On Thu, 22 Sep 2016 21:18:35 GMT, Leo wrote:

I'm trying to implement a rest api. It works with a normal request but I'd like to return a jsonp when called with a callback function.

This function returns a json array of all restaurants in the database. 

Json getRestaurants()
    {
        Json restaurantList = Json.emptyObject();
        restaurantList["restaurants"] = Json.emptyArray();
        foreach (doc; collection.find())
        {
            restaurantList["restaurants"] ~= [doc.toJson()];
        }
        return restaurantList;
    }

How could I implement it so that with the url /restaurants?callback=parse it returns parse({"restaurants":[{"_id":"...}]})?

Thank you for taking the time.

If I understand it right, then you can do something like this: 

Json getRestaurants(string callback = "")
{
    if (callback == "parse") {
        return parse({"restaurants": [...]});
    }
    
    Json restaurantList = Json.emptyObject();
    restaurantList["restaurants"] = Json.emptyArray();
    foreach (doc; collection.find())
    {
        restaurantList["restaurants"] ~= [doc.toJson()];
    }
    return restaurantList;
}

BTW, a slightly shorter and more efficient alternative to the foreach loop is restaurantList["restaurants"] = Json(collection.find().map!(d => d.toJson()).array); (the return value of find() is a proper input range).