を使用した CloudWatch Logs の例 AWS SDK for .NET

    using System;
    using System.Threading.Tasks;
    using Amazon.CloudWatchLogs;
    using Amazon.CloudWatchLogs.Model;

    /// <summary>
    /// Shows how to associate an AWS Key Management Service (AWS KMS) key with
    /// an Amazon CloudWatch Logs log group.
    /// </summary>
    public class AssociateKmsKey
    {
        public static async Task Main()
        {
            // This client object will be associated with the same AWS Region
            // as the default user on this system. If you need to use a
            // different AWS Region, pass it as a parameter to the client
            // constructor.
            var client = new AmazonCloudWatchLogsClient();

            string kmsKeyId = "arn:aws:kms:us-west-2:<account-number>:key/7c9eccc2-38cb-4c4f-9db3-766ee8dd3ad4";
            string groupName = "cloudwatchlogs-example-loggroup";

            var request = new AssociateKmsKeyRequest
            {
                KmsKeyId = kmsKeyId,
                LogGroupName = groupName,
            };

            var response = await client.AssociateKmsKeyAsync(request);

            if (response.HttpStatusCode == System.Net.HttpStatusCode.OK)
            {
                Console.WriteLine($"Successfully associated KMS key ID: {kmsKeyId} with log group: {groupName}.");
            }
            else
            {
                Console.WriteLine("Could not make the association between: {kmsKeyId} and {groupName}.");
            }
        }
    }

    using System;
    using System.Threading.Tasks;
    using Amazon.CloudWatchLogs;
    using Amazon.CloudWatchLogs.Model;

    /// <summary>
    /// Shows how to cancel an Amazon CloudWatch Logs export task.
    /// </summary>
    public class CancelExportTask
    {
        public static async Task Main()
        {
            // This client object will be associated with the same AWS Region
            // as the default user on this system. If you need to use a
            // different AWS Region, pass it as a parameter to the client
            // constructor.
            var client = new AmazonCloudWatchLogsClient();
            string taskId = "exampleTaskId";

            var request = new CancelExportTaskRequest
            {
                TaskId = taskId,
            };

            var response = await client.CancelExportTaskAsync(request);

            if (response.HttpStatusCode == System.Net.HttpStatusCode.OK)
            {
                Console.WriteLine($"{taskId} successfully canceled.");
            }
            else
            {
                Console.WriteLine($"{taskId} could not be canceled.");
            }
        }
    }

    using System;
    using System.Threading.Tasks;
    using Amazon.CloudWatchLogs;
    using Amazon.CloudWatchLogs.Model;

    /// <summary>
    /// Shows how to create an Export Task to export the contents of the Amazon
    /// CloudWatch Logs to the specified Amazon Simple Storage Service (Amazon S3)
    /// bucket.
    /// </summary>
    public class CreateExportTask
    {
        public static async Task Main()
        {
            // This client object will be associated with the same AWS Region
            // as the default user on this system. If you need to use a
            // different AWS Region, pass it as a parameter to the client
            // constructor.
            var client = new AmazonCloudWatchLogsClient();
            string taskName = "export-task-example";
            string logGroupName = "cloudwatchlogs-example-loggroup";
            string destination = "amzn-s3-demo-bucket";
            var fromTime = 1437584472382;
            var toTime = 1437584472833;

            var request = new CreateExportTaskRequest
            {
                From = fromTime,
                To = toTime,
                TaskName = taskName,
                LogGroupName = logGroupName,
                Destination = destination,
            };

            var response = await client.CreateExportTaskAsync(request);

            if (response.HttpStatusCode == System.Net.HttpStatusCode.OK)
            {
                Console.WriteLine($"The task, {taskName} with ID: " +
                                  $"{response.TaskId} has been created successfully.");
            }
        }
    }

    using System;
    using System.Threading.Tasks;
    using Amazon.CloudWatchLogs;
    using Amazon.CloudWatchLogs.Model;

