Docs: remove `logEvent` parameter from Logger constructor setting

[bestickley]

Expected Behaviour

The docs state that Logger's constructor accepts a logEvent parameter to control whether or not logger prints event. But when I try to do this I get an error. See screenshot.

Current Behaviour

Cannot pass logEvent into constructor of Logger.

Code snippet

const logger = new Logger({
  logEvent: true, // ERROR: Object literal may only specify known properties, and 'logEvent' does not exist in 'ConstructorOptions'
});

Steps to Reproduce

1. Reproduce code in code snippet above.
2. See error.

Possible Solution

No response

Powertools for AWS Lambda (TypeScript) version

latest

AWS Lambda function runtime

18.x

Packaging format used

npm

Execution logs

No response

[dreamorosi]

Hi @bestickley, thank you for opening the issue.

The documentation is wrong and we'll use this issue to fix it.

The logEvent property should not be part of the constructor because even with enabled, it can only work when the Logger is used in conjunction with the injectLambdaContext Middy middleware or class method decorator.

This is because we can only log the event when the handler is wrapped by the decorator or middleware. If we allowed the setting in the constructor, this could make customers think that by simply enabling the option Logger will log the event, which is not the case.

We do have an environment variable, but that's mostly to disable the behavior without changing the code either in a dev environment or after deployment.

With this in mind I'm inclined to consider not a bug, not a feature request, but rather an action point to change the docs.

[kaihendry]

I don't quite understand what the process is to log the incoming event.

Idea is to surface it easily, ideally in the AWS console for debugging.

Could that please be documented too?

[am29d]

I agree @kaihendry , we can add a small section specifically for logging events.

[dreamorosi]

Hi @kaihendry - we do have a section dedicated to this feature - which can be found here.

When enabled, the feature instructs the logger instance to emit one log at INFO level containing the payload of the event for that invocation. Given that this is a regular log, you'll be able to see it in the CloudWatch dashboard in all the same places where you already access logs (Log Groups, Tail, Insights, etc.).

Given that the Logger utility must have access to the function event for it to log it, the feature is available only when using the injectLambdaContext Middy middleware or @ injectLambdaContext class method decorator. This is also why - despite the inaccurate documentation - the setting is not available at the constructor level.