XLSX to XML with schema map

Question

I have built a couple basic workflows using XML tools on top of XLSX workbooks that are mapped to an XML schema. You would enter data into the spreadsheet, export the XML and I had some scripts that would then work with the data.

Now I'm trying to eliminate that step and build a more integrated and portable tool that others could use easily by moving from XSLT/XQuery to Python. I would still like to use Excel for the data entry, but have the Python script read the XLSX file directly.

I found a bunch of easy to use libraries to read from Excel but they need to explicitly state what cells the data is in, like range('A1:C2') etc. The useful thing about using the XML maps was that users could resize or even move tables to fit different rows and rename sheets. Is their a library that would let me select tables as units?

Another approach I tried was to just uncompress the XLSX and just parse the XML directly. The problem with that is that our data is quite complex (taking up to 30-50 sheets) and parsing that in the uncompressed XLSX structure is really daunting. I did find my XML schema within the uncompressed XLSX, so is there any way to reformat the data into this schema outside of Excel? (basically what Excel does when I save a workbook as an .xml file)

Answer 1

The Excel format is pretty complicated with dependencies between components – you can't for example be sure of that the order of the worksheets in the folder worksheets has any bearing to what the file looks like in Excel.

I don't really understand exactly what you're trying to do but the existing libraries present an interface for client code that hides the XML layer. If you don't want that you'll have to root around for the parts that you find useful. In openpyxl you want to look at the stuff in openpyxl/reader specifically worksheet.py .

However, you might have better luck using lxml as this (using libxml2 in the background) will allow you load a single XML into Python and manipulate it directly using the .objectify() method. We don't do this in openpyxl because XML trees consume a lot of memory (and many people have very large worksheets) but the library for working with Powerpoint shows just how easy this can be.