MailKitSimplified.Sender 0.1.2.3

MailKitSimplified.Sender

Sending and receiving emails sounds simple, after all, electronic mail existed decades before the Internet. If you're looking for a an all-in-one .NET solution for email, you'll quickly discover MailKit is recommended by even the likes of Microsoft. Unfortunately for new users though, MailKit can do too much, so when I first started using it I was surprised at how many configuration steps were involved in getting it set up, and on the receiving end how poorly some real-world SMTP servers out there implement the standard. The aim of this package is to make sending an email as simple as possible.

Usage

Setup

If you're not sure what dependency injection is then just use this:

using var smtpSender = MimeMessageSender.Create("smtp.example.com");

Sending Mail

var email = smtpSender.WriteEmail
    .From("me@example.com", "My Name")
    .To("you@example.com", "Your Name")
    .To("friend1@example.com")
    .To("friend2@example.com")
    .Subject("Hey You")
    .Body("Hello World")
    .Attach("C:/Temp/attachment1.txt", "C:/Temp/attachment2.pdf")
    .Attach("./attachment3.docx");

await email.SendAsync();

An email must have a From and at least one To address, order does not matter. Setting a subject or body will overwrite previous ones to make things simpler. Any issues will throw an exception, but you can also opt to just log them and continue with a false output:

bool isSent = await smtpSender.WriteEmail
    .From("me@example.com")
    .To("you@example.com")
    .TrySendAsync();

_logger.LogInformation("Email {result}.", isSent ? "sent" : "failed to send");

Further examples (detailed MailKit SMPT server logs etc.) can be found in MailKitSimplifiedSenderUnitTests and the example solution file.

Dependency Injection

This is recommended over manual setup as the built-in garbage collector will handle lifetime and disposal.

public class Program
{
    public static async Task Main(string[] args)
    {
        IHost host = Host.CreateDefaultBuilder(args)
            .ConfigureServices((context, services) =>
            {
                services.AddHostedService<Worker>();
                ConfigureServices(services, context.Configuration);
            })
            .Build();

        await host.RunAsync();
    }

    public static void ConfigureServices(IServiceCollection services, IConfiguration configuration)
    {
        // This adds IOptions<EmailSenderOptions> from appsettings.json
        services.Configure<EmailSenderOptions>(configuration
            .GetRequiredSection(EmailSenderOptions.SectionName));
        services.AddTransient<IFileHandler, FileHandler>();
        services.AddTransient<IMimeAttachmentHandler, MimeAttachmentHandler>();
        services.AddTransient<IEmail, Email>();
        services.AddTransient<IEmailWriter, EmailWriter>();
        services.AddTransient<IEmailSender, MimeMessageSender>();
    }
}

This can then be referenced with no other setup in your service as follows:

public class EmailService {

    private readonly IEmailSender _smtpSender;

    public EmailService(IEmailSender smtpSender) {
        _smtpSender = smtpSender;
    }
}

Receiving Mail

Coming in a sister package in the near future.