Status of the Writer import/export filters

LibreOffice Conference 2013 (http://conference.libreoffice.org/2013/en/program/development-1/status-of-the-writer-import-export-filters), Milan
Video record: https://vimeo.com/80676221 (original: http://www.ustream.tv/recorded/39220616, from 0:36:55)

Transcript

1. Status of the Writer import/export filters Miklós Vajna 2013­09­25
2. Introduction
3. 3 / 25 LibreOffice Conference 2013 | Miklós Vajna How to measure an import filter? • Target is to handle every feature that the given format can describe • We want numbers • Number of … handled: • XML tags • Single PRoperty Modifiers • Control words • Shape properties
4. 4 / 25 LibreOffice Conference 2013 | Miklós Vajna How to measure an export filter? • Target is to handle every Writer feature • Checklist, e.g. vmiklos01_rtf_status.ods • UNO filter unhandled properties → • Internal filter unhandled SfxPoolItems → • Word export unimplemented methods →
5. 5 / 25 LibreOffice Conference 2013 | Miklós Vajna Is this optimal? • No, because: • Even if pictures and tables are handled, possibly pictures inside tables need explicit support • Not every item (XML tag, SPRM, etc.) are equally important • Still better than having no numbers at all • Scripts used: swfilters­loconf­milan­2k13.txt
6. Status of the ODT / ODF filter
7. 7 / 25 LibreOffice Conference 2013 | Miklós Vajna ODF import status • ODF is XML­based, so has a schema • Almost everything is imported • As ODF was OOoXML before, with little differences • No domain problems • Writer and ODF concepts are really close to each other • Main task is to keep it up to date
8. 8 / 25 LibreOffice Conference 2013 | Miklós Vajna ODF export status • Simplified architecture: • Iterates over paragraphs, text portions, properties • If something is not exported unhandled property → • Current status is near perfect (apart from occasional bugs) • Keep it up to date • In an ideal case a new property is 3 lines to handle
9. 9 / 25 LibreOffice Conference 2013 | Miklós Vajna LibreOffice­specific extensions • When we add new features, we serialize those from/to ODF, see ODF_Implementer_Notes • Each such commit is turned into an ODF proposal before we hit a release • Still, a slow process • ODF 1.2 is not yet an ISO standard e.g.
10. 10 / 25 LibreOffice Conference 2013 | Miklós Vajna Intentional OOo/LO­specific data • settings.xml's <config:config­item­set> • e.g. ooo:configuration­settings • Contains application­specific configuration – e.g. Writer layout compat settings • Macros: <script:event­listener script:language="ooo:StarBasic" …>
11. 11 / 25 LibreOffice Conference 2013 | Miklós Vajna Summary of ODF filter status • Export is lossless • Modulo the reported bugs in Bugzilla ;­) • What we export is imported lossless as well • Other: reasonably • If only the above would be true for other filters as well
12. Status of DOCX / OOXML filter
13. 13 / 25 LibreOffice Conference 2013 | Miklós Vajna Introduction • OOXML may mean lots of things, here: • OOXML, as in what Word does (there is also an ISO version) • OOXML is DOCX, XLSX, PPTX, drawingml, VML, etc. – here: wordprocessingml • Import is older, from­scratch • Export is newer (only in LO), re­using the DOC export
14. 14 / 25 LibreOffice Conference 2013 | Miklós Vajna OOXML import • Two parts: tokenizer and domain mapper • Problems to be solved by tokenizer: • XML element token → • RTF control word token → • Problems to be solved by the domain mapper: • Section Page style →
15. 15 / 25 LibreOffice Conference 2013 | Miklós Vajna OOXML export • Shared Word export: reused domain mapper • Still not perfect due to domain problems • e.g. textframes: writer and draw textframes ↔ Word old­style frames and rectangle shapes
16. 16 / 25 LibreOffice Conference 2013 | Miklós Vajna OOXML numbers • # of XML elements in OfficeOpenXML­ XMLSchema­Strict.zip / wml.xsd: 546 • # of at least tokenized elements: 461 • # of unhandled elements: 85 • Looks pretty good, but remember: this does not measure the coverage of element attributes, combinations, etc.
17. Status of DOC / WW8 filter
18. 18 / 25 LibreOffice Conference 2013 | Miklós Vajna Introduction • DOC is usually WW8 (Word 97­2003) • Probably the oldest Writer filter • What's possible wrt. Writer Word (up to ↔ 2003) handling is mostly already done • Still, not as up to date as it could be • e.g. commented text ranges are not handled
19. 19 / 25 LibreOffice Conference 2013 | Miklós Vajna Import / export status • Import: • Could measure unhandled FIB entries – rare problem • Can measure SPRM's – more useful • Export: • The export framework is from the WW8 filter • All methods are implemented, not useful to check • Unhandled SfxPoolItems – better to measure this
20. 20 / 25 LibreOffice Conference 2013 | Miklós Vajna WW8 numbers • Specification has character (85), paragraph (93), table (80), section (59) and picture (8) SPRM's 325 in total → • Number of handled SPRMS: 318 • Handling of some may be still problematic, but again – looks pretty good
21. Status of the RTF filter
22. 22 / 25 LibreOffice Conference 2013 | Miklós Vajna What to measure in import • RTF has control words: • A control word can be a flag, a destination, a symbol, a toggle or a value • Shape import is Writer­specific as well (unlike ODF/OOXML/WW8) • Same for math import
23. 23 / 25 LibreOffice Conference 2013 | Miklós Vajna What to measure in export • Uses the shared Word exporter can → check unimplemented methods (almost none) • Control words: as useful as XML tags in the OOXML case • Checklist
24. 24 / 25 LibreOffice Conference 2013 | Miklós Vajna RTF numbers • # of control words from the spec: 1821 • # of LO­specific RTF control words: 4 • obsolete, only there for compatibility reasons • # of handled control words on import: 575 • Does not cover e.g. shape properties • # of handled control words on export: 368 • Math status is on par with OOXML • Easier, due to 1:1 mapping
25. 25 / 25 LibreOffice Conference 2013 | Miklós Vajna Questions? • Anyone? Slides: http://vmiklos.hu/odp