EnvelopeGenerator/EnvelopeGenerator.Server/EnvelopeGenerator.Server/Services/EnvelopeFinalizationWorker.cs

using EnvelopeGenerator.Application.PdfSigning;
using EnvelopeGenerator.Domain.Constants;
using EnvelopeGenerator.Infrastructure;
using MediatR;
using Microsoft.EntityFrameworkCore;

namespace EnvelopeGenerator.Server.Services;

public sealed class EnvelopeFinalizationWorker(
    IServiceScopeFactory scopeFactory,
    ILogger<EnvelopeFinalizationWorker> logger) : BackgroundService
{
    private static readonly TimeSpan PollInterval = TimeSpan.FromMinutes(1);

    protected override async Task ExecuteAsync(CancellationToken stoppingToken)
    {
        while (!stoppingToken.IsCancellationRequested)
        {
            try
            {
                using var scope = scopeFactory.CreateScope();
                var dbContext = scope.ServiceProvider.GetRequiredService<EGDbContext>();
                var sender = scope.ServiceProvider.GetRequiredService<ISender>();

                var envelopeIds = await dbContext.Envelopes
                    .AsNoTracking()
                    .Where(e => e.Status == EnvelopeStatus.EnvelopeCompletelySigned && e.DocResult == null)
                    .Select(e => e.Id)
                    .ToListAsync(stoppingToken);

                foreach(var envelopeId in envelopeIds)
                {
                    try
                    {
                        await sender.Send(new FinalizeEnvelopeCommand()
                        {
                            Id = envelopeId,
                            BurnedAllowed = false,
                            SaveDocResult = true,
                        }, stoppingToken);
                    }
                    catch(Exception ex)
                    {
                        // TODO: integrate rabbit mq and handle exception (such as delete)
                        logger.LogError(ex, "Unexpected exception happened during finalization of envelope. Envelope ID: {EnvelopeId}", envelopeId);
                    }
                }

                // continue here
                logger.LogDebug("EnvelopeFinalizationWorker found {Count} signed envelope(s) without DOC_RESULT.", envelopeIds.Count);
            }
            catch (OperationCanceledException) when (stoppingToken.IsCancellationRequested)
            {
                break;
            }
            catch (Exception ex)
            {
                logger.LogError(ex, "EnvelopeFinalizationWorker failed while reading envelopes.");
            }

            await Task.Delay(PollInterval, stoppingToken);
        }
    }
}