Using Google Apps Script, how can I download each presentation slide as a pdf?

Question

I'm a bit new to this, so I apologize in advance for any newb related annoyances.

What I'm trying to do is create a google presentation with various images, and then download each slide as a separate pdf. I'm trouble with the downloading as a pdf part. The presentation is being constructed correctly. I've tried a couple different things, but haven't found a working solution yet. The simplest one I tried was:

var newFolder=rootFolder.createFolder(sourceSpreadsheet.getName() + ' - Functionals').setSharing(DriveApp.Access.ANYONE_WITH_LINK, DriveApp.Permission.VIEW);  
var deck = SlidesApp.create(NAME);  // name determined separately
var presentationID = deck.getId();

...

var blob = DriveApp.getFileById(presentationID).getBlob();
newFolder.createFile(blob);

This did create a pdf, but it looks like it was just one blank page. I'm unsure if maybe it needs to run on each slide individually rather than the presentation as a whole. I couldn't find anything to indicate that to be the case though.

The second thing I tried was based on a similar solution I found for a spreadsheet. I don't really understand how changing the URL downloads it as a pdf, and maybe that's related to the issue with it, which is this is resulting in a 404.

var presentation = SlidesApp.openById(presentationID);
var url = presentation.getUrl();
url = url.replace(/edit$/,'');
var url_ext = 'export?exportFormat=pdf&format=pdf' + '&muteHttpExceptions=true' //export as pdf
var response = UrlFetchApp.fetch(url + url_ext, {
                                   headers: {
                                   'Authorization': 'Bearer ' +  token
                                   }
                                   });

Answer 1

I've used the second method to create pdfs of Google Sheets.

The following function could be adapted to create pdfs of your slides. This uses the REST API so that's why you need to construct the URL with parameters according to how you want to format the pdf.

Your formated url will need to look something like this: https://docs.google.com/presentation/d/****presentationId****/export?exportFormat=pdf&format=pdf

You can find other optional parameters for formating the pdf in this function.

function exportPDF(fileId) {
  var ss = SpreadsheetApp.openById(fileId);  
  // Base URL
  var url = "https://docs.google.com/spreadsheets/d/SS_ID/export?".replace("SS_ID", ss.getId());
  /* Specify PDF export parameters
  From: https://code.google.com/p/google-apps-script-issues/issues/detail?id=3579
        https://stackoverflow.com/questions/46088042/margins-parameters-for-spreadsheet-export
  */

  var url_ext = 'exportFormat=pdf&format=pdf'        // export as pdf / csv / xls / xlsx
  + '&size=letter'                       // paper size legal / letter / A4
  + '&portrait=true'                    // orientation, false for landscape
  + '&fitw=true&source=labnol'                          // fit to page width, false for actual size
  + '&top_margin=0.25'              //All four margins must be set!
  +'&bottom_margin=0.25'           //All four margins must be set!
  +'&left_margin=0.25'             //All four margins must be set!
  +'&right_margin=0.25'            //All four margins must be set!
  + '&sheetnames=false&printtitle=false' // hide optional headers and footers
  + '&pagenumbers=false&gridlines=false' // hide page numbers and gridlines
  + '&fzr=true'                         // do not repeat row headers (frozen rows) on each page
  + '&gid=';                             // the sheet's Id

  var token = ScriptApp.getOAuthToken();
  var sheet = ss.getSheets()[0]; //get first sheet

  // Converts to PDF
  var response = UrlFetchApp.fetch(url + url_ext + sheet.getSheetId(), {
      headers: {
        'Authorization': 'Bearer ' +  token
      }
    });

  //convert the response to a blob and store in our array
  var blob = response.getBlob().setName(sheet.getName() + '.pdf');
  var folderId = '**********your folder id here*******************';
  var folder = DriveApp.getFolderById(folderId);
  return folder.createFile(blob).getId();
}

Answer 2

Converting all of the slides in a presentation to individual pdfs

function convertingSlideImagesToPDF() {
  var fldr=DriveApp.getFolderById("FolderID");
  var ss=SlidesApp.openById("PresentationID");
  var slds=ss.getSlides();
  var n=0;
  for(var i=0;i<slds.length;i++) {
    var sldImgA=slds[i].getImages();
    if(sldImgA) { 
      for(var j=0;j<sldImgA.length;j++) {
        var imgName=sldImgA[j].getTitle();
        var base64=Utilities.base64Encode(sldImgA[j].getBlob().getBytes());
        var html='<img src="data:image/jpg;base64,'+base64+'">';
        var blob=null;
        blob=Utilities.newBlob(html, MimeType.HTML).setName('Image' + n++ + ".pdf");
        blob=blob.getAs(MimeType.PDF);
        var file=fldr.createFile(blob);  
      }
    }
  }
}

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