Middy is not getting a secret from Secret Manager in a NodeJS AWS Lambda

Question

I am using Middy for getting secrets from Secret Manager in a NodeJS AWS Lambda. I did create a role for the Lambda to gain access to the parameter path, but some unknown reason the value is not setting either the context object or the environment variables.

The value of process.env.SSM_PATH is LAMBDA.

This is the code that I am using.

'use strict';

const middy = require('middy');
const { ssm } = require('middy/middlewares');


const handler = async (event, context) => {
    console.log(context);
    console.log(process.env)
    console.log(event);
};

exports.handler = middy(handler).use(ssm({
    setToContext: true,
    paths: {
        'PARAMETER': `/${process.env.SSM_PATH}/PARAMETER`
    }
}));

This is a portion of the policy in IAM for the Lambda.

{
    "permissionsBoundary": {},
    "roleName": "monitor_lambda_role",
    "policies": [
        {
            "document": {
                "Version": "2012-10-17",
                "Statement": [
                    {
                        "Sid": "",
                        "Effect": "Allow",
                        "Action": "sqs:sendMessage",
                        "Resource": "arn:aws:sqs:us-east-1::signed-resources-sqs"
                    },
                    {
                        "Sid": "",
                        "Effect": "Allow",
                        "Action": "ssm:GetParametersByPath",
                        "Resource": "arn:aws:ssm:us-east-1::parameter/LAMBDA/*"
                    },
                    {
                        "Sid": "",
                        "Effect": "Allow",
                        "Action": "kms:Decrypt",
                        "Resource": "arn:aws:ssm:us-east-1::alias/aws/ssm"
                    }
                ]
            },
            "name": "InlinePolicy",

            "arn": "arn:aws:iam:::policy/InlinePolicy"
        }
}

Could be due to the lambda run in an async way, it doesn't wait for the ssm middleware for getting the secrets?

Answer 1

I solve my problem.

There is two options for specifying the secrets that you want to read:

paths (object) (optional*): Map of SSM paths to fetch parameters from, where the key is the prefix for the destination name, and value is the SSM path. Example: {paths: {DB_: '/dev/service/db'}}

names (object) (optional*): Map of parameters to fetch from SSM, where the key is the destination, and value is param name in SSM. Example: {names: {DB_URL: '/dev/service/db_url'}}

In my particular case, I should use the names option.