@papandreou This sounds like a very sensible feature - especially as it will reduce servers vulnerability to bad xlsx based inputs.

Regarding implementation, my thoughts are:

• add an options argument to XLSX.readFile() and read() which can contain things like maxRows (or maxCols, etc). It can also indicate appropriate action - e.g. throw, crop, etc.
• The options would be used in all the XLSX.process****Entry functions and passed into the relevant Xform objects
• WorksheetXform would translate an option like "maxRows" into a "maxLength" option to give to the ListXform that handles the "sheetData" tag
• ListXform can perform the appropriate action if the "maxLength" requirement is about to fail

@guyonroche, thanks for the input! I changed the API now so that the limit is configured via an options object passed to XLSX.read(..., {maxRows: 123}) instead. It feels a little awkward to explicitly pass it down like that in so many steps, am I missing something? Is there a more central place where it can be stored?

I don't think there is a completely 'tidy' solution - passing options down through the call stack is ok

@papandreou - I tweaked your changes a bit...

• removed the options from the Workbook document as they weren't used
• moved the check from RowXform (the child) to ListXform (the parent)
• changed the text of the error to 'Max row count exceeded' as it now comes from ListXform
• modified the error handling in base-xform
  Hope that's ok

@guyonroche, thanks a lot for getting back to me so soon and helping me get this into shape! You're an exemplary maintainer.

Hi, trying to get this to work as well. Do you have a code example handy that shows the implementation, I'm struggling to get it to work.

@Clowting this feature adds an argument to the workbook.xlsx.readFile function.
There is an integration test added by Andreas that demonstrates how it works:
https://github.com/guyonroche/exceljs/blob/master/spec/integration/workbook-xlsx-reader.spec.js