How to programmatically format text between start and end tags and then remove the tags

Edit: the below endeavor is related to Google Apps Script to format text in a Google Doc.

I’m not familiar with JavaScript and really have only done some small bit of R coding and so this effort is a bit of parsing what I can google as well as some trial and error. I’ve had some promising success, but I’m also having some trouble finding a complete answer to the following scenario.

Context

I have a google doc template that has embedded merge codes. A separate application is pulling data fields from objects and related objects and replacing those merge codes with unformatted text. A side effect of this application is that I cannot format the merge codes ahead of time so that when replaced, the text is formatted appropriately. Therefore I’m trying to create a script to run following text merge to programmatically apply some formatting.

What I Need

I have three different styles I need to apply. I am creating code to search for start tags and end tags and then format the text between. In a perfect world the tags would also then be removed from the document leaving only the formatted text behind.

Styled Item	Tags	Formatting to be applied
Requests	<req> </req>	Roboto 10, Bold, #4a5356
Citations	<cit> </cit>	Lato 8, Bold, #4A5356
Conclusions	<con> </con>	Lato 8, Bold, #B38F00

Code so Far

function onOpen() {
  DocumentApp.getUi().createMenu('Butler')
      .addItem('Format Headings', 'FormatRequests')

      .addToUi();
}

function FormatRequests() {
  var startTag = '<req>';
  var endTag = '</req>'
  var body = DocumentApp.getActiveDocument().getBody();
  var para = body.getParagraphs();
  for(var i in para){  
    var from = para[i].findText(startTag);
    var to =  para[i].findText(endTag,from);
    if((to != null && from != null) && ((to.getStartOffset()-1) - (from.getStartOffset()+startTag.length) > 0) ){
      para[i].editAsText().setBold(from.getStartOffset()+startTag.length, to.getStartOffset()-1, true);
    }
  }
}

So far I’ve succeeded in finding the tags and setting text between the tags to bold. But I don’t know how to continue to apply the remainder of the formatting or how to remove the tags once the formatting has been applied.

Any ideas?

Answer

Try this:

function main() {

  handle_tags(['<req>', '</req>'], "Roboto", 10, "Bold", "#4a5356");
  handle_tags(['<cit>', '</cit>'], "Lato", 8, "Bold", "#4a5356");
  handle_tags(['<con>', '</con>'], "Lato", 8, "Bold", "#B38F00");
  
}

function handle_tags(tags, family, size, style, color) {

  var body      = DocumentApp.getActiveDocument().getBody();
  var start_tag = tags[0];
  var end_tag   = tags[1];
  
  var found     = body.findText(start_tag);

  while (found) {
    var elem    = found.getElement();
    var start   = found.getEndOffsetInclusive();
    var end     = body.findText(end_tag, found).getStartOffset()-1;

    elem.setFontFamily(start, end, family);
    elem.setFontSize(start, end, size);
    elem.setForegroundColor(start, end, color);

    switch (style.toLowerCase()) {
      case 'bold': elem.setBold(start, end, true); break;
      case 'italic': elem.setItalic(start, end, true); break;
      case 'underline': elem.setUnderline(start, end, true); break;
    }

    found = body.findText(start_tag, found);
  }

  body.replaceText(start_tag, '');
  body.replaceText(end_tag, '');
}