Example SSJS for SFMC that retrieves weather forecast from an external API

getWeather.js

<script runat=server>

var apiKey = 'INSERT_WEATHERSTACK_API_KEY_HERE';
var city = Platform.Request.GetQueryStringParameter('city');

if (city) {

   var url = 'http://api.weatherstack.com/forecast?access_key=' + apiKey + '&query=' + city;

   var weather = Platform.Function.HTTPGet(url);

   var obj = Platform.Function.ParseJSON(weather);

   //Platform.Response.Write(obj.current.temperature);

   Platform.Variable.SetValue('@city', city);
   Platform.Variable.SetValue('@temp', obj.current.temperature);
   Platform.Variable.SetValue('@feels', obj.current.feelslike);

}

</script>

%%[ if not Empty(@city) then ]%%
The current temperature in %%=v(@city)=%% is %%=v(@temp)=%%C and it feels like %%=v(@feels)=%%C.
%%[ endif ]%%