.net core 2.1 console app with http client factory question

Hi guys,

I would like to implement a scheduled task which checks an API for every hour and insert data into a database if data is not in the database already. I read some articles and came out with this. I wonder if you can guide me to insert data into a SQL table if it is not already there. (By the way, most probably I will not use the Polly retry mechanism in my code.) I prefer to use raw SQL, it is much simpler for me.

Here is the Program.cs

using System;
using System.IO;
using System.Net.Http;
using System.Threading.Tasks;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using Polly;
using Polly.Extensions.Http;
using Polly.Registry;
namespace TrendyolGamePurchase
{
class Program
{
static async Task Main(string[] args)
{
//Read App Settings
var build = new ConfigurationBuilder();
BuildConfig(build);
var config = build.Build();
Console.Write(config["ConnectionStrings:Development"]);
//Polly Retry
var builder = new HostBuilder()
.ConfigureServices((hostContext, services) =>
{
IPolicyRegistry<string> registry = services.AddPolicyRegistry();
//First Policy
IAsyncPolicy httpWaitAndRetryPolicy =
Policy.HandleResult(r => !r.IsSuccessStatusCode)
.WaitAndRetryAsync(3, retryAttempt => TimeSpan.FromSeconds(Math.Pow(3, retryAttempt)));
registry.Add("SimpleWaitAndRetryPolicy", httpWaitAndRetryPolicy);
//Second Policy
IAsyncPolicy noOpPolicy = Policy.NoOpAsync()
.AsAsyncPolicy();
registry.Add("NoOpPolicy", noOpPolicy);
//Third Policy
var timeOutPolicy = Policy.TimeoutAsync(TimeSpan.FromSeconds(10));
registry.Add("timeOutPolicy", timeOutPolicy);
services.AddHttpClient("TestClient", client =>
{
client.BaseAddress = new Uri("http://test//api/v2/web/game/purchase");
client.DefaultRequestHeaders.Add("Accept", "application/json");
}).AddPolicyHandlerFromRegistry((policyRegistry, httpRequestMessage) =>
{
if (httpRequestMessage.Method == HttpMethod.Post)
{
Console.WriteLine(DateTime.Now);
return policyRegistry.Get>("SimpleWaitAndRetryPolicy");
}
return policyRegistry.Get>("NoOpPolicy");
});
services.AddSingleton();
});
await builder.RunConsoleAsync();
}
static void BuildConfig(IConfigurationBuilder builder)
{
builder.SetBasePath(Directory.GetCurrentDirectory())
.AddJsonFile("appsettings.json", optional: false, reloadOnChange: true);
}
}
}

And here is the BusinessService.cs

using System;
using System.Collections.Generic;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using Microsoft.Extensions.Hosting;
namespace TrendyolGamePurchase
{
public class BusinessService : IHostedService
{
private IHttpClientFactory _httpClientFactory;
public BusinessService(IHttpClientFactory httpClientFactory)
{
_httpClientFactory = httpClientFactory;
}
public async Task StartAsync(CancellationToken cancellationToken)
{
await MakeTestRequestsToRemoteService();
}
public async Task MakeTestRequestsToRemoteService()
{
HttpClient httpClient = _httpClientFactory.CreateClient("TestClient");
var authenticationBytes = Encoding.ASCII.GetBytes("Test:12345");
httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic",
Convert.ToBase64String(authenticationBytes));
httpClient.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
var content = new FormUrlEncodedContent(new[]
{
new KeyValuePair<string, string>("productCode", "1"),
new KeyValuePair<string, string>("quantity","1"),
new KeyValuePair<string, string>("shopNo","Palas"),
new KeyValuePair<string, string>("safeNo","Palas"),
new KeyValuePair<string, string>("cashierNo","Palas")
});
var response = await httpClient.PostAsync("http://test//api/v2/web/game/purchase", content);
}
public Task StopAsync(CancellationToken cancellationToken)
{
return Task.CompletedTask;
}
}
}

1 Reply

Know the answer? Post it — somebody with the same question will find it here.

Mario Scheeren5y ago
OK, first of all:
Be sure to REUSE the HttpClient, bc this will not be disposed right by the GC, and will leak memory.
The SQL will depend on your DataBase ...

INSERT INTO [TableName] (FieldA, FieldB, FieldC)
VALUES ('String', true, 42) ;