function doGet() {

  //get the data from the spreadsheet into a multidimensional array
  var data = SpreadsheetApp.getActiveSheet().getDataRange().getValues();

  //take the first row of header information and save it into its own array
  var header = data.shift();

  //create an empty array to store our objects after we build them
  var apiData = [];

  data.forEach(function(row) {
    //create an empty object
    var eachObj = {};

    for(var i = 0; i < header.length; i++) {
      //match the keys and values
      eachObj[header[i]] = row[i];
    }
    //add this object to the array
    apiData.push(eachObj);

  });

  //return the array of objects as JSON
  return ContentService.createTextOutput(JSON.stringify(apiData)).setMimeType(ContentService.MimeType.JSON);
}