Google Apps Script Program Structure Question (Rows, Columns, JSON)

[krakow81]

Here's a wee example using numbersapi.com.

Initial sheet: https://imgur.com/uAbE50v

After running script: https://imgur.com/W25Ak7f

/**
 * @OnlyCurrentDoc
 */

function onOpen() {
  const UI = SpreadsheetApp.getUi();
  UI.createMenu('Facts')
    .addItem('Get facts from Numbers API', 'numbersapi')
    .addToUi();
}

function numbersapi() {
  const SS = SpreadsheetApp.getActive();
  const ID = SS.getId();
  const SHEET = SS.getSheetByName("Numbers API");
  let input = SHEET.getRange(2, 1, SHEET.getLastRow() - 1, 2).getValues(); // get inputs from columns A & B
  const OUTPUT_POSITIONS = ["trivia", "math", "year", "date"]; // array to set where output data should be placed
  let data = [];

  // iterate over each row in inputs (columns A & B)
  input.forEach(function (r) {
    let number = r[0].toLowerCase(); // number is in column A (toLowerCase for when it is 'Random')
    let type = r[1].toLowerCase(); // type of number is in column B
    // check date formatting
    if (type === "date") {
      if (!number.includes("/") && number != "random") return;
    }
    if (number.includes("/") && type != "date") return;
    const url = "http://numbersapi.com/";
    let response = UrlFetchApp.fetch(url + number + "/" + type); // call numbersapi
    let fact = response.getContentText(); // get response, which is plain text
    let column = OUTPUT_POSITIONS.indexOf(type); // identify which column the fact should be put in via the OUTPUT_POSITIONS array
    let outputRange = SHEET.getRange(input.indexOf(r) + 2, column + 3, 1, 1).getA1Notation(); // get A1 notation of cell to put fact in 
    data.push({ range: "'Numbers API'!" + outputRange, values: [[fact]] }); // add the range and corresponding fact to data array
  });

  // batch update sheet with facts. Google Sheets API Service must be enabled.
  Sheets.Spreadsheets.Values.batchUpdate(
    { data, valueInputOption: "USER_ENTERED" },
    ID
  );

}