Example: Batch Write Operation Using the AWS SDK for .NET Object Persistence Model

using System;
using System.Collections.Generic;
using Amazon.DynamoDBv2;
using Amazon.DynamoDBv2.DataModel;
using Amazon.Runtime;
using Amazon.SecurityToken;

namespace Amazon.DynamoDBv2.Documentation
{
  class ORMTest
  {
    static void Main(string[] args)
    {
      try
      {
        var client = CreateClient();
        DynamoDBContext context = new DynamoDBContext(client);
        SingleTableBatchWrite(context);
        MultiTableBatchWrite(context);
      }
      catch (AmazonServiceException e) { Console.WriteLine(e.Message); }
      catch (Exception e) { Console.WriteLine(e.Message); }

      Console.WriteLine("To continue, press Enter");
      Console.ReadLine();
    }

    private static void SingleTableBatchWrite(DynamoDBContext context)
    {
      Book book1 = new Book
      {
        Id = 902,
        InPublication = true,
        ISBN = "902-11-11-1111",
        PageCount = "100",
        Price = 10,
        ProductCategory = "Book",
        Title = "My book3 in batch write"
      };
      Book book2 = new Book
      {
        Id = 903,
        InPublication = true,
        ISBN = "903-11-11-1111",
        PageCount = "200",
        Price = 10,
        ProductCategory = "Book",
        Title = "My book4 in batch write"
      };

      var bookBatch = context.CreateBatchWrite<Book>();
      bookBatch.AddPutItems(new List<Book> { book1, book2 });

      Console.WriteLine("Performing batch write in SingleTableBatchWrite().");
      bookBatch.Execute();
    }

    private static void MultiTableBatchWrite(DynamoDBContext context)
    {
      // 1. New Forum item.
      Forum newForum = new Forum
      {
        Name = "Test BatchWrite Forum",
        Threads = 0
      };
      var forumBatch = context.CreateBatchWrite<Forum>();
      forumBatch.AddPutItem(newForum);

      // 2. New Thread item.
      Thread newThread = new Thread
      {
        ForumName = "S3 forum",
        Subject = "My sample question",
        KeywordTags = new List<string> { "S3", "Bucket" },
        Message = "Message text"
      };

      DynamoDBOperationConfig config = new DynamoDBOperationConfig();
      config.SkipVersionCheck = true;
      var threadBatch = context.CreateBatchWrite<Thread>(config);
      threadBatch.AddPutItem(newThread);
      threadBatch.AddDeleteKey("some hash attr", "some range attr");

      var superBatch = new MultiTableBatchWrite(forumBatch, threadBatch);
      Console.WriteLine("Performing batch write in MultiTableBatchWrite().");
      superBatch.Execute();
    }

    private static AmazonDynamoDBClient CreateClient()
    {
      var userCredentials = new EnvironmentAWSCredentials();
      var stsClient = new AmazonSecurityTokenServiceClient(userCredentials);
      var sessionCredentials = new RefreshingSessionAWSCredentials(stsClient);
      var config = new AmazonDynamoDBConfig();
      config.ServiceURL = System.Configuration.ConfigurationManager.AppSettings["ServiceURL"];
      var client = new AmazonDynamoDBClient(sessionCredentials, config);
      return client;
    }
  }

  [DynamoDBTable("Reply")]
  public class Reply
  {
    [DynamoDBHashKey]    // Hash key.
    public string Id { get; set; }

    [DynamoDBRangeKey]  // Range key.
    public DateTime ReplyDateTime { get; set; }

    // Properties included implicitly.
    public string Message { get; set; }
    // Explicit property mapping with object persistence model attributes.
    [DynamoDBProperty("LastPostedBy")]
    public string PostedBy { get; set; }
    // Property to store version number for optimistic locking.
    [DynamoDBVersion]
    public int? Version { get; set; }
  }

  [DynamoDBTable("Thread")]
  public class Thread
  {
    // PK mapping.
    [DynamoDBHashKey]
    public string ForumName { get; set; }
    [DynamoDBRangeKey]
    public String Subject { get; set; }
    // Implicit mapping.
    public string Message { get; set; }
    public string LastPostedBy { get; set; }
    public int Views { get; set; }
    public int Replies { get; set; }
    public bool Answered { get; set; }
    public DateTime LastPostedDateTime { get; set; }
    // Explicit mapping (property and table attribute names are different.
    [DynamoDBProperty("Tags")]
    public List<string> KeywordTags { get; set; }
    // Property to store version number for optimistic locking.
    [DynamoDBVersion]
    public int? Version { get; set; }
  }

  [DynamoDBTable("Forum")]
  public class Forum
  {
    [DynamoDBHashKey]
    public string Name { get; set; }
    // All the following properties are explicitly mapped,
    // only to show how to provide mapping.
    [DynamoDBProperty]
    public int Threads { get; set; }
    [DynamoDBProperty]
    public int Views { get; set; }
    [DynamoDBProperty]
    public string LastPostBy { get; set; }
    [DynamoDBProperty]
    public DateTime LastPostDateTime { get; set; }
    [DynamoDBProperty]
    public int Messages { get; set; }
  }

  [DynamoDBTable("ProductCatalog")]
  public class Book
  {
    [DynamoDBHashKey]    // Hash key.
    public int Id { get; set; }
    public string Title { get; set; }
    public string ISBN { get; set; }
    public int Price { get; set; }
    public string PageCount { get; set; }
    public string ProductCategory { get; set; }
    public bool InPublication { get; set; }
  }
}