FastGithub/FastGithub.Dns/GithubRequestResolver.cs
2021-06-15 23:51:11 +08:00

49 lines
1.6 KiB
C#

using DNS.Client.RequestResolver;
using DNS.Protocol;
using DNS.Protocol.ResourceRecords;
using FastGithub.Scanner;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
namespace FastGithub.Dns
{
[Service(ServiceLifetime.Singleton)]
sealed class GithubRequestResolver : IRequestResolver
{
private readonly IGithubScanService githubScanService;
private readonly ILogger<GithubRequestResolver> logger;
public GithubRequestResolver(
IGithubScanService githubScanService,
ILogger<GithubRequestResolver> logger)
{
this.githubScanService = githubScanService;
this.logger = logger;
}
public Task<IResponse> Resolve(IRequest request, CancellationToken cancellationToken = default)
{
var response = Response.FromRequest(request);
var question = request.Questions.FirstOrDefault();
if (question != null && question.Type == RecordType.A)
{
var domain = question.Name.ToString();
var fastAddress = this.githubScanService.FindFastAddress(domain);
if (fastAddress != null)
{
var record = new IPAddressResourceRecord(question.Name, fastAddress);
response.AnswerRecords.Add(record);
this.logger.LogInformation(record.ToString());
}
}
return Task.FromResult<IResponse>(response);
}
}
}