Review Request 111773: Add api for writing ODF that is generated from the ODF RNG file

[Jos van den Oever]

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This is an automatically generated e-mail. To reply, visit:
http://git.reviewboard.kde.org/r/111773/
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(Updated Aug. 3, 2013, 10:41 a.m.)


Review request for Calligra.


Changes
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Fixed issues raised by Thorsten and added more documentation.


Description
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This patch is also available in the branch libs-writeodf-vandenoever-2.

Two years ago I wrote an initial version of this patch and a detailed discussion on the mailing list [1] followed. The main objections to the patch have been dealt with (see below).
Most of this new version was written at Akademy in Bilbao.

Very short summary of the patch:
 This patch should help everybody, young and old, with coding C++ for writing ODF and make errors easier to catch.
 The OpenDocument Format specification is published with a Relax NG file that specifies the XML format. This file can be used to check if ODF files are valid. It can also be used to generate a C++ API headers. This is what this patch does.

Example:
 Instead of writing:
==
  xmlWriter->startElement("text:p");
  xmlWriter->addAttribute("text:style-name", "italic");
  xmlWriter->startElement("text:p");
  xmlWriter->addAttribute("text:style-name", "bold");
  xmlWriter->addTextNode("Hello World!");
  xmlWriter->endElement();
  xmlWriter->endElement();
==
you can write:
==
  text_p p(xmlWriter);
  p.set_text_style_name("italic");
  text_span span(p.add_text_span());
  span.set_text_style_name("italic");
  span.addTextNode("Hello World!");
==

Some advantages:
 - autocompletion when coding: faster coding
 - tag and attribute names are not strings but class and function names: less errors
 - nesting is checked by the compiler
 - you write to elements (span, p), not xmlwriter: easier to read
 - required attributes are part of the element constructor

Implementation considerations: 
 - Calligra is large, so the generated code mixes well with the use of KoXmlWriter and porting can be done in small steps.
 - class and function names are similar to the xml tags with ':' and '-' replaced by '_'.
 - stack based: no heap allocations
 - only header files: all code will inline and have low impact on runtime
 - modular: one header file per namespace to reduce compile overhead
 - code generator is Qt code, part of Calligra and runs as a build step

Not in this patch (and places where you can help in the future):
 - generate enumerations based on Relax NG
 - check data type for attributes (you can still write "hello" to an integer attribute)
 - complete port of Calligra to the generated code
 - improved speed by using static QString instead of const char*

Provided solutions to previously raised issues:
 - modular headers to reduce compile overhead
 - function "end()" to optionally close an element before it goes out of scope
 - use structure of Relax NG file to reduce header sizes by inheritance from common groups
 - provide most KoXmlWriter functionality safely through the element instances
 - closing elements is now automatic at a slight runtime overhead
 

[1] http://lists.kde.org/?t=130768700500002


Diffs (updated)
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  devtools/CMakeLists.txt 15008fb 
  devtools/rng2cpp/CMakeLists.txt PRE-CREATION 
  devtools/rng2cpp/rng2cpp.cpp PRE-CREATION 
  filters/libmso/CMakeLists.txt 6bc145f 
  filters/libmso/shapes.cpp 073e061 
  filters/libmso/shapes2.cpp 0f0b906 
  filters/sheets/excel/import/CMakeLists.txt 2466218 
  filters/sheets/excel/import/excelimporttoods.cc de788d4 
  filters/stage/powerpoint/PptToOdp.h 8d85c1f 
  filters/stage/powerpoint/PptToOdp.cpp 425ac33 
  libs/kotext/KoInlineNote.cpp 6faa9a9 
  libs/odf/CMakeLists.txt 8549ace 
  libs/odf/writeodf/CMakeLists.txt PRE-CREATION 
  libs/odf/writeodf/README.txt PRE-CREATION 
  libs/odf/writeodf/helpers.h PRE-CREATION 
  libs/odf/writeodf/odfwriter.h PRE-CREATION 

Diff: http://git.reviewboard.kde.org/r/111773/diff/


Testing
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Opened several ppt and xls files.
Checked ppt conversion for two files and checked that XML was equivalent.


Thanks,

Jos van den Oever

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