<?xml version="1.0" encoding="UTF-8"?>
<xs:schema 
xmlns:xs="http://www.w3.org/2001/XMLSchema" 
xmlns:vr="http://www.ivoa.net/xml/VOResource/v1.0" 
xmlns:vm="http://www.ivoa.net/xml/VOMetadata/v0.1" 
xmlns:tr="http://www.ivoa.net/xml/TAPRegExt/v1.0"
version="1.0"
targetNamespace="http://www.ivoa.net/xml/TAPRegExt/v1.0" 
elementFormDefault="unqualified" 
attributeFormDefault="unqualified" 
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.w3.org/2001/XMLSchema http://vo.ari.uni-heidelberg.de/docs/schemata/XMLSchema.xsd">
  <xs:annotation>
    <xs:appinfo>
      <vm:schemaName>TAPRegExt</vm:schemaName>
      <vm:schemaPrefix>xs</vm:schemaPrefix>
      <vm:targetPrefix>tr</vm:targetPrefix>
    </xs:appinfo>
    <xs:documentation>
    A description of the capabilities metadata for TAP services.
    </xs:documentation>
  </xs:annotation>
  <xs:import namespace="http://www.ivoa.net/xml/VOResource/v1.0"
  	schemaLocation="http://docs.g-vo.org/schemata/VOResource.xsd"/>
  <xs:complexType name="TableAccess">
    <xs:annotation>
      <xs:documentation>
      The capabilities of a TAP server.
      </xs:documentation>
      <xs:documentation>
      The capabilities attempt to define most issues that the
      TAP standard leaves to the implementors ("may", "should").
      </xs:documentation>
    </xs:annotation>
    <xs:complexContent>
      <xs:extension base="vr:Capability">
        <xs:sequence>

          <xs:element name="dataModel" type="tr:DataModelType"
            minOccurs="0" maxOccurs="unbounded">
            <xs:annotation>
              <xs:documentation>
              Identifier of IVOA-approved data model supported by the 
              service.
              </xs:documentation>
            </xs:annotation>
          </xs:element>

          <xs:element name="language" type="tr:Language"
            minOccurs="1" maxOccurs="unbounded">
            <xs:annotation>
              <xs:documentation>
              Language supported by the service.
              </xs:documentation>
            </xs:annotation>
          </xs:element>

          <xs:element name="outputFormat" type="tr:OutputFormat"
            minOccurs="1" maxOccurs="unbounded">
            <xs:annotation>
              <xs:documentation>
                Output format supported by the service.
              </xs:documentation>
            </xs:annotation>
          </xs:element>

          <xs:element name="uploadMethod" type="tr:UploadMethod"
            minOccurs="0" maxOccurs="unbounded">
            <xs:annotation>
              <xs:documentation>
                Upload method supported by the service.
              </xs:documentation>
              <xs:documentation>
                The absence of upload methods indicates
                that the service does not support uploads
                at all.
              </xs:documentation>
            </xs:annotation>
          </xs:element>

          <xs:element name="retentionPeriod" type="tr:TimeLimits"
            minOccurs="0" maxOccurs="1">
            <xs:annotation>
              <xs:documentation>
              Limits on the time between job creation and
              destruction time.
              </xs:documentation>
            </xs:annotation>
          </xs:element>

          <xs:element name="executionDuration" type="tr:TimeLimits"
            minOccurs="0" maxOccurs="1">
            <xs:annotation>
              <xs:documentation>
              Limits on executionDuration.
              </xs:documentation>
            </xs:annotation>
          </xs:element>

          <xs:element name="outputLimit" type="tr:DataLimits"
            minOccurs="0" maxOccurs="1">
            <xs:annotation>
              <xs:documentation>
              Limits on the size of data returned.
              </xs:documentation>
            </xs:annotation>
          </xs:element>

          <xs:element name="uploadLimit" type="tr:DataLimits"
            minOccurs="0" maxOccurs="1">
            <xs:annotation>
              <xs:documentation>
              Limits on the size of uploaded data.
              </xs:documentation>
            </xs:annotation>
          </xs:element>

            
        </xs:sequence>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <xs:complexType name="DALIInterface">
    <xs:annotation>
      <xs:documentation>
        An interface for a complex, multi-endpoint interfaces as
        regulated by DALI.
      </xs:documentation>
      <xs:documentation>
        In addition to the standard vr:Interface elements, DALIInterfaces
        have endpoints, listed by name; that name doubles as a path segment
        to append to the interface's access URL, yielding the URI at
        which the endpoint is operated.
      </xs:documentation>
    </xs:annotation>
    
