Azure Function Test

#r "Newtonsoft.Json"

using System.Net;
using System.Linq;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Primitives;
using Newtonsoft.Json;

public class AuctionItem
{
    [JsonProperty("itemID")]
    public string itemID { get; set; }

    [JsonProperty("price")]
    public string Price { get; set; }

    [JsonProperty("amount")]
    public string Amount { get; set; }
}

public static IActionResult Run(HttpRequest req, out object outputDocument,
IEnumerable<AuctionItem> inputDocument, ILogger log)
{
    log.LogInformation("C# HTTP trigger function processed a request.");

    string name = req.Query["name"];
    string price = req.Query["price"];
    string amount = req.Query["amount"];

    string command = req.Query["command"];

    outputDocument = null;

    if (!string.IsNullOrEmpty(name) && !string.IsNullOrEmpty(price) && !string.IsNullOrEmpty(amount)) {
        string responseMessage = "{\"Message\":\"Success\",\n\"Data\": [" + "\n";

        if (!string.IsNullOrEmpty(command)) {
            if (command == "1") {
                foreach (var item in inputDocument) {
                    responseMessage += "{\n\t\"itemID\":\"" + item.itemID + "\"," + "\n";
                    responseMessage += "\t\"price\":\"" + item.Price + "\"," + "\n";
                    responseMessage += "\t\"amount\":\"" + item.Amount + "\"}," + "\n";
                }
            } else if (command == "2") {
                var item = inputDocument.Where(x => x.itemID == name).FirstOrDefault();
                if (item != null) {
                    inputDocument = inputDocument.Where(x => x != item);
                }
            } else if (command == "3") {
                responseMessage += "{\n\t\"itemID\":\"" + name + "\",\n";
                responseMessage += "\t\"price\":\"" + price + "\",\n";
                responseMessage += "\t\"amount\":\"" + amount + "\"}\n";


                log.LogInformation(responseMessage);
                outputDocument = new {
                    itemID = name,
                    price = price,
                    amount = amount
                };
            }
        }

        responseMessage += "]}";
        return new OkObjectResult(responseMessage);
    } else {
        outputDocument = null;
        return new BadRequestResult();
    }

}