cdk-secret-manager-wrapper-layer

that Lambda layer uses a wrapper script to fetch information from Secrets Manager and create environmental variables.
> idea from source

Updates

2025-03-02: v2.1.0
- Added architecture parameter support for Lambda Layer
- Updated Python runtime from 3.9 to 3.13
- Fixed handler name in example code
- Improved layer initialization and referencing patterns
- Enhanced compatibility with AWS Lambda ARM64 architecture

Example

``ts
import { App, Stack, CfnOutput, Duration } from 'aws-cdk-lib';
import { Effect, PolicyStatement } from 'aws-cdk-lib/aws-iam';
import { Function, Runtime, Code, FunctionUrlAuthType, Architecture } from 'aws-cdk-lib/aws-lambda';
import { CfnSecret } from 'aws-cdk-lib/aws-secretsmanager';
import { SecretManagerWrapperLayer } from 'cdk-secret-manager-wrapper-layer';
const env = {
region: process.env.CDK_DEFAULT_REGION,
account: process.env.CDK_DEFAULT_ACCOUNT,
};
const app = new App();
const stack = new Stack(app, 'testing-stack', { env });

/**
* Example create an Secret for testing.
*/
const secret = new CfnSecret(stack, 'MySecret', {
secretString: JSON.stringify({
KEY1: 'VALUE1',
KEY2: 'VALUE2',
KEY3: 'VALUE3',
}),
});

const lambdaArchitecture = Architecture.X86_64;

const layer = new SecretManagerWrapperLayer(stack, 'SecretManagerWrapperLayer', {
lambdaArchitecture,
});

const lambda = new Function(stack, 'fn', {
runtime: Runtime.PYTHON_3_13,
code: Code.fromInline(
import os
def handler(events, contexts):
env = {}
env['KEY1'] = os.environ.get('KEY1', 'Not Found')
env['KEY2'] = os.environ.get('KEY2', 'Not Found')
env['KEY3'] = os.environ.get('KEY3', 'Not Found')
return env
),
handler: 'index.handler',
layers: [layer.layerVersion],
timeout: Duration.minutes(1),
/**
* you need to define this 4 environment various.
*/
environment: {
AWS_LAMBDA_EXEC_WRAPPER: '/opt/get-secrets-layer',
SECRET_REGION: stack.region,
SECRET_ARN: secret.ref,
API_TIMEOUT: '5000',
},
architecture: lambdaArchitecture,
});

/**
* Add Permission for lambda get secret value from secret manager.
*/
lambda.role!.addToPrincipalPolicy(
new PolicyStatement({
effect: Effect.ALLOW,
actions: ['secretsmanager:GetSecretValue'],
// Also you can use find from context.
resources: [secret.ref],
}),
);

/**
* For Testing.
*/
const FnUrl = lambda.addFunctionUrl({
authType: FunctionUrlAuthType.NONE,
});

new CfnOutput(stack, 'FnUrl', {
value: FnUrl.url,
});
`

Testing


`bash

ex: curl https://sdfghjklertyuioxcvbnmghj.lambda-url.us-east-1.on.aws/

curl ${FnUrl}
{"KEY2":"VALUE2","KEY1":"VALUE1","KEY3":"VALUE3"}
``