    <xs:complexContent>
      <xs:extension base="vr:Interface">
        <xs:sequence>
          <xs:element name="endpoint" type="tr:Endpoint"
              minOccurs="0" maxOccurs="unbounded">
            <xs:annotation>
              <xs:documentation>
                An endpoint accessible through this interface.
              </xs:documentation>
            </xs:annotation>
          </xs:element>
        </xs:sequence>
      </xs:extension>
    </xs:complexContent>
  </xs:complexType>

  <xs:complexType name="Endpoint">
    <xs:annotation>
      <xs:documentation>
        An endpoint of a complex interface.
      </xs:documentation>
      <xs:documentation>
        An endpoint is characterised and addrssed by its name;
        they can further be defined through RDF triples.  This is a
        generic extension mechanism for endpoint-specific metadata,
        primarily intended for custom, vendor-specific extensions.
      </xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element name="name" type="xs:token"
          minOccurs="1" maxOccurs="1">
        <xs:annotation>
          <xs:documentation>
            The endpoint name, which is also the last component of the
            path of its URI.
          </xs:documentation>
          <xs:documentation>
            Names without dashes are reserved for IVOA use and are expected to
            work the same way on all services.  Well-known examples for
            such endpoint names include sync, async, and tables.
          </xs:documentation>
        </xs:annotation>
      </xs:element>

      <xs:element name="meta" type="tr:MetaTriple"
          minOccurs="0" maxOccurs="unbounded">
        <xs:annotation>
          <xs:documentation>
            Auxiliary information on this endpoint.
          </xs:documentation>
        </xs:annotation>
      </xs:element>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="MetaTriple">
    <xs:annotation>
      <xs:documentation>
        A container for an RDFa triple giving information related to
        an endpoint.
      </xs:documentation>
    </xs:annotation>
    <xs:simpleContent>
      <xs:extension base="xs:token">
        <xs:attribute name="about" type="xs:anyURI" use="optional">
          <xs:annotation>
            <xs:documentation>
              The subject of the statement.
            </xs:documentation>
            <xs:documentation>
              If missing, the endpoint itself is assumed as the subject.
            </xs:documentation>
          </xs:annotation>
        </xs:attribute>
        <xs:attribute name="property" type="xs:anyURI" use="required">
          <xs:annotation>
            <xs:documentation>
              The property of the statement.
            </xs:documentation>
            <xs:documentation>
              This is a reference to an RDF resource.  IVOA standards may define
              semantics for scheme-less URI; non-IVOA properties must use
              full URIs with at least scheme and authority; in this
              version, no vocab attributes are supported.
            </xs:documentation>
          </xs:annotation>
        </xs:attribute>
        <xs:attribute name="resource" type="xs:anyURI" use="optional">
          <xs:annotation>
            <xs:documentation>
              The object of the statement.
            </xs:documentation>
            <xs:documentation>
              If missing, the text content of the element is used as the
              object.
            </xs:documentation>
          </xs:annotation>
        </xs:attribute>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>

  <xs:complexType name="DataModelType">
    <xs:annotation>
      <xs:documentation>
        An IVOA defined data model, identified by an IVORN 
        intended for machine consumption and a short label
        intended for human comsumption.
      </xs:documentation>
    </xs:annotation>

    <xs:simpleContent>
      <xs:extension base="xs:token"> 
        <xs:attribute name="ivo-id" type="xs:anyURI" use="required">
          <xs:annotation>
            <xs:documentation>
            The IVOID of the data model.
            </xs:documentation>
          </xs:annotation>
        </xs:attribute>
      </xs:extension>    
    </xs:simpleContent>
  </xs:complexType>  

  <xs:complexType name="Language">
    <xs:annotation>
      <xs:documentation>
      A query language supported by the service.
      </xs:documentation>
      <xs:documentation>
      Each language element can describe one or more versions
      of a language.  Either name alone or name-version can be
      used as values for the server's LANG parameter.
      </xs:documentation>
    </xs:annotation>

    <xs:sequence>
      <xs:element name="name" type="xs:NCName">
        <xs:annotation>
          <xs:documentation>
          The name of the language without a version suffix.
          </xs:documentation>
        </xs:annotation>
      </xs:element>

      <xs:element name="version" type="tr:Version"
        minOccurs="1" maxOccurs="unbounded">
        <xs:annotation>
          <xs:documentation>
            A version of the language supported by the server.
          </xs:documentation>
        </xs:annotation>
      </xs:element>

      <xs:element name="description" type="xs:token"
        minOccurs="0">
        <xs:annotation>
          <xs:documentation>
          A short, human-readable description of the
          query language.
          </xs:documentation>
        </xs:annotation>
      </xs:element>

       <xs:element name="languageFeatures" type="tr:LanguageFeatureList" 
           minOccurs="0" maxOccurs="unbounded">
        <xs:annotation>
          <xs:documentation>
            Optional features of the query language, grouped by
            feature type.
          </xs:documentation>
          <xs:documentation>
            This includes listing user defined functions, geometry support,
            or similar concepts.
          </xs:documentation>
        </xs:annotation>
      </xs:element>
    </xs:sequence>
  </xs:complexType>  

  <xs:complexType name="Version">
    <xs:annotation>
      <xs:documentation>
      One version of the language supported by the service.
      </xs:documentation>
      <xs:documentation>
      If the service supports more than one version of the
      language, include multiple version elements.
      It is recommended that you use a version numbering
      scheme like MAJOR.MINOR in such a way that sorting
      by ascending character codes will leave the most
      recent version at the bottom of the list.
      </xs:documentation>
    </xs:annotation>

    <xs:simpleContent>
      <xs:extension base="xs:token">
        <xs:attribute name="ivo-id" type="xs:anyURI">
          <xs:annotation>
            <xs:documentation>
            An optional IVOID of the language.
            </xs:documentation>
            <xs:documentation>
              To more formally define a language supported by a service,
              a resource record for the language can be created, either
              centrally on the Registry of Registries or by other registry operators.  
              When such a record exists, the ivo-id attribute of language
              should point to it.
            </xs:documentation>
          </xs:annotation>
        </xs:attribute>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>

  <xs:complexType name="LanguageFeatureList">
    <xs:annotation>
      <xs:documentation>
        An enumeration of non-standard or non-mandatory features of 
        a specific type implemented by the language.
      </xs:documentation>
      <xs:documentation>
        A feature type is a language-dependent concept like 
        "user defined function", "geometry support", or possibly 
        "units supported".  A featureList gives all features of
        a given type applicable for the service.  Multiple featureLists
        are possible.

        All feature in a given list are of the same type.  This type
        is declared using the mandatory type attribute,
        the value of which will typically be an IVOID.
        To see values defined in TAPRegExt,
        retrieve the ivo://ivoa.net/std/TAPRegExt
        resource record and look for keys starting with "features-".
      </xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element name="feature" type="tr:LanguageFeature"
           minOccurs="0" maxOccurs="unbounded">
        <xs:annotation>
          <xs:documentation>
            A language feature of the type given by the
            type attribute.
          </xs:documentation>
        </xs:annotation>
      </xs:element>
    </xs:sequence>
    <xs:attribute name="type" type="xs:anyURI" 
        use="required">
      <xs:annotation>
        <xs:documentation>
          The type of the features given here.
        </xs:documentation>
        <xs:documentation>
          This is in general an IVOID.  TAPRegExt itself gives
          IVOIDs for defining user defined functions and geometry
          support.
        </xs:documentation>
      </xs:annotation>
    </xs:attribute>
  </xs:complexType>

  <xs:complexType name="LanguageFeature">
    <xs:annotation>
      <xs:documentation>
        A non-standard or non-mandatory feature implemented
        by the language..
      </xs:documentation>
    </xs:annotation>
    <xs:sequence>
      <xs:element name="form" type="xs:token">
        <xs:annotation>
          <xs:documentation>
            Formal notation for the language feature.
          </xs:documentation>
          <xs:documentation>
            The syntax for the content of this element is defined by the
            type attribute of its parent language list.
          </xs:documentation>
        </xs:annotation>
      </xs:element>
      <xs:element name="description" type="xs:string" minOccurs="0">
        <xs:annotation>
          <xs:documentation>
            Human-readable freeform documentation for the language feature.
          </xs:documentation>
        </xs:annotation>
      </xs:element>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="OutputFormat">
    <xs:annotation>
      <xs:documentation>
      An output format supported by the service.
      </xs:documentation>
      <xs:documentation>
			All TAP services must support VOTable output, with media types as 
      requested by the FORMAT parameter if applicable (cf.~section 2.7.1 
      of the TAP standard).

      The primary identifier for an output format is the RFC 2046 media
      type.  If you want to register an output format, you must
      use a media type (or make one up using the x- syntax), although
      the concrete media syntax is not enforced by the schema.

