How to sync data from Coda to Google Sheets and Google Sheets to Coda using Google Apps Script

NVM, got it working with this (might look messy, but at least it works):

    // =======================================
    // Remove deleted rows
    var deleteThisCodaRows = [];
    const regexRowID = /[^\/]*$/;
    allRows['sourceRows'].map(function(row) {
      rowLink = row['cells'].slice(-1)[0]['value'];
      deleteThisCodaRows.push(regexRowID.exec(rowLink)[0].slice(3))
    })
    var body = {
      'rowIds': deleteThisCodaRows,
    };
    CodaAPI.deleteRows(SOURCE_DOC_ID, SOURCE_TABLE_ID, body);
    
    // =======================================