RXS_Parse()

This subprocedure is used to set up XML parsing. Use of this subprocedure requires an XML handler subprocedure to also be written.

The events recognized by the XML parser are:

Event	Format	Example
Element Begin	`>`	`Request>`
Element Content	`/`	`Request/Item/`
Element End	`/>`	`Request/>`
Attribute	`@`	`Request/Item@Attribute`

The Element Content and Attribute events will return data, which can be retrieved with RXS_STR().

Subprocedure Prototype

IBM i 6.1+

     D RXS_Parse...
     D                 PR                  Extproc('RXS_Parse')

     D   Input                             Like(RXS_Var16Mv_t)
     D                                     Options(*Varsize)

Holds the XML data to be passed to the parsing subprocedure(s). Will be ignored if the Stmf subfield of the DS parameter is set.

     D   ParseDS                           Likeds(RXS_ParseDS_t)

Holds a RXS_ParseDS_t data structure which controls how RXS_Parse() functions.

Example 1: Simple Parse

      *--------------------------------------------------------------
      * This example parses a simple XML structure stored in the field
      * 'XML' and stores the data contained in nodes <Node1> and <Node2>
      * in the corresponding global fields.
      *
      * At a high level, the XML is passed into the XmlHandler() 
      * subprocedure in small chunks. Then, a SELECT block is used to
      * detect whether or not the current chunk of XML matches one
      * you'd like to handle. If it does, you can extract the data from
      * an element of attribute using RXS_STR().
      *
      * Once the XML has been entirely passed through XmlHander(), control
      * returns to the main part of the program.
      *--------------------------------------------------------------
     H DFTACTGRP(*NO) BNDDIR('RXSBND') ACTGRP(*CALLER)

      /copy QRPGLECPY,RXSCB

     D XmlHandler      PR
     D  pType                        10A   Value
     D  pXPath                     1024A   Value Varying
     D  pData                          *   Value
     D  pDataLen                     10I 0 Value

     D ParseDS         DS                  LikeDS(RXS_ParseDS_t)
     D                                     Inz(*LikeDS)
     D XML             S                   Like(RXS_Var64Kv_t)
     D Node1           S                   Like(RXS_Var1Kv_t)
     D Node2           S                   Like(RXS_Var1Kv_t)
      /free
        XML = '<?xml version="1.0" encoding="utf-8"?>' +
         '<Root><Node1>Hello</Node1><Node2>World</Node2></Root>';

        reset ParseDS;
        ParseDS.GlobalHandler = %Paddr( XmlHandler );
        RXS_Parse( XML : ParseDS );

        RXS_JobLog( 'Node 1: %s' : Node1 );
        RXS_JobLog( 'Node 2: %s' : Node2 );

        *INLR = *ON;
      /end-free

     P XmlHandler      B
     D XmlHandler      PI
     D  pType                        10A   Value
     D  pXPath                     1024A   Value Varying
     D  pData                          *   Value
     D  pDataLen                     10I 0 Value
      /free
        select;
          when pXPath = '/Root/Node1/';
            Node1 = RXS_STR( pData : pDataLen );
          when pXPath = '/Root/Node2/';
            Node2 = RXS_STR( pData : pDataLen );
        endsl;
      /end-free
     P                 E

Example 1: Simple Parse

      *--------------------------------------------------------------
      * This example parses a simple XML structure stored in the field
      * 'XML' and stores the data contained in nodes <Node1> and <Node2>
      * in the corresponding global fields.
      *
      * At a high level, the XML is passed into the XmlHandler() 
      * subprocedure in small chunks. Then, a SELECT block is used to
      * detect whether or not the current chunk of XML matches one
      * you'd like to handle. If it does, you can extract the data from
      * an element of attribute using RXS_STR().
      *
      * Once the XML has been entirely passed through XmlHander(), control
      * returns to the main part of the program.
      *--------------------------------------------------------------
     H DFTACTGRP(*NO) BNDDIR('RXSBND') ACTGRP(*CALLER)

      /define RXSV6R1
      /copy QRPGLECPY,RXSCB

     D XmlHandler      PR
     D  pType                        10A   Value
     D  pXPath                     1024A   Value Varying
     D  pData                          *   Value
     D  pDataLen                     10I 0 Value

     D ParseDS         DS                  LikeDS(RXS_ParseDS_t)
     D                                     Inz(*LikeDS)
     D XML             S                   Like(RXS_Var64Kv_t)
     D Node1           S                   Like(RXS_Var1Kv_t)
     D Node2           S                   Like(RXS_Var1Kv_t)
      /free
        XML = '<?xml version="1.0" encoding="utf-8"?>' +
         '<root><node1>Hello</node1><node2>World</node2></root>';

        reset ParseDS;
        ParseDS.GlobalHandler = %Paddr( XmlHandler );
        RXS_Parse( XML : ParseDS );

        RXS_JobLog( 'Node 1: %s' : Node1 );
        RXS_JobLog( 'Node 2: %s' : Node2 );

        *INLR = *ON;
      /end-free

     P XmlHandler      B
     D XmlHandler      PI
     D  pType                        10A   Value
     D  pXPath                     1024A   Value Varying
     D  pData                          *   Value
     D  pDataLen                     10I 0 Value
      /free
        select;
          when pXPath = '/root/node1/';
            RXS_STR( Node1 : pData : pDataLen );
          when pXPath = '/root/node2/';
            RXS_STR( Node2 : pData : pDataLen );
        endsl;
      /end-free
     P                 E

Data Structures

RXS_ParseDS_t

`D RXS_ParseDS_t DS Qualified Template Inz`
`D ReturnedErrorInfo... D Like(RXS_ReturnedErrorInfoDS_t) Inz`
`D OnErrorMessageType... D 10I 0`
`D GlobalHandler... D * Procptr`	Holds a PROCPTR to an XmlHandler subprocedure used to handle all possible XML events.
`D ElementContentHandler... D * Procptr`	Holds a PROCPTR to an XmlHandler subprocedure which will only respond to XML content events.
`D ElementBeginHandler... D * Procptr`	Holds a PROCPTR to an XmlHandler subprocedure which will only respond to XML begin events.
`D ElementEndHandler... D * Procptr`	Holds a PROCPTR to an XmlHandler subprocedure which will only respond to XML end events.
`D AttributeHandler... D * Procptr`	Holds a PROCPTR to an XmlHandler subprocedure which will only respond to XML attribute events.
`D IncludeNamespaces... D N`	Controls whether namespaces are factored into XML parsing - if RXS_NO, they will be ignored.
`D InputCcsid... D 10I 0`	Specifies the CCSID of the XML being parsed.
`D OutputCcsid... D 10I 0`	Specifies the CCSID the parsed data will be converted to.
`D Stmf... D Like(RXS_Var1Kv_t)`	Specifies an IFS path to an XML file to parse instead of the Input parm.

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