How to get the latest version of a lambda layer?

[timandy]

I have a lambda layer with name, but the version may be published at some time.
How to get the latest version of the layer?
Does the code work?

const latestLayer = lambda.LayerVersion.fromLayerVersionArn(this, 'mediaxFFmpegLayer', `arn:aws:lambda:${Aws.REGION}:${Aws.ACCOUNT_ID}:layer:layer-name`)`

[peterwoodworth]

Answer: CDK won't look anything up in your AWS account regarding your Lambda Layer - so if you need a specific version of that layer, you will have to include that version in the arn that you pass in when importing.
If you need to programatically fetch the version of your arn, follow the following advice from our best practices page, see Commit cdk.context.json on this page for more information

If you need some value (from AWS or elsewhere) for which there is no native CDK context provider, we recommend writing a separate script. The script should retrieve the value and write it to a file, then read that file in your CDK app. Run the script only when you want to refresh the stored value, not as part of your regular build process.

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[dil-anovosz]

Is the link broken?

[jjrdevspace01]

@peterwoodworth what about if you dont need a specific version, just the latest version, i have tried $LATEST or even omitting the version and nothing seems to work, its quite fiddly at the moment has i dont have console access directly and if i deploy my stack with an unavailable version number it breaks the cloudformation stack. It feel like it should be possible to request the latest as i have noticed its a feature of Amplify to request the latest version of a layer so surely a similar feature exists in CDK?

[gavihs]

I had a similar situation and this is how I solved this
I have the following pattern
-> Main Stack
|----> LambdaLayerNestedStack: In this I create an list of the lambda layers created along with their ARN's and send it back to the main stack
|----> LambdaFunctionNestedStack: I pass the list of Lambda layers to this nested stack and here I have the latest version of the lambda layer

Hope this helps; if you need more clarity reach out to me

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