Applying password policies via ElastiCache Parameter Groups

Question

Pulumi · Accepted Answer

To apply password policies using ElastiