<?xml version="1.0"?>
<xsd:schema
   targetNamespace="http://www.opengis.net/wfs"
   xmlns:xsd="http://www.w3.org/2001/XMLSchema"
   xmlns:gml="http://www.opengis.net/gml"
   xmlns:ogc="http://www.opengis.net/ogc"
   xmlns:wfs="http://www.opengis.net/wfs"
   elementFormDefault="qualified">

   <!-- ==============================================================
        Includes and Imports
        ============================================================== -->
   <xsd:include schemaLocation="WFS-basic.xsd"/>
   <xsd:import namespace="http://www.opengis.net/gml"
               schemaLocation="../../gml/2.1.2/feature.xsd"/>
   <xsd:import namespace="http://www.opengis.net/ogc"
               schemaLocation="../../filter/1.0.0/filter.xsd"/>

   <!-- ==============================================================
         REQUEST MESSAGES
         ============================================================== -->
   <xsd:element name="GetFeatureWithLock" type="wfs:GetFeatureWithLockType">
      <xsd:annotation>
         <xsd:documentation>
            This is the root element for the GetFeatureWithLock request.
            The GetFeatureWithLock operation performs identically to a
            GetFeature request except that the GetFeatureWithLock request
            locks all the feature instances in the result set and returns
            a lock identifier to a client application in the response.
         </xsd:documentation>
      </xsd:annotation>
   </xsd:element>
   <xsd:element name="LockFeature" type="wfs:LockFeatureType">
      <xsd:annotation>
         <xsd:documentation>
            This is the root element for a LockFeature request.
            The LockFeature request can be used to lock one or
            more feature instances.
         </xsd:documentation>
      </xsd:annotation>
   </xsd:element>
   <xsd:element name="Transaction" type="wfs:TransactionType">
      <xsd:annotation>
         <xsd:documentation>
            This is the root element for a Transaction request.
            A transaction request allows insert, update and 
            delete operations to be performed to create, change
            or remove feature instances.
         </xsd:documentation>
      </xsd:annotation>
   </xsd:element>

   <!-- ==============================================================
         RESPONSE MESSAGES
         ============================================================== -->
   <xsd:element name="WFS_LockFeatureResponse"
                type="wfs:WFS_LockFeatureResponseType">
      <xsd:annotation>
         <xsd:documentation>
            The WFS_LockFeatureResponse element contains a report
            about the completion status of a LockFeature request.
         </xsd:documentation>
      </xsd:annotation>
   </xsd:element>
   <xsd:element name="WFS_TransactionResponse"
                type="wfs:WFS_TransactionResponseType">
      <xsd:annotation>
         <xsd:documentation>
            The WFS_TransactionResponse element contains a report
            about the completion status of a Transaction operation.  
         </xsd:documentation>
      </xsd:annotation>
   </xsd:element>

   <!-- ==============================================================
         COMMON ATTRIBUTE DOCUMENTATION
         ============================================================== 
         EXPIRY:
            The expiry attribute value is specified in minutes. It
            indicates how long a Web Feature Service should wait to
            receive a request from the client application that locked
            the feature instances.  If the specified time elapses and
            no request has been received by a Web Feature Service that
            references the lockId given to the client application, then
            the locks maintained by the Web Feature Service shall be
            released and the lockId that references the locked features
            shall now be invalid.  If the expiry attribute is not specified,
            then the feature instances shall be locked indefinitely and the
            intervention of an administrator may be required to release
            the locks. -->

   <!-- ==============================================================
         TYPES
         ============================================================== -->
   <!-- GETFEATUREWITHLOCK -->
   <xsd:complexType name="GetFeatureWithLockType">
      <xsd:annotation>
         <xsd:documentation>
            A GetFeatureWithLock request operates identically to a
            GetFeature request expect that it attempts to lock the
            feature instances in the result set and includes a lock
            identifier in its response to a client.  A lock identifier
            is an identifier generated by a Web Feature Service that 
            a client application can use, in subsequent operations,
            to reference the locked set of feature instances.
         </xsd:documentation>
      </xsd:annotation>
      <xsd:sequence>
         <xsd:element ref="wfs:Query" maxOccurs="unbounded"/>
      </xsd:sequence>
      <xsd:attribute name="version"
                     type="xsd:string" use="required" fixed="1.0.0"/>
      <xsd:attribute name="service"
                     type="xsd:string" use="required" fixed="WFS"/>
      <xsd:attribute name="handle"
                     type="xsd:string" use="optional"/>
      <xsd:attribute name="expiry"
                     type="xsd:positiveInteger" use="optional"/>
      <xsd:attribute name="outputFormat"
                     type="xsd:string" use="optional" default="GML2"/>
      <xsd:attribute name="maxFeatures"
                     type="xsd:positiveInteger" use="optional"/>
   </xsd:complexType>
   <!-- LOCKFEATURE -->
   <xsd:complexType name="LockFeatureType">
      <xsd:annotation>
         <xsd:documentation>
            This type defines the LockFeature operation.  The LockFeature
            element contains one or more Lock elements that define
            which features of a particular type should be locked.  A lock
            identifier (lockId) is returned to the client application which
            can be used by subsequent operations to reference the locked
            features.
         </xsd:documentation>
      </xsd:annotation>
      <xsd:sequence>
         <xsd:element name="Lock" type="wfs:LockType" maxOccurs="unbounded">
            <xsd:annotation>
               <xsd:documentation>
                  The lock element is used to indicate which feature 
                  instances of particular type are to be locked.
               </xsd:documentation>
            </xsd:annotation>
         </xsd:element>
      </xsd:sequence>
      <xsd:attribute name="version"
                     type="xsd:string" use="required" fixed="1.0.0"/>
      <xsd:attribute name="service"
                     type="xsd:string" use="required" fixed="WFS"/>
      <xsd:attribute name="expiry"
                     type="xsd:positiveInteger" use="optional"/>
      <xsd:attribute name="lockAction"
                     type="wfs:AllSomeType" use="optional">
         <xsd:annotation>
            <xsd:documentation>
               The lockAction attribute is used to indicate what
               a Web Feature Service should do when it encounters
               a feature instance that has already been locked by
               another client application.

