Sending emails using AWS SDK for .NET Core

In this tutorial, you will learn how to send emails via Yandex Cloud Postbox using the AWS SDK for .Net Core.

To start sending emails:

1. Get your cloud ready.
2. Configure a directory for authentication data.
3. Create and run the application.
4. Check the result.

If you no longer need the resources you created, delete them.

Get your cloud readyGet your cloud ready

Sign up for Yandex Cloud and create a billing account:

1. Navigate to the management console and log in to Yandex Cloud or create a new account.
2. On the Yandex Cloud Billing page, make sure you have a billing account linked and it has the ACTIVE or TRIAL_ACTIVE status. If you do not have a billing account, create one and link a cloud to it.

If you have an active billing account, you can navigate to the cloud page to create or select a folder for your infrastructure.

Learn more about clouds and folders here.

Required paid resourcesRequired paid resources

The infrastructure support costs include:

• Fee for using Yandex Cloud Postbox (see Yandex Cloud Postbox pricing).
• Fee for public DNS queries and DNS zones, if you are creating a resource record in Cloud DNS (see Cloud DNS pricing).

Set up resourcesSet up resources

1. Create a service account.
2. Assign the postbox.sender role to the service account.
3. Create a static access key for the service account. Save the ID and secret key.
4. Create an address.
5. Pass a domain ownership check.

Configure a directory for authentication dataConfigure a directory for authentication data

1. Create a directory to store the authentication data in and navigate to it:

   For macOS and Linux:

   mkdir ~/.aws/
   

   For Windows:

   mkdir C:\Users\<user_name>\.aws\
   

2. In the .aws directory, create a file named credentials, copy the credentials you got when creating a static access key, and paste them into it:

   [default]
   aws_access_key_id = <static_key_ID>
   aws_secret_access_key = <secret_key>
   

3. Create a file named config with the default region settings and copy the following information to it:

   [default]
   region = ru-central1
   endpoint_url = https://postbox.cloud.yandex.net
   

Using environment variablesUsing environment variables

By default, the AWS SDK uses authentication data from environment variables if they are set. These variables have priority over authentication data from the .aws/credentials file.

The following environment variables are supported:

• AWS_ACCESS_KEY_ID: Static key ID.
• AWS_SECRET_ACCESS_KEY: Secret key.

To set environment variables, depending on your operating system, follow these steps:

export AWS_ACCESS_KEY_ID=<static_key_ID>
export AWS_SECRET_ACCESS_KEY=<secret_key>

$Env:AWS_ACCESS_KEY_ID=<static_key_ID>
$Env:AWS_SECRET_ACCESS_KEY=<secret_key>

Create and run the applicationCreate and run the application

1. Get the application code:

   Repository

   Manually

   1. Clone the repository:

      git clone https://github.com/yandex-cloud-examples/yc-postbox-examples
      

   2. Navigate to the folder in the cloned csharp/Postbox/Postbox/ repository.

   3. In the Program.cs file, specify the following:

      • Recipient's email address in the ToAddresses field, e.g., receiver@yourdomain.com. You will need access to this email address for the next step.

      • Sender's email address in the FromEmailAddress field.

        The sender's email domain must match the one specified in the Yandex Cloud Postbox address you created when getting started. For example, if your verified domain is yourdomain.com, you can use addresses like noreply@yourdomain.com or admin@yourdomain.com but not user@mail.yourdomain.com.

   1. Create a directory named postbox-csharp and open it.

   2. Create a file named Program.cs and paste this code into it:

      using Amazon.Runtime;
      using Amazon.SimpleEmailV2;
      using Amazon.SimpleEmailV2.Model;
      
      var client = new AmazonSimpleEmailServiceV2Client(
          new AmazonSimpleEmailServiceV2Config
          {
              ServiceURL = "https://postbox.cloud.yandex.net",
              SignatureMethod = SigningAlgorithm.HmacSHA256,
              SignatureVersion = "4",
              AuthenticationRegion = "ru-central1",
          }
      );
      
      try
      {
          var response = await client.SendEmailAsync(
              new SendEmailRequest
              {
                  Destination = new Destination
                  {
                      ToAddresses = ["<recipient_address>"]
                  },
                  Content = new EmailContent
                  {
                      Simple = new Message
                      {
                          Body = new Body
                          {
                              Text = new Content
                              {
                                  Charset = "UTF-8",
                                  Data = "Hello, world!"
                              }
                          },
                          Subject = new Content
                          {
                              Charset = "UTF-8",
                              Data = "Test email"
                          }
                      }
                  },
                  FromEmailAddress = "<sender_address>"
              });
      
          Console.Write(response.MessageId);
      }
      catch (Exception ex)
      {
          // Logging exceptions in JSON format
          Console.WriteLine(ex);
      }
      

   3. In the Program.cs file, specify the following:

      • Recipient's email address in the ToAddresses field, e.g., receiver@yourdomain.com. You will need access to this email address for the next step.

      • Sender's email address in the FromEmailAddress field.

        The sender's email domain must match the one specified in the Yandex Cloud Postbox address you created when getting started. For example, if your verified domain is yourdomain.com, you can use addresses like noreply@yourdomain.com or admin@yourdomain.com but not user@mail.yourdomain.com.

   4. Create a file named Postbox.csproj and paste this code into it:

      <Project Sdk="Microsoft.NET.Sdk">
      
          <PropertyGroup>
              <OutputType>Exe</OutputType>
              <TargetFramework>net8.0</TargetFramework>
              <ImplicitUsings>enable</ImplicitUsings>
              <Nullable>enable</Nullable>
          </PropertyGroup>
      
          <ItemGroup>
            <PackageReference Include="AWSSDK.SimpleEmailV2" Version="3.7.408.17" />
          </ItemGroup>
      
      </Project>
      

   5. Create a file named Postbox.sln and paste this code into it:

      Microsoft Visual Studio Solution File, Format Version 12.00
      Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Postbox", "Postbox\Postbox.csproj", "{51272D55-8BA2-4072-9445-889E627E605D}"
      EndProject
      Global
        GlobalSection(SolutionConfigurationPlatforms) = preSolution
          Debug|Any CPU = Debug|Any CPU
          Release|Any CPU = Release|Any CPU
        EndGlobalSection
        GlobalSection(ProjectConfigurationPlatforms) = postSolution
          {51272D55-8BA2-4072-9445-889E627E605D}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
          {51272D55-8BA2-4072-9445-889E627E605D}.Debug|Any CPU.Build.0 = Debug|Any CPU
          {51272D55-8BA2-4072-9445-889E627E605D}.Release|Any CPU.ActiveCfg = Release|Any CPU
          {51272D55-8BA2-4072-9445-889E627E605D}.Release|Any CPU.Build.0 = Release|Any CPU
        EndGlobalSection
      EndGlobal
      

2. Run the application:

   dotnet run
   

   Result:

   DB42OLB6KLNJ.7VDE********@ingress2-klg
   

Check the resultCheck the result

Make sure the recipient specified in the file named Program.cs in the ToAddresses field has received an email with the specified parameters.

How to delete the resources you createdHow to delete the resources you created

To stop paying for the resources you created:

1. Delete the address.
2. Delete the DNS zone if you created a resource record in it.