Postman pre-request script for setting token

preRequest.js

const authRequest = {
    url: `${pm.collectionVariables.get("baseUrl")}/auth`,
    method: "POST",
    header: {
      "Version": pm.collectionVariables.get("Version"),
    },
    body: {
      mode: "application/json",
      raw: JSON.stringify({
        username: pm.collectionVariables.get("Username"),
        password: pm.collectionVariables.get("Password"),
      }),
    },
  };
  
  if (
    !pm.collectionVariables.get("Token") ||
    !pm.collectionVariables.get("TokenExpiry")
  ) {
    console.log("Token or expiry date are missing, getting token");
  } else if (pm.collectionVariables.get("TokenExpiry") <= new Date().getTime()) {
    console.log("Token is expired, getting token...");
  } else {
    // Use same token
    return;
  }
  
  pm.sendRequest(authRequest, function (err, res) {
    if (err) {
      console.log(err);
      return;
    }
    var responseJson = res.json();
    console.log("responseJSON", responseJson)
    pm.collectionVariables.set("Token", responseJson.result.token);
    var expiryDate = new Date();
    expiryDate.setHours(expiryDate.getHours() + 4);
    pm.collectionVariables.set("TokenExpiry", expiryDate.getTime());
  });