natural language api in google sheets.gs

function onOpen() {
  var ui = SpreadsheetApp.getUi();

  ui.createMenu("🔮 Predictions for cell")
    .addItem('😃/😡 Sentiment', 'predict_on_row')
    .addToUi();
}

const output_column_number = 2

function predict_on_row() {
  
  var spreadsheet = SpreadsheetApp.getActive();
  
  const row_number = spreadsheet.getActiveCell().getRowIndex()
  const text = spreadsheet.getActiveCell().getValue()
  
  const sentiment_score = CloudNaturalLanguageAPI(text)
  
  spreadsheet.getActiveSheet().getRange(row_number, output_column_number).setValue(sentiment_score)
}


function CloudNaturalLanguageAPI(text) {

  const payload = JSON.stringify(
    {
      "document":{
        "type":"PLAIN_TEXT",
        "language": "EN",
        "content": text
      },
      "encodingType":"UTF8"
    }
  );
  
  const url = 'https://language.googleapis.com/v1/documents:analyzeSentiment?key=' + API_KEY;
  
  const response = UrlFetchApp.fetch(url, {
    method: 'POST',
    contentType: 'application/json',
    payload: payload,
    muteHttpExceptions: true
  }).getContentText();
  
  const json_resp = JSON.parse(response)
  
  Logger.log(json_resp)
  
  return json_resp.documentSentiment.score
}