docxtemplater is a Javascript software library that allows to do some templating on the docx and pptx format. https://github.com/open-xml-templating/docxtemplater
docxtemplater can be used to replace placeholders in a word document.
With following document :
Hello {name} !
and following data as JSON :
{ "name" : "John" }
After templating, the document will contain :
Hello John
docxtemplater supports simple replacing, but also loops, conditions and raw xml insertion