    /// <summary>
    /// Shows how to create an Amazon CloudWatch Logs log group.
    /// </summary>
    public class CreateLogGroup
    {
        public static async Task Main()
        {
            // This client object will be associated with the same AWS Region
            // as the default user on this system. If you need to use a
            // different AWS Region, pass it as a parameter to the client
            // constructor.
            var client = new AmazonCloudWatchLogsClient();

            string logGroupName = "cloudwatchlogs-example-loggroup";

            var request = new CreateLogGroupRequest
            {
                LogGroupName = logGroupName,
            };

            var response = await client.CreateLogGroupAsync(request);

            if (response.HttpStatusCode == System.Net.HttpStatusCode.OK)
            {
                Console.WriteLine($"Successfully create log group with ID: {logGroupName}.");
            }
            else
            {
                Console.WriteLine("Could not create log group.");
            }
        }
    }

    using System;
    using System.Threading.Tasks;
    using Amazon.CloudWatchLogs;
    using Amazon.CloudWatchLogs.Model;

    /// <summary>
    /// Shows how to create an Amazon CloudWatch Logs stream for a CloudWatch
    /// log group.
    /// </summary>
    public class CreateLogStream
    {
        public static async Task Main()
        {
            // This client object will be associated with the same AWS Region
            // as the default user on this system. If you need to use a
            // different AWS Region, pass it as a parameter to the client
            // constructor.
            var client = new AmazonCloudWatchLogsClient();
            string logGroupName = "cloudwatchlogs-example-loggroup";
            string logStreamName = "cloudwatchlogs-example-logstream";

            var request = new CreateLogStreamRequest
            {
                LogGroupName = logGroupName,
                LogStreamName = logStreamName,
            };

            var response = await client.CreateLogStreamAsync(request);

            if (response.HttpStatusCode == System.Net.HttpStatusCode.OK)
            {
                Console.WriteLine($"{logStreamName} successfully created for {logGroupName}.");
            }
            else
            {
                Console.WriteLine("Could not create stream.");
            }
        }
    }

    using System;
    using System.Threading.Tasks;
    using Amazon.CloudWatchLogs;
    using Amazon.CloudWatchLogs.Model;

    /// <summary>
    /// Uses the Amazon CloudWatch Logs Service to delete an existing
    /// CloudWatch Logs log group.
    /// </summary>
    public class DeleteLogGroup
    {
        public static async Task Main()
        {
            var client = new AmazonCloudWatchLogsClient();
            string logGroupName = "cloudwatchlogs-example-loggroup";

            var request = new DeleteLogGroupRequest
            {
                LogGroupName = logGroupName,
            };

            var response = await client.DeleteLogGroupAsync(request);

            if (response.HttpStatusCode == System.Net.HttpStatusCode.OK)
            {
                Console.WriteLine($"Successfully deleted CloudWatch log group, {logGroupName}.");
            }
        }
    }

    using System;
    using System.Threading.Tasks;
    using Amazon.CloudWatchLogs;
    using Amazon.CloudWatchLogs.Model;

    /// <summary>
    /// Shows how to retrieve a list of information about Amazon CloudWatch
    /// Logs export tasks.
    /// </summary>
    public class DescribeExportTasks
    {
        public static async Task Main()
        {
            // This client object will be associated with the same AWS Region
            // as the default user on this system. If you need to use a
            // different AWS Region, pass it as a parameter to the client
            // constructor.
            var client = new AmazonCloudWatchLogsClient();

            var request = new DescribeExportTasksRequest
            {
                Limit = 5,
            };

            var response = new DescribeExportTasksResponse();

            do
            {
                response = await client.DescribeExportTasksAsync(request);
                response.ExportTasks.ForEach(t =>
                {
                    Console.WriteLine($"{t.TaskName} with ID: {t.TaskId} has status: {t.Status}");
                });
            }
            while (response.NextToken is not null);
        }
    }

    using System;
    using System.Threading.Tasks;
    using Amazon.CloudWatchLogs;
    using Amazon.CloudWatchLogs.Model;

    /// <summary>
    /// Retrieves information about existing Amazon CloudWatch Logs log groups
    /// and displays the information on the console.
    /// </summary>
    public class DescribeLogGroups
    {
        public static async Task Main()
        {
            // Creates a CloudWatch Logs client using the default
            // user. If you need to work with resources in another
            // AWS Region than the one defined for the default user,
            // pass the AWS Region as a parameter to the client constructor.
            var client = new AmazonCloudWatchLogsClient();

            bool done = false;
            string newToken = null;

            var request = new DescribeLogGroupsRequest
            {
                Limit = 5,
            };

            DescribeLogGroupsResponse response;

            do
            {
                if (newToken is not null)
                {
                    request.NextToken = newToken;
                }

                response = await client.DescribeLogGroupsAsync(request);

                response.LogGroups.ForEach(lg =>
                {
                    Console.WriteLine($"{lg.LogGroupName} is associated with the key: {lg.KmsKeyId}.");
                    Console.WriteLine($"Created on: {lg.CreationTime.Date.Date}");
                    Console.WriteLine($"Date for this group will be stored for: {lg.RetentionInDays} days.\n");
                });

                if (response.NextToken is null)
                {
                    done = true;
                }
                else
                {
                    newToken = response.NextToken;
                }
            }
            while (!done);
        }
    }

必要なファイルを含めます。

using Amazon;
using Amazon.CloudWatchLogs;
using Amazon.CloudWatchLogs.Model;

Live Tail セッションを開始します。

            var client = new AmazonCloudWatchLogsClient();
            var request = new StartLiveTailRequest
            {
                LogGroupIdentifiers = logGroupIdentifiers,
                LogStreamNames = logStreamNames,
                LogEventFilterPattern = filterPattern,
            };

            var response = await client.StartLiveTailAsync(request);

            // Catch if request fails
            if (response.HttpStatusCode != System.Net.HttpStatusCode.OK)
            {
                Console.WriteLine("Failed to start live tail session");
                return;
            }

Live Tail セッションのイベントは 2 つの方法で処理できます。

            /* Method 1
            * 1). Asynchronously loop through the event stream
            * 2). Set a timer to dispose the stream and stop the Live Tail session at the end.
            */
            var eventStream = response.ResponseStream;
            var task = Task.Run(() => 
            {
                foreach (var item in eventStream)
                {
                    if (item is LiveTailSessionUpdate liveTailSessionUpdate)
                    {
                        foreach (var sessionResult in liveTailSessionUpdate.SessionResults)
                        {
                            Console.WriteLine("Message : {0}", sessionResult.Message);
                        }
                    }
                    if (item is LiveTailSessionStart)
                    {
                        Console.WriteLine("Live Tail session started");
                    }
                    // On-stream exceptions are processed here
                    if (item is CloudWatchLogsEventStreamException)
                    {
                        Console.WriteLine($"ERROR: {item}");
                    }
                }
            });
            // Close the stream to stop the session after a timeout
            if (!task.Wait(TimeSpan.FromSeconds(10))){
                eventStream.Dispose();
                Console.WriteLine("End of line");
            }

            /* Method 2
            * 1). Add event handlers to each event variable
            * 2). Start processing the stream and wait for a timeout using AutoResetEvent
            */
            AutoResetEvent endEvent = new AutoResetEvent(false);
            var eventStream = response.ResponseStream;
            using (eventStream) // automatically disposes the stream to stop the session after execution finishes
            {
                eventStream.SessionStartReceived += (sender, e) =>
                {
                    Console.WriteLine("LiveTail session started");
                };
                eventStream.SessionUpdateReceived += (sender, e) =>
                {   
                    foreach (LiveTailSessionLogEvent logEvent in e.EventStreamEvent.SessionResults){
                        Console.WriteLine("Message: {0}", logEvent.Message);
                    }
                };
                // On-stream exceptions are captured here
                eventStream.ExceptionReceived += (sender, e) => 
                {
                    Console.WriteLine($"ERROR: {e.EventStreamException.Message}");
                };

                eventStream.StartProcessing();
                // Stream events for this amount of time.
                endEvent.WaitOne(TimeSpan.FromSeconds(10));
                Console.WriteLine("End of line");
            }