Innovenergy_trunk/csharp/Lib/Victron/VictronVRM/FlurlExtensions.cs

using System.Net;
using System.Text.Json.Nodes;
using Flurl.Http;
using Flurl.Http.Content;
using static System.Net.Http.HttpMethod;

namespace InnovEnergy.Lib.Victron.VictronVRM;

public static class FlurlExtensions
{

    public static async Task<JsonNode> TryGetJson(this IFlurlRequest request)
    {
        var stream = await TryRequest(request, Get).ReceiveStream();
        return JsonNode.Parse(stream)!;
    }

    public static async Task<JsonNode> TryPostJson(this IFlurlRequest request, JsonObject? content = null)
    {
        var stream = await TryRequest(request, Post, content).ReceiveStream();
        return JsonNode.Parse(stream)!;
    }

    private static async Task<IFlurlResponse> TryRequest(this IFlurlRequest request, HttpMethod verb, JsonObject? data = null)
    {
        var jsonContent = data is null
                        ? null 
                        : new CapturedJsonContent(data.ToJsonString());

        var delayMs = 50;
        
        while (true)
        {
            try
            {
                return await request.SendAsync(verb, jsonContent);
            }
            catch (FlurlHttpException e) when (e.StatusCode == (Int32)HttpStatusCode.TooManyRequests)
            {
                if (delayMs > 2000)
                    throw;
                
                await Task.Delay(delayMs);
                delayMs = delayMs * 2 + Random.Shared.Next() % 4; 
            }
        }
        
    }
}