Simple Transformation for XML in ABAP - Part III & some JSON on the side

This is just to explain a bit further on one of my comments from the earlier XML related post : Generate Simple Transformation for XML in ABAP - Part II.

There were a few questions regarding transforming ABAP ITABs with deep structures to XML and setting encoding ( other than default UTF-8 ) for the output XML etc.


Initial steps are similar to the example in my last XML related posts.

1. For this example, a standard table type with complex structure is used. Accordingly you can create a ST program using editor :
   
   
   
   • 
     
2. Generated ST Code [ Z_TEST_RAM ] is as below:
   
   

   <tt:transform xmlns:ddic="http://www.sap.com/abapxml/types/dictionary" xmlns:def="http://www.sap.com/abapxml/types/defined" xmlns:tt="http://www.sap.com/transformation-templates">
     <tt:root name="LDAP_TABLE" type="ddic:LDAPALTAB">
     <tt:template>
       <ldap_attributes>
         <tt:loop name="XALIAS0" ref=".LDAP_TABLE">
           <ldap_attribute>
             <name tt:value-ref="NAME">
             <vals>
               <tt:loop ref="VALS">
                 <value tt:value-ref="$REF.VAL">
               </value></tt:loop>
             </vals>
           </name></ldap_attribute>
         </tt:loop>
       </ldap_attributes>
     </tt:template>
   </tt:root></tt:transform>
   
   

3. ABAP Sample Code is as below :
   

    REPORT z_test_ram_xml.
   
   * complex structure example
   DATA : lt_itab TYPE ldapaltab,
   wa_itab LIKE LINE OF lt_itab ,
   lt_val TYPE valtabc,
   wa_val LIKE LINE OF lt_val .
   
   DATA: gv_xml_xstring TYPE xstring.
   DATA: gv_final_xml_xstring TYPE xstring.
   
   * <<< Populate Example data in complex struture itab
   wa_itab-name = 'header1'.
   
   wa_val-val = 'Hi'.
   APPEND wa_val TO wa_itab-vals.
   wa_val-val = 'How r you'.
   APPEND wa_val TO wa_itab-vals.
   
   APPEND wa_itab TO lt_itab.
   *>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
   * This is the main ST call.
   CALL TRANSFORMATION z_test_ram
   SOURCE ldap_table = lt_itab[]
   RESULT XML gv_xml_xstring.
   *>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
   * Now a Bit of cheating - to get the encoding we'll use standard XSLT ID
   * rather than ST - not required if you need Default UTF-8 from ST
   
   DATA :go_ixml TYPE REF TO if_ixml,
   go_stream_factory TYPE REF TO if_ixml_stream_factory,
   go_encoding TYPE REF TO if_ixml_encoding,
   go_resstream TYPE REF TO if_ixml_ostream.
   
   CONSTANTS: gc_encoding TYPE string VALUE 'UTF-16'. "or UTF-8 etc.
   
   go_ixml = cl_ixml=>create( ).
   go_stream_factory = go_ixml->create_stream_factory( ).
   go_encoding = go_ixml->create_encoding( character_set = gc_encoding byte_order = 0 ).
   go_resstream = go_stream_factory->create_ostream_XSTRING( gv_final_xml_xstring ).
   
   CALL METHOD go_resstream->set_encoding( go_encoding ).
   
   CALL TRANSFORMATION ID
   SOURCE XML gv_xml_xstring
   RESULT XML go_resstream.
   
   cl_salv_data_services=>download_xml_to_file(
   filename = 'C:\z_test_ram_xml_file.xml'
   xcontent = gv_final_xml_xstring ).
   
   

   
   
4. Downloaded XML with encoding set as "UTF-16" is as below:
   

   <?xml version="1.0" encoding="UTF-16"?>
   <LDAP_ATTRIBUTES>
    <LDAP_ATTRIBUTE>
     <NAME>header1</NAME>
      <VALS>
       <VALUE>Hi</VALUE>
       <VALUE>How r you</VALUE>
      </VALS>
    </LDAP_ATTRIBUTE>
   </LDAP_ATTRIBUTES>

---

By the way, I was experimenting with an XML to JSON converter( rather JSONML ) that is compatible with XSLT-1.0 hence it can be used with ABAP XSLT . I've not tested it properly yet but just to add some information: The XSLT is written by @bramstein and the code can be taken from here . Some details are on this can be found here. Steps are as below :

1. Created an XSLT program in XSLT_TOOL with Name(ID)  Z_RAM_TEST_XSLT_JSON .
• For the XSLT, get the code from here .
• Just changed a few lines due to some syntax issue, from this:
  

  <xsl:when test="(normalize-space($value) ne $value or string(number($value)) = 'NaN' or (substring($value , string-length($value), 1) = '.') or (substring($value, 1, 1) = '0') and not($value = '0')) and not($value = 'false') and not($value = 'true') and not($value = 'null')">
      <xsl:text>"</xsl:text>
      <xsl:call-template name="encode">
       <xsl:with-param name="input" select="$value"/>
      </xsl:call-template>
      <xsl:text>"</xsl:text>
     </xsl:when>
  

• To :
  

  <xsl:when test="(normalize-space($value) != $value or string(number($value)) = 'NaN' or (substring($value , string-length($value), 1) = '.')
                            or (substring($value, 1, 1) = '0') and not($value = '0'))
                            and not($value = 'false')
                            and not($value = 'true') and not($value = 'null')">
      <xsl:text>"</xsl:text>
      <xsl:call-template name="encode">
       <xsl:with-param name="input" select="$value"/>
      </xsl:call-template>
      <xsl:text>"</xsl:text>
     </xsl:when>
  

2. Added following piece of code at the end of the ABAP program (z_test_ram_xml) :
   [ Note that it might work directly from from ABAP Itab to JSON but there were some unwanted asx:abap tags appearing on the first line. That can be sorted out though. ]
   

    *<<<< Convert the output XML to JSON using XSLT
     DATA : gv_json_string TYPE STRING.
       CALL TRANSFORMATION  Z_RAM_TEST_XSLT_JSON 
       SOURCE XML gv_final_xml_xstring
   *    SOURCE ldap_table = lt_itab[]
       RESULT XML gv_json_string.
   
     WRITE : gv_json_string.
   
   

3. Resultant JSONML is as below :
   

   ["LDAP_ATTRIBUTES",["LDAP_ATTRIBUTE",["NAME","header1"],["VALS",["VALUE","Hi"],["VALUE","How r you"]]]]
   

Warning : Please don't use above approach for any productive program without proper testing.  If you are looking for an ABAP/JSON library, for production use, then I would suggest to check ABAP JSON Library by Uwe Fetzer @se38 on SDN. Also just wanted to mention that Blogger's comment-section does not accept XML/HTML code hence you may need to escape any code before posting it in comments. [ Hint : search for "escape html tool online" in Google ]

Updated on 27/01/2013 :

Please refer to Horst Keller's Blog Post on SCN
Basically, you no longer need to try so much for JSON<->ABAP transformation as with new Releases 7.02 and 7.03/7.31 (Kernel-patch 116) JSON is supported natively in ABAP. Enjoy!.. and I hope you understand that these little improvements are big enablers :)