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Prétraiter un schéma pour fusionner des schémas inclus

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S’applique à : SQL Server Azure SQL Database Azure SQL Managed Instance

L’élément W3C XSD include assure la prise en charge de la modularité des schémas, selon laquelle un schéma XML peut être partitionné en plusieurs fichiers physiques. SQL Server ne prend actuellement pas en charge cet élément. Les schémas XML incluant cet élément seront rejetés par le serveur.

En guise de solution, les schémas XML comportant la directive <xsd:include> peuvent être prétraités de façon à copier et à fusionner le contenu des schémas inclus en un seul schéma à charger sur le serveur. Vous pouvez utiliser le code C# suivant pour le prétraitement. Les commentaires dans la première partie du code fournissent des informations sur son utilisation.

// XSD Schema Include Normalizer
// To compile:
// csc filename.cs
//
// How to use:
//
// Arguments: [-q] input.xsd [output.xsd]
//
// input.xsd       - file to normalize
// output.xsd      - file to output, default is console
// -q              - quiet
//
// Example:
//
// filename.exe schema.xsd
//
using System;
using System.Xml;
using System.Xml.Schema;
using System.IO;
using System.Collections;
public class XsdSchemaNormalizer
{
    private static bool NormalizeXmlSchema( String url, TextWriter writer )
    {
   try {
       XmlTextReader txtRead = new XmlTextReader( url );
       XmlSchema sch = XmlSchema.Read( txtRead, null );

       // Compiling Schema
       sch.Compile(null);

       XmlSchema outSch =
      XmlSchemaIncludeNormalizer.BuildIncludeFreeXmlSchema( sch);

       outSch.Write( writer );
   } catch ( Exception e ) {
       Console.WriteLine(e.ToString());
       return false;
   }
   return true;
    }
    public static void usage()
    {
   Console.WriteLine("Arguments: [-q] [-v] input.xsd [output.xsd]\n");
   Console.WriteLine("input.xsd       - file to normalize");
   Console.WriteLine("output.xsd      - file to output, default is console");
   Console.WriteLine("-q              - quiet");
    }
    public static void Main(String []args)
    {
   if( args.GetLength(0) < 1 ) {
       usage();
       return;
   }
   int argi = 0;
   bool quiet = false;
   if( args[argi] == "-q" ) {
       quiet = true;
            argi++;
   }

   if( argi == args.GetLength(0) )
   {
       usage();
       return;
   }

   String url = args[argi];

   if( !quiet )
       Console.WriteLine("Loading Schema: " + url);

   if( argi < ( args.GetLength(0) - 1 ) )
   {
       if( !quiet )
      Console.WriteLine("Outputing to file: " + args[argi+1]);

       StreamWriter output =
      new StreamWriter( new FileStream(args[argi+1], FileMode.Create ));

       NormalizeXmlSchema( url, output);
   }
   else
   {
       NormalizeXmlSchema( url, Console.Out);
   }

    }
}

// A class to remove all <include> from a Xml Schema
//
public class XmlSchemaIncludeNormalizer
{
    // Takes as input a XmlSchema which has includes in it
    // and the schema location uri of that XmlSchema
    //
    // Returns a "preprocessed" form of XmlSchema without any
    // includes. It still retains imports though. Also, it does
    // not propagate unhandled attributes
    //
    // It can throw any exception
    public static XmlSchema BuildIncludeFreeXmlSchema( XmlSchema inSch )
    {
   XmlSchema outSch = new XmlSchema();

   AddSchema( outSch, inSch );

   return outSch;
    }

    // Adds everything in the second schema minus includes to
    // the first schema
    //
    private static void AddSchema( XmlSchema outSch, XmlSchema add)
    {
   outSch.AttributeFormDefault = add.AttributeFormDefault;
   outSch.BlockDefault = add.BlockDefault;
   outSch.ElementFormDefault = add.ElementFormDefault;
   outSch.FinalDefault = add.FinalDefault;
   outSch.Id = add.Id;
   outSch.TargetNamespace = add.TargetNamespace;
   outSch.Version = add.Version;

   AddTableToSchema( outSch, add.AttributeGroups );
   AddTableToSchema( outSch, add.Attributes );
   AddTableToSchema( outSch, add.Elements );
   AddTableToSchema( outSch, add.Groups );
   AddTableToSchema( outSch, add.Notations );
   AddTableToSchema( outSch, add.SchemaTypes );

   // Handle includes as a special case
   for( int i = 0; i < add.Includes.Count; i++ )
   {
       if( ! ( add.Includes[i] is XmlSchemaInclude) )
      outSch.Includes.Add( add.Includes[i] );
   }
    }

    // Adds all items in the XmlSchemaObjectTable to the specified XmlSchema
    //
    private static void AddTableToSchema( XmlSchema outSch,
                 XmlSchemaObjectTable table )
    {
   IDictionaryEnumerator e = table.GetEnumerator();

   while( e.MoveNext() )
   {
       outSch.Items.Add( (XmlSchemaObject)e.Value );
   }
    }
}

Test de l'outil du préprocesseur

Vous pouvez utiliser les schémas XSD suivants pour tester l'outil du préprocesseur :

books_common.xsd

<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"
     xmlns="bookstore-schema"
     elementFormDefault="qualified" >
  <xsd:element name="publisher" type="xsd:string"/>
</xsd:schema>

books.xsd

<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"
     xmlns="bookstore-schema"
     elementFormDefault="qualified"
     targetNamespace="bookstore-schema">
  <xsd:include id="books_common" schemaLocation="books_common.xsd"/>
  <xsd:element name="bookstore" type="xsd:string" />
</xsd:schema>

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