               Valid values are ALL or SOME.

               ALL means that the Web Feature Service must acquire
               locks on all the requested feature instances.  If it
               cannot acquire those locks then the request should
               fail.  In this instance, all locks acquired by the
               operation should be released.
 
               SOME means that the Web Feature Service should lock
               as many of the requested features as it can.
            </xsd:documentation>
         </xsd:annotation>
      </xsd:attribute>
   </xsd:complexType>
   <xsd:complexType name="LockType">
      <xsd:annotation>
         <xsd:documentation>
            This type defines the Lock element.  The Lock element
            defines a locking operation on feature instances of 
            a single type. An OGC Filter is used to constrain the
            scope of the operation.  Features to be locked can be
            identified individually by using their feature identifier
            or they can be locked by satisfying the spatial and 
            non-spatial constraints defined in the filter.
         </xsd:documentation>
      </xsd:annotation>
      <xsd:sequence>
         <xsd:element ref="ogc:Filter" minOccurs="0" maxOccurs="1"/>
      </xsd:sequence>
      <xsd:attribute name="handle" 
                     type="xsd:string" use="optional"/>
      <xsd:attribute name="typeName" 
                     type="xsd:QName" use="required"/>
   </xsd:complexType>
   <!-- TRANSACTION -->
   <xsd:complexType name="TransactionType">
      <xsd:annotation>
         <xsd:documentation>
            The TranactionType defines the Transaction operation.  A
            Transaction element contains one or more Insert, Update
            Delete and Native elements that allow a client application
            to create, modify or remove feature instances from the 
            feature repository that a Web Feature Service controls.
         </xsd:documentation>
      </xsd:annotation>
      <xsd:sequence>
         <xsd:element ref="wfs:LockId" minOccurs="0">
            <xsd:annotation>
               <xsd:documentation>
                  In order for a client application to operate upon locked
                  feature instances, the Transaction request must include
                  the LockId element.  The content of this element must be
                  the lock identifier the client application obtained from
                  a previous GetFeatureWithLock or LockFeature operation.

                  If the correct lock identifier is specified the Web
                  Feature Service knows that the client application may
                  operate upon the locked feature instances.

                  No LockId element needs to be specified to operate upon
                  unlocked features.
               </xsd:documentation>
            </xsd:annotation>
         </xsd:element>
         <xsd:choice minOccurs="0" maxOccurs="unbounded">
            <xsd:element ref="wfs:Insert"/>
            <xsd:element ref="wfs:Update"/>
            <xsd:element ref="wfs:Delete"/>
            <xsd:element ref="wfs:Native"/>
         </xsd:choice>
      </xsd:sequence>
      <xsd:attribute name="version"
                     type="xsd:string" use="required" fixed="1.0.0"/>
      <xsd:attribute name="service"
                     type="xsd:string" use="required" fixed="WFS"/>
      <xsd:attribute name="handle"
                     type="xsd:string" use="optional"/>
      <xsd:attribute name="releaseAction"
                     type="wfs:AllSomeType" use="optional">
         <xsd:annotation>
            <xsd:documentation>
               The releaseAction attribute is used to control how a Web
               Feature service releases locks on feature instances after
               a Transaction request has been processed.

               Valid values are ALL or SOME.

               A value of ALL means that the Web Feature Service should
               release the locks of all feature instances locked with the
               specified lockId, regardless or whether or not the features
               were actually modified.

               A value of SOME means that the Web Feature Service will 
               only release the locks held on feature instances that 
               were actually operated upon by the transaction.  The lockId
               that the client application obtained shall remain valid and
               the other, unmodified, feature instances shall remain locked.
               If the expiry attribute was specified in the original operation 
               that locked the feature instances, then the expiry counter
               will be reset to give the client application that same amount
               of time to post subsequent transactions against the locked
               features.
            </xsd:documentation>
         </xsd:annotation>
      </xsd:attribute>
   </xsd:complexType>
   <xsd:element name="LockId" type="xsd:string">
      <xsd:annotation>
         <xsd:documentation>
            The LockId element contains the value of the lock identifier
            obtained by a client application from a previous GetFeatureWithLock
            or LockFeature request.
         </xsd:documentation>
      </xsd:annotation>
   </xsd:element>
   <xsd:element name="Insert" type="wfs:InsertElementType">
      <xsd:annotation>
         <xsd:documentation>
            The Insert element is used to indicate that the Web Feature
            Service should create a new instance of a feature type.  The
            feature instance is specified using GML2 and one or more 
            feature instances to be created can be contained inside the
            Insert element.
         </xsd:documentation>
      </xsd:annotation>
   </xsd:element>
   <xsd:complexType name="InsertElementType">
      <xsd:sequence>
         <xsd:element ref="gml:_Feature" maxOccurs="unbounded"/>
      </xsd:sequence>
      <xsd:attribute name="handle" type="xsd:string" use="optional"/>
   </xsd:complexType>
   <xsd:element name="Update" type="wfs:UpdateElementType">
      <xsd:annotation>
         <xsd:documentation>