generating an XML file using Ada code

generating an XML file using Ada code

[Stephen Leake]

I'm working on syncing a database between Windows and Android. The Android framework for doing this requires a "changes" file, in either XML or JSON format.

So on the Windows side I need to log all db operations to either xml or json.

Using xmlada, I don't see any way to output a file; I searched for "Text_IO" in the installed library code, and found only input functions. One of the xml tutorials mentions the C function "xmlSaveFormatFile"; I can't find that in the Ada code.

This question has been asked before on this list, several years ago; I hope there is a better answer now.

How can I create an XML file?


For JSON, there is the GNATColl.JSON package, which provides a "Write" function that serializes a JSON object to a string. So I can use that, but I prefer XML (it feels more Ada-like :).

-- Stephe

Re: generating an XML file using Ada code

[Niklas Holsti]

On 16-06-24 17:44 , Stephen Leake wrote:
> I'm working on syncing a database between Windows and Android. The
> Android framework for doing this requires a "changes" file, in either
> XML or JSON format.
>
> So on the Windows side I need to log all db operations to either xml
> or json.
>
> Using xmlada, I don't see any way to output a file; I searched for
> "Text_IO" in the installed library code, and found only input
> functions. One of the xml tutorials mentions the C function
> "xmlSaveFormatFile"; I can't find that in the Ada code.
>
> This question has been asked before on this list, several years ago;
> I hope there is a better answer now.
>
> How can I create an XML file?

I have used XML EZ Out, http://www.mckae.com/xmlEz.html, with good results.

-- 
Niklas Holsti
Tidorum Ltd
niklas holsti tidorum fi
       .      @       .

Re: generating an XML file using Ada code

[Simon Wright]

Stephen Leake <stephen_leake@stephe-leake.org> writes:

> How can I create an XML file?

In ASIS2XML[1] I say

   DOM.Core.Nodes.Print (Doc,
                         Print_Comments => True,
                         Print_XML_PI => True,
                         EOL_Sequence => "");

This produces a single very long line of XML; tidy will make a readable
version.

Looking at DOM.Core.Nodes.Print,

   procedure Print
     (N              : Node;
      Print_Comments : Boolean := False;
      Print_XML_PI   : Boolean := False;
      With_URI       : Boolean := False;
      EOL_Sequence   : String  := Sax.Encodings.Lf_Sequence;
      Encoding       : Unicode.Encodings.Unicode_Encoding :=
        Unicode.Encodings.Get_By_Name ("utf-8");
      Collapse_Empty_Nodes : Boolean := False);
   --  For debugging purposes only!
   --
   --  Same as Write, but the output is done on Stdout.
   --  Warning: the default values for the parameters are not the same as for
   --  write. For the latter, they are chosen so that by default the output is
   --  valid XML, whereas Print is mostly intended to be used for testsuite
   --  purposes, and the default match that goal.

I see I should have used DOM.Core.Nodes.Write! Another example of
scratch development code making it into production.

[1] https://sourceforge.net/p/asis2xml/code/ci/default/tree/asis2xml.adb

Re: generating an XML file using Ada code

[Georg Bauhaus]

On 24.06.16 16:44, Stephen Leake wrote:
> I'm working on syncing a database between Windows and Android. The Android framework for doing this requires a "changes" file, in either XML or JSON format.
>
> So on the Windows side I need to log all db operations to either xml or json.
>
> Using xmlada, I don't see any way to output a file;

Maybe print a DOM like this?
http://docs.adacore.com/xmlada-docs/dom.html#printing-dom-tress

Re: generating an XML file using Ada code

[Vadim Godunko]

On Saturday, June 25, 2016 at 2:41:13 AM UTC+3, Stephen Leake wrote:
> 
> How can I create an XML file?
> 
You can use Matreshka's XML.SAX.Pretty_Writers package to generate XML text file and format it (if necessary). It uses "SAX events" to serialize data, thus you don't need to construct whole XML DOM tree in memory before writing to disk.