API/function to read number of words in .doc, .xlsx, .pptx and PDF files

[MichalPL]

Hi, have you heard of any APIs or modules/libraries/functions that would allow me to easily count the total number of words in a bunch of Microsoft Office files uploaded to the server? Word, Excel and PowerPoint.
Plus PDFs, if possible.

[gizmola]

No, and I doubt you will find any.   

In the past there were few different paths: 

• try and use apps like openoffice to open ms documents and use the openoffice api
• Use windows specific integrations

In recent years, microsoft has introduced "add-ins" primarily for companies looking to integrate their office data into intranets or publish data on a website:  https://learn.microsoft.com/en-us/office/dev/add-ins/overview/office-add-ins

These are avenues I'd look into.  I don't know what scale you are looking at.  I worked for a company some years ago with millions of customer accounts, and that product needed to transform any of a large number of different document formats, into other formats, and this involved a complicated ingestion process that, depending on the type of document, passed it on to a cluster of different servers that would run native apps and perform various processes often running macros and other code native to the specific application, before exporting to other formats.  I suspect you would need something similar.  

And of course pdf is a whole different company and different platform.