      For more detailed specification, an IVOID may be used.
      </xs:documentation>
    </xs:annotation>

    <xs:sequence>
      <xs:element name="mime" type="xs:token">
        <xs:annotation>
          <xs:documentation>
          The media type of this format.
          </xs:documentation>
          <xs:documentation>
          The format of this string is specified by RFC 2046.
          The service has to accept this string as a 
          value of the FORMAT parameter.
          </xs:documentation>
        </xs:annotation>
      </xs:element>

      <xs:element name="alias" type="xs:token"
        minOccurs="0" maxOccurs="unbounded">
        <xs:annotation>
          <xs:documentation>
          Other values of FORMAT ("shorthands") that make the service return 
          documents with the media type.
          </xs:documentation>
        </xs:annotation>
      </xs:element>
        
    </xs:sequence>
  
    <xs:attribute name="ivo-id" type="xs:anyURI">
      <xs:annotation>
        <xs:documentation>
        An optional IVOID of the output format.
        </xs:documentation>
        <xs:documentation>
          When the media type does not uniquely define the
          format (or a generic media type like application/octet-stream or
          text/plain is given), the IVOID can point to a key
          or StandardsRegExt document defining the format more
          precisely.  To see values defined in TAPRegExt,
          retrieve the ivo://ivoa.net/std/TAPRegExt
          resource record and look for keys starting with "output-".
        </xs:documentation>
      </xs:annotation>
    </xs:attribute>

  </xs:complexType>  

  <xs:complexType name="UploadMethod">
    <xs:annotation>
      <xs:documentation>
      An upload method as defined by IVOA.
      </xs:documentation>
      <xs:documentation>
      Upload methods are always identified by an IVOID.  
      Descriptions can be obtained by dereferencing this
      IVOID.  To see values defined in TAPRegExt,
      retrieve the ivo://ivoa.net/std/TAPRegExt
      resource record and look for keys starting with "upload-".

      You can register custom upload methods, but you must use the
      standard IVOIDs for the upload methods defined in the TAP
      specification.
      </xs:documentation>
    </xs:annotation>

    <xs:complexContent>
      <xs:restriction base="xs:anyType">
        <xs:attribute name="ivo-id" type="xs:anyURI">
          <xs:annotation>
            <xs:documentation>
            The IVOID of the upload method.
            </xs:documentation>
          </xs:annotation>
        </xs:attribute>
      </xs:restriction>
    </xs:complexContent>
  </xs:complexType>


  <xs:complexType name="TimeLimits">
    <xs:annotation>
      <xs:documentation>
      Time-valued limits, all values given in seconds.
      </xs:documentation>
    </xs:annotation>

    <xs:sequence>
      <xs:element name="default" type="xs:integer"
        minOccurs="0" maxOccurs="1">
        <xs:annotation>
          <xs:documentation>
          The value of this limit for newly-created jobs, given in seconds.
          </xs:documentation>
        </xs:annotation>
      </xs:element>
      <xs:element name="hard" type="xs:integer"
        minOccurs="0" maxOccurs="1">
        <xs:annotation>
          <xs:documentation>
          The value this limit cannot be raised above, given in seconds.
          </xs:documentation>
        </xs:annotation>
      </xs:element>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="DataLimits">
    <xs:annotation>
      <xs:documentation>
      Limits on data sizes, given in rows or bytes.
      </xs:documentation>
    </xs:annotation>

    <xs:sequence>
      <xs:element name="default" type="tr:DataLimit"
        minOccurs="0" maxOccurs="1">
        <xs:annotation>
          <xs:documentation>
          The value of this limit for newly-created jobs.
          </xs:documentation>
        </xs:annotation>
      </xs:element>
      <xs:element name="hard" type="tr:DataLimit"
        minOccurs="0" maxOccurs="1">
        <xs:annotation>
          <xs:documentation>
          The value this limit cannot be raised above.
          </xs:documentation>
        </xs:annotation>
      </xs:element>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="DataLimit">
    <xs:annotation>
      <xs:documentation>
      A limit on some data size, either in rows or in bytes.
      </xs:documentation>
    </xs:annotation>

    <xs:simpleContent>
      <xs:extension base="xs:integer">
        <xs:attribute name="unit" use="required">
          <xs:annotation>
            <xs:documentation>
            The unit of the limit specified.
            </xs:documentation>
          </xs:annotation>
          <xs:simpleType>
            <xs:restriction base="xs:token">
              <xs:enumeration value="byte"/>
              <xs:enumeration value="row"/>
            </xs:restriction>
          </xs:simpleType>
        </xs:attribute>
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>

</xs:schema>  
