cdk logs

[Elad Ben-Israel]

PR	Champion
#

Description

$ cdk deploy
...
$ cdk logs
[construct path] [timestamp] text
[consrruct path] [timestamp] text

This command will query all the log groups in the CDK all from CloudWatch Logs and will print all the log events starting from deployment end time until now.

$ cdk logs --follow|-f

Will continue to stream incoming logs from CloudWatch every few seconds.

We will need to add framework support for registering log groups by L2 resources:

class lambda.Function {
  constructor() {
    // ...
    Stack.of(this).addLogs(Logs.fromCloudWatch(`lambda/{this.functionName}`);
  }
}

Since the log group name is likely to include deploy-bound values (such as the AWS Lambda function name), the addLogs() method will simply add a CfnOutput to the stack which will include comma-separated names of all the log groups in this app. The output will have a well known name which the CLI will use to query the log groups associated with this app.

Progress

• Tracking Issue Created
• RFC PR Created
• Core Team Member Assigned
• Initial Approval / Final Comment Period
• Ready For Implementation
  • implementation issue 1
• Resolved

[Henry]

I've implemented a similar mechanism in CDK-Watch which derives the function names by looking up the resource in CF using its logical ID. You should be able to run cdkw logs "Path/To/API/**" to match all lambdas under this path and poll their log streams.

I'm also experimenting with adding a Lambda Extension that forwards logs onto an APIGW WebSocket API, allowing for real-time lambda logs in the CLI.