Copy YouTube channel video to Drive Spreadsheet (Google Apps Script), spreadsheet template: https://docs.google.com/spreadsheets/d/1LvF0iqeQQyoUc_NjiIYjTvYGtIMWIXFlTHUGhhYXZ5g/edit#gid=0

Code.gs

/**
 * Original Source: https://developers.google.com/youtube/v3/code_samples/apps-script
 * Custom modifications by Matthias Andrasch, CC0 https://creativecommons.org/publicdomain/zero/1.0/deed.de
 * Button solution via: https://www.benlcollins.com/apps-script/google-sheets-button/
 *
 * Get URL, title, thumbnail from playlist or channel (via YouTube Data API)
 * YouTube API data needs to be enabled in "resources" -> "Advanced google services"
 */

function retrieveChannelOrPlaylistVideos() {
  
  // https://stackoverflow.com/questions/45879224/yes-no-user-prompt-to-continue-or-stop-the-script
  var ui = SpreadsheetApp.getUi();
  var response = ui.alert('Soll das Skript "YouTube2Spreadsheet" mit den angegebenen Daten (Zeile 1 und 2) ausgeführt werden?', ui.ButtonSet.YES_NO);
  // Process the user's response.
  if (response == ui.Button.NO) {
   Logger.log('The user clicked "NO" or the close button in the dialog\'s bar');
  } else {
    Logger.log('The user clicked "YES", start script');
  
  var sheet = SpreadsheetApp.getActiveSpreadsheet();
  //var sheet = SpreadsheetApp.getActiveSpreadsheet().getSheetByName(sheetName);
  
  var channelOrPlaylistFromSpreadsheet = sheet.getRange('B1').getValue();
  var idFromSpreadsheet = sheet.getRange('B2').getValue();
  
  if(channelOrPlaylistFromSpreadsheet == "channel"){
    // we get all uploaded videos for a channel with id:
    var results = YouTube.Channels.list('contentDetails', {id: idFromSpreadsheet});
    // Get the playlist ID, which is nested in contentDetails, as described in the
    // Channel resource: https://developers.google.com/youtube/v3/docs/channels
    var playlistId = results.items[0].contentDetails.relatedPlaylists.uploads;
    Logger.log("PlaylistId is, determined via channelId (API): "+playlistId);
  }
  else{
    var playlistId = idFromSpreadsheet;
    Logger.log("PlaylistId set by spreadsheet: "+playlistId);
  }
  
  // get placeholder/default values from row 6
  var defaultCollection = sheet.getRange('C6').getValue();
  var defaultType = sheet.getRange('D6').getValue();
  var defaultLearningResourceType = sheet.getRange('H6').getValue();
  var defaultDiscipline = sheet.getRange('I6').getValue();
  var defaultEducationalContext = sheet.getRange('J6').getValue();
  var defaultLicense =  sheet.getRange('K6').getValue();
  var defaultIntendedEndUserRole = sheet.getRange('L6').getValue();
  var defaultTypicalAgeRangeFrom =  sheet.getRange('M6').getValue();
  var defaultTypicalAgeRangeTo = sheet.getRange('N6').getValue();
  var defaultLanguage = sheet.getRange('O6').getValue();
  var defaultKeyword = sheet.getRange('P6').getValue();
  
    var nextPageToken = '';

    // This loop retrieves a set of playlist items and checks the nextPageToken in the
    // response to determine whether the list contains additional items. It repeats that process
    // until it has retrieved all of the items in the list.
    while (nextPageToken != null) {
      var playlistResponse = YouTube.PlaylistItems.list('snippet', {
        playlistId: playlistId,
        maxResults: 25,
        pageToken: nextPageToken
      });

      for (var j = 0; j < playlistResponse.items.length; j++) {
        var playlistItem = playlistResponse.items[j];
        //Logger.log(playlistItem);
        Logger.log('[%s] Title: %s',
                   playlistItem.snippet.resourceId.videoId,
                   playlistItem.snippet.title);
        
        // https://mashe.hawksey.info/2018/02/google-apps-script-patterns-writing-rows-of-data-to-google-sheets/
        //var ss = SpreadsheetApp.getActiveSpreadsheet();
        
        // The code below logs the index of a sheet named "Expenses"
        
        if (sheet == null) {
          Logger.log("Error: sheet name not found");
        }
        
        sheet.appendRow([
          // title
           playlistItem.snippet.title,
          // uuid
          "",
          // collection
          defaultCollection,
          // type
          defaultType,
          // description
          playlistItem.snippet.description,
          // url
          "https://youtube.com/watch?v="+ playlistItem.snippet.resourceId.videoId,
          // thumbnail
          playlistItem.snippet.thumbnails.high.url,
          // learningResourceType
          defaultLearningResourceType,
          // discipline
          defaultDiscipline,
          // educationalContext
          defaultEducationalContext,
          // license
          defaultLicense,
          // intendedEndUserRole
          defaultIntendedEndUserRole,
          // typicalAgeRangeFrom
          defaultTypicalAgeRangeFrom,
          // typicalAgeRangeTo
          defaultTypicalAgeRangeTo,
          // language
          defaultLanguage,
          // keyword
          defaultKeyword
          ]);

      }
      // use this for dev to only test first items:
      // nextPageToken = null;
      nextPageToken = playlistResponse.nextPageToken;
    } // eo while
    
    } // eo else
}

function clearCrawledData(){
    
  // https://stackoverflow.com/questions/45879224/yes-no-user-prompt-to-continue-or-stop-the-script
  var ui = SpreadsheetApp.getUi();
  var response = ui.alert('Sollen alle eingelesenen Zeilen gelöscht werden?', ui.ButtonSet.YES_NO);
  // Process the user's response.
  if (response == ui.Button.NO) {
   Logger.log('The user clicked "NO" or the close button in the dialog\'s bar');
  } else {
    Logger.log('The user clicked "YES", start script');
    
    var sheet = SpreadsheetApp.getActiveSpreadsheet();
    var range = sheet.getRange("A7:P1000");
    range.clearContent();
    
  } // eo else
}