Cloudwatch logs on terminal

Question

I am using AWS Lambda for my application. For logs, I have to see in UI only, which I really don't like to see. Is there a way that I could connect to Cloudwatch logs locally and then see the logs by the tail command? Or if I could access Cloudwatch server to see logs? Basically, I wanted to see logs on my terminal. If there is any way to do that, please let me know.

Thanks for your help.

Answer 1

You can use AWS CLI to get your logs in real time. See: get-log-events

AWS doesn't provide a functionality where you can tail the log. There are few 3rd party tools you can use. I have used jorgebastida/awslogs which was sufficient for my needs.

Update 02/25/2021: Thanks to @adavea, I just checked and found AWS has added a new feature to tail the CW logs.

aws.logs.tail

--follow (boolean) Whether to continuously poll for new logs.

Answer 2

There are some command line tools like cwtail and awslogs that do a -f follow tail.

Your other option is a free tool I created called SenseLogs that does a live tail in your browser. It is 100% browser based. See https://github.com/sensedeep/senselogs/blob/master/README.md for details.

Answer 3

On my linux/macosx/cygwin console, this will give you the latest log file.

Substitute $1 with your group name

echo aws logs get-log-events --log-group-name /aws/lambda/$1 --log-stream-name `aws logs describe-log-streams --log-group-name /aws/lambda/$1 --max-items 1 --descending --order-by LastEventTime | grep logStreamName | cut -f2 -d: | sed 's/,//'|sed 's/\"/'\''/g'`| sh -

Note that you will need to install awscli ( https://docs.aws.amazon.com/cli/latest/userguide/cli-chap-install.html )

I wrapped the above in a sh function

function getcw() {
    echo aws logs get-log-events --log-group-name /aws/lambda/$1 --log-stream-name `aws logs describe-log-streams --log-group-name /aws/lambda/$1 --max-items 1 --descending --order-by LastEventTime | grep logStreamName | cut -f2 -d: | sed 's/,//'|sed 's/\"/'\''/g'`| sh -
}

and can view the latest log for my logs in chai-lambda-trigger using the command

$ getcw chai-lambda-trigger

If you wanted just the tail of the output, you could do

$ getcw chai-lambda-trigger | tail