
    <xs:annotation>
      <xs:documentation xml:lang="en">
     <![CDATA[
     The migration element is the root of the migration descriptor. It is defined for a given
     Silverpeas module, and it declares the different migration rules to apply to either spawn
     the data source schema or to upgrade from all the previous versions of this schema.
     The name of the Silverpeas module is indicated by the attribute module.
      ]]>
      </xs:documentation>
    </xs:annotation>
    <xs:complexType>
      <xs:sequence>
        <xs:annotation>
          <xs:documentation>
      <![CDATA[
      The migration root element is made up of the child elements below as ordered as
      following:
        - current to specify the current version of the data source schema for the Silverpeas module,
        - upgrade to specify the version from which the rules have to be applied in order to pass to
        the next version.
      The current sub-element is mandatory whereas the upgrade sub-element can be specified one or
      several times, each of them indicating an upgrade from a given data source schema version.
      The current element accepts as attribute the current version of the data source schema
      required by the Silverpeas module. The current element defines the rules set to apply for
      a fresh installation of the Silverpeas module. The upgrade element accepts as attribute the
      actual version of the data source schema for which it has to be taken into account in order
      to upgrade the schema to the next version. Each upgrade element defines a rules set to apply
      for upgrading the data source schema from the actual version to the next one. One or more
      upgrade can be performed sequentially according to the actual version of the schema and
      the current version expected by the module.
      ]]>
          </xs:documentation>
        </xs:annotation>
        <xs:element name="current" type="CreationRule">
          <xs:annotation>
            <xs:documentation>
              <![CDATA[
              The current migration rule dedicated to the creation of the datasource for the
              underlying Silverpeas module.
              ]]>
            </xs:documentation>
          </xs:annotation>
        </xs:element>
        <xs:element name="upgrade" type="UpgradeRule" minOccurs="0" maxOccurs="unbounded">
          <xs:annotation>
            <xs:documentation>
              <![CDATA[
              Upgrade rules to upgrade the state of the data source from a given version to the
              next version. Each upgrade rules are applied from the actual state of the data source
              up to the expected state of the data source.
              ]]>
            </xs:documentation>
          </xs:annotation>
        </xs:element>
      </xs:sequence>
      <xs:attribute name="module" type="xs:normalizedString" use="required"/>
      <xs:attribute name="order" type="xs:integer"/>
    </xs:complexType>
  </xs:element>

  <xs:simpleType name="VersionID">
    <xs:annotation>
      <xs:documentation>
        <![CDATA[
        The format of a version of a data source, that is the version of its state.
        ]]>
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base="xs:integer">
      <xs:pattern value="[0-9][0-9][0-9]"/>
    </xs:restriction>
  </xs:simpleType>

  <xs:simpleType name="ScriptType">
    <xs:annotation>
      <xs:documentation>
        <![CDATA[
        A script is a file containing the statements that perform a change (or a creation) of the
        data source state.
        ]]>
      </xs:documentation>
    </xs:annotation>
    <xs:restriction base="xs:token">
      <xs:enumeration value="sql"/>
      <xs:enumeration value="groovy"/>
    </xs:restriction>
  </xs:simpleType>

  <xs:complexType name="MigrationRule">
    <xs:annotation>
      <xs:documentation>
        <![CDATA[
        A migration rule is an ordered set of scripts to load and execute in order to perform
        a migration of the data source of the underlying module.
        ]]>
      </xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element name="script" maxOccurs="unbounded">
        <xs:complexType>
          <xs:attribute name="name" type="xs:token" use="required"/>
          <xs:attribute name="type" type="ScriptType" use="required"/>
        </xs:complexType>
      </xs:element>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="CreationRule">
    <xs:annotation>
      <xs:documentation>
        <![CDATA[
        A migration rule dedicated to create the data source of the underlying module.
        ]]>
      </xs:documentation>
    </xs:annotation>
    <xs:complexContent>
      <xs:extension base="MigrationRule">
        <xs:attribute name="version" type="VersionID" use="required"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <xs:complexType name="UpgradeRule">
    <xs:annotation>
      <xs:documentation>
        <![CDATA[
        A migration rule dedicated to upgrade the data source of the underlying module from the
        version fromVersion to the next one.
        ]]>
      </xs:documentation>
    </xs:annotation>
    <xs:complexContent>
      <xs:extension base="MigrationRule">
        <xs:attribute name="fromVersion" type="VersionID" use="required"/>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

</xs:schema>