· Nov 23, 2023

Conversion from %Stream.GlobalBinary to %CharacterStream


I'm receiving in one of our interface a XML file as a %Stream.GlobalBinary, and in the source Application that produces this XML file, the user sometimes add a special character that force the XML file to have the header encoding to UTF-8, instead of ISO-8859-1 : 

<?xml version="1.0" encoding="UTF8"?> 

When my current interface tries to convert the %Stream.GlobalBinary into  %XML.XPATH.Document to this exceptional UTF8 header encoding of the XML file : 

Set tSC=##class(%XML.XPATH.Document).CreateFromStream(stream,.tDoc)  --> contains exceptionally UTF8 encoding

I have the following bug that blocks the whole interface : 

invalid byte 'd' at position 2 of a 3-bytes sequence in at line 1 offset 39 (method zCreateFromStream)

So the idea I got is to create the following method I'm developping that forces to change the encoding to ISO-8859-1 of the XML file through the method ChangeXMLStreamEncoding : 

Method CheckANSIXMLHeader(pStream As %Stream.GlobalBinary) As %Stream.GlobalBinary

#dim inputCharStream As %CharacterStream
#dim outputCharStream As %CharacterStream
#dim outputGlobalBinStream As %Stream.GlobalBinary Set tSC = $$$OK

//first convert %Stream.GlobalBinary to %CharacterStream back    
    Set outputCharStream = ##class(Ens.Util.XML.Reader).ChangeXMLStreamEncoding(inputCharStream, "ISO-8859-1", , tSC)
//finally convert %CharacterStream back to %Stream.GlobalBinary
    Quit outputGlobalBinStream

This method ChangeXMLStreamEncoding  uses %CharacterStream only.

So my problem is that I don't know how to convert %Stream.GlobalBinary to %CharacterStream, and vice-versa

Could you tell me how to perform such conversion ? 


Thanks a lot

Frédéric Donnet-Monay, integrator, Centre Hospitalier Universitaire Vaud, Lausanne, Switzerland

Product version: IRIS 2022.1
$ZV: IRIS for UNIX (Red Hat Enterprise Linux 9 for x86-64) 2022.1.3 (Build 668U) Fri Apr 7 2023 12:41:06 EDT [HealthConnect:3.5.0-1.m1] [HealthConnect:3.5.0-1.m1]
Discussion (6)3
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I'm not sure I understand your issue right, my understanding is that you receive an XML declared as UTF-8 that contains ISO-8859-1 characters.

If so, you can convert the encoding of the stream content using something like:

/// Convert the encoding of the content of a stream to UTF-8.
/// If OutStream is not passed (of any %Stream.* class), then a new %Stream.GlobalBinary is returned.
/// Note that OutStream IS NOT SAVED on exit
ClassMethod ConvertStreamToUTF8(InStream As %Stream.Object, ByRef OutStream As %Stream.Object = {##class(%Stream.GlobalBinary).%New()}) As %Status
	Set sc=$$$OK
	Set MaxRead=$$$MaxLocalLength\2 ; to be safe
	Try {
		While 'InStream.AtEnd {
			Set content=InStream.Read(MaxRead)
			Set sc=OutStream.Write($ZCONVERT(content,"O","UTF8"))
			If $$$ISERR(sc) Quit
	} Catch CatchError {
		#dim CatchError as %Exception.SystemException
		Set sc=CatchError.AsStatus()
	Quit sc

If the problem is different, please provide more info/details, maybe a sample XML (not necessarily the original XML).


Thanks for yours answers, I tried your solutions, but it is hard and did not give good results.

To simplify my explanation : I'm reading an XML file from a file-share, and I want to change the XML header encoding from UTF8 to ISO-8859-1, if it happens sometimes.
So the result of my new method should transform the potential header
<?xml version="1.0" encoding="UTF8"?>   

to a new header

<?xml version="1.0" encoding="ISO-8859-1"?>  

Set inputBinaryStream=##class(%Stream.FileBinary).%New()
Set inputBinaryStream.Filename="\\server\your\share\file.xml"
Set outputBinaryStream=##class(%Stream.FileBinary).%New()
Set outputBinaryStream = ##class(Ens.Util.XML.Reader).ChangeXMLStreamEncoding(inputBinaryStream, "ISO-8859-1",outputBinaryStream, .tSC)

; Since the output stream is passed, you can just call (last line) with:
Do ##class(Ens.Util.XML.Reader).ChangeXMLStreamEncoding(inputBinaryStream, "ISO-8859-1",outputBinaryStream, .tSC)


Thank you Enrico for your quick answer. I'm almost there.
To be more precise, we access the fileshare through a EnsLib.FTP.OutboundAdapter, through the method  ..Adapter.GetStream(pRequest.StringValue, .tStream) .

pRequest.StringValue contains the file-share path of the file I want to return.

Here is the full method : 

/// Return the CDA XML file as a %Stream.GlobalBinary
Method GetSoarianXMLCDA(pRequest As Ens.StringRequest, pResponse As %Stream.GlobalBinary) As %Status
// Create the variable tSC (temporary Status Code)
Set tSC = $$$OK

    //Create the stream
    Set tStream=##class(%Stream.GlobalBinary).%New()
    //set the files path to the FTP Adapter
    Set tSC = ..Adapter.GetStream(pRequest.StringValue, .tStream)
    If $$$ISERR(tSC){
       $$$LOGERROR("Error while retrieving Stream from CDA file : tSC = " _ tSC)


 //call here Do ##class(Ens.Util.XML.Reader).ChangeXMLStreamEncoding...
If tStream.SizeGet() > 0{
    Set pResponse = tStream
          $$$LOGERROR("CDA file " _ pRequest.StringValue _" is empty or null")
catch ex {
   Set tSC = ex.AsStatus()

    Quit tSC

The FTP adapter method ..Adapter.GetStream returns a  %GlobalBinaryStream If I read the adapter's code correctly.

Could you please tell me how to use ChangeXMLStreamEncoding() in this methode above ? 

Thanks again


Simply replace the line:
//call here Do ##class(Ens.Util.XML.Reader).ChangeXMLStreamEncoding...

Set outputBinaryStream=##class(%Stream.FileBinary).%New()
Do ##class(Ens.Util.XML.Reader).ChangeXMLStreamEncoding(tStream, "ISO-8859-1",outputBinaryStream, .tSC)
//you may want to check tSC, just in case....
//now on use the header changed outputBinaryStream instead of tStream