Servicenow Catalog Client Script to add dynamic options to catalog variable of type choices

script.js

// services categories for the applications that live in the cmdb_ci_services table
var categories = [
  {
    id: 0,
    name: "Access Request",
  },
  {
    id: 1,
    name: "New Database Request",
  },
  {
    id: 2,
    name: "Add New Data Process",
  },
  {
    id: 3,
    name: "Report Request",
  },
  {
    id: 4,
    name: "New Application Request(<40 hrs)",
  },
  {
    id: 5,
    name: "Report Modification",
  },
  {
    id: 6,
    name: "New Project Request",
  },
  {
    id: 7,
    name: "Server Specs Request",
  },
  {
    id: 8,
    name: "Process Modification",
  },
  {
    id: 9,
    name: "New Sites",
  },
  {
    id: 10,
    name: "Modification to Data Process",
  },
  {
    id: 11,
    name: "Server Installs",
  },
  {
    id: 12,
    name: "Application Modification (<40 hrs)",
  },
  {
    id: 13,
    name: "New Org Request",
  },
  {
    id: 14,
    name: "Server Patches",
  },
];

// little helper function to do something like: application_name_like_this_with_lowdash
function createChoicevalue(value) {
  if (typeof value !== "string") {
    return null;
  }
  return value.trim().toLowerCase().replaceAll(" ", "_");
}

// this will return each of the fields that the GlideForm addOption method expects

function createChoice(choice) {
  // choice should be a number always
  if (isNaN(choice)) {
    return null;
  }
  return {
    choiceValue: createChoicevalue(categories[choice].name),
    choiceLabel: categories[choice].name,
  };
}

function setValuesBasedOnTheApplication(newValue) {
  //start of with an empty set of values
  var values = [];

  if (typeof newValue !== "string") {
    return null;
  }

  //Define the values you want to conditionally create options for
  switch (newValue) {
    case "SQL Database":
      values = [
        createChoice(1),
        createChoice(7),
        createChoice(14),
        createChoice(11),
        createChoice(0),
      ];
      break;

    case "ADT Report Emails":
      values = [createChoice(0)];
      break;

    case "HIE Email Alerts Request":
      values = [createChoice(0), createChoice(8)];
      break;
    case "Archer Email Alerts Request":
      values = [createChoice(0), createChoice(8)];
      break;
    case "Share Point":
      values = [createChoice(0), createChoice(9)];
      break;
    case "Nominal Services":
      values = [createChoice(0), createChoice(3), createChoice(12)];
      break;
    case "Data Ingestion-Extraction Process":
      values = [createChoice(2), createChoice(10)];
      break;
    case "Contestations":
      values = [createChoice(0), createChoice(3), createChoice(12)];
      break;
    case "Center Ops Portal":
      values = [createChoice(0), createChoice(3), createChoice(12)];
      break;
    case "CD Reports Portal":
      values = [createChoice(0), createChoice(3)];
      break;
    case "Power Platform":
      values = [createChoice(0), createChoice(4), createChoice(12)];
      break;
    default:
      break;
  }

  return values;
}

function onChange(control, oldValue, newValue, isLoading) {
  if (isLoading || newValue == "") {
    return;
  }

  //   when this value changes we call setValuesBasedOnTheApplication to get the values we will need for the choice options list
  var getApplicationName = g_form.getDisplayValue("application_name");

  //    this will contain an array of objects that looks like this:
  //   [  {choiceValue: '', choiceLabel: ''},  {choiceValue: '', choiceLabel: ''},  {choiceValue: '', choiceLabel: ''}]
  var applicationCategoriesArray =
    setValuesBasedOnTheApplication(getApplicationName);
  //   alert(JSON.stringify(applicationCategoriesArray, null, 2));

  //   making sure we have an array of categories and that is not empty
  if (
    Array.isArray(applicationCategoriesArray) &&
    applicationCategoriesArray.length > 0
  ) {
    createDependentOptions("categories", applicationCategoriesArray, false);
  }
}

//dependentField = name of the field you want to populate with options
//dependentValuesArray = an array of objects
//includeNone set to true or false. true will result in -- None -- being added as a label with no value to position 0
function createDependentOptions(
  dependentField,
  dependentValuesArray,
  includeNone
) {
  var index = 0;
  //Start by clearing the options
  g_form.clearOptions(dependentField);

  //If includeNone is true, add a label for none with a value of ''
  if (includeNone) {
    g_form.addOption(dependentField, "", "-- None --", 0);
    //If none was added, increment the index
    index++;
  }

  for (var i = 0; i < dependentValuesArray.length; i++) {
    g_form.addOption(
      dependentField,
      dependentValuesArray[i].choiceValue,
      dependentValuesArray[i].choiceLabel,
      i + index
    );
  }
}