Are there any code examples on how to send multiple logs to a single CloudWatch log stream using the PutLogEvent API in C#?

CodePudding user response：

Yes, you can use the PutLogEvents method on the AmazonCloudWatchLogsClient class to send multiple logs (commonly referred to as a batch) to a single CloudWatch log stream.

You'll need to construct a PutLogEventsRequest, which has four properties:

• LogGroupName (string)
• LogStreamName (string)
• LogEvents (List<InputLogEvent>, which is essentially a list of Message and Timestamp combinations)
• SequenceToken (string)

The sequence token is a field used to ensure the integrity of a log stream and that log events are written to the log stream in the correct order. All requests require it, other than the first upload to a newly created log stream as per the documentation.

There are 2 ways to get the correct value:

1. You provide it the SequenceToken returned in the response of a previous request

2. You use DescribeLogStreams to list the log events within your log group, filter out your specified log stream based on LogStreamName and then use the value of the UploadSequenceToken in the response, as the SequenceToken for your PutLogEventsRequest

Putting all of that together, this should be a good starting point:

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

var client = new AmazonCloudWatchLogsClient();

var request = new PutLogEventsRequest
{
    LogGroupName = "your-log-group",
    LogStreamName = "your-log-stream",
    SequenceToken = "0000000000000000000000000000000000000000000000000",
    LogEvents = new List<InputLogEvent>
    {
        new InputLogEvent { Message = "Message 1", Timestamp = DateTime.UtcNow },
        new InputLogEvent { Message = "Message 2", Timestamp = DateTime.UtcNow }
    }
};

var response = await client.PutLogEventsAsync(request);
var sequenceTokenFromFirstResponse = response.NextSequenceToken;

var secondRequest = new PutLogEventsRequest
{
    LogGroupName = "your-log-group",
    LogStreamName = "your-log-stream",
    SequenceToken = sequenceTokenFromFirstResponse,
    LogEvents = new List<InputLogEvent>
    {
        new InputLogEvent { Message = "Message 3", Timestamp = DateTime.UtcNow },
        new InputLogEvent { Message = "Message 4", Timestamp = DateTime.UtcNow }
    }
};

var secondResponse = await client.PutLogEventsAsync(secondRequest);