google app scripts

slack.gs

var SLACK_WEBHOOK_URL = 'https://hooks.slack.com/services/XXXXXXXXXX';

function onOpen() {
  var spreadsheet = SpreadsheetApp.getActiveSpreadsheet();
  var menuEntries = [
    {
      name: 'Notify to Slack',
      functionName: 'notify',
    },
  ];
  spreadsheet.addMenu('Notify', menuEntries);
}

function notify() {
  var payload = {
    channel: '#target_channel',
    username: 'whoami',
    icon_url: 'https://via.placeholder.com/128',
    text: 'Hello @whoami',
    link_names: 1,
    attachments: [
      {
        title: 'tl;dr',
        text: 'bla bla bla.',
      },
    ],
  };
  var response = requestToSlack_(payload);
}

function requestToSlack_(payload){
  var url = SLACK_WEBHOOK_URL;
  var options = {
    method: 'post',
    contentType : 'application/json',
    payload: JSON.stringify(payload),
  };
  var response = UrlFetchApp.fetch(url, options);
  return response;
}

spreadsheet.gs

var TARGET_SHEET = 'Sheet1';

function onOpen() {
  var spreadsheet = SpreadsheetApp.getActiveSpreadsheet();
  var menuEntries = [
    {
      name: 'Debug cell',
      functionName: 'debug',
    },
  ];
  spreadsheet.addMenu('Debug', menuEntries);
}

function debug() {
  var cell = getCell_(rows, function (rowIndex, columnIndex, cell) {
    return cell === true;
  });
  console.log(cell);
}

function getCell_(rows, predicate) {
  for (var i = 0; i < rows.length; i += 1) {
    var columns = rows[i]
    for (var j = 0; j < columns.length; j += 1) {
      var cell = columns[j];
      if (predicate(i, j, cell)) {
        return {
          rowIndex: i + 1,
          columnIndex: j + 1,
          cell: cell,
        };
      }
    }
  }
  throw new Error('Target cell not found.');
}

function getRows_(sheet, minRows, minColumns, maxRows, maxColumns) {
  var actualMinRows = minRows || 1;
  var actualMinColumns = minColumns || 1;
  var actualMaxRows = maxRows || sheet.getMaxRows();
  var actualMaxColumns = maxColumns || sheet.getMaxColumns();
  var dataRange = sheet.getRange(actualMinRows, actualMinColumns, actualMaxRows, actualMaxColumns);
  return dataRange.getValues();
}

function getSheet_(name) {
  var sheets = SpreadsheetApp.getActive().getSheets();
  for (var i = 0; i < sheets.length; i += 1) {
    if (name === sheets[i].getName()) {
      return sheets[i];
    }
  }
  throw new Error('Target sheet not found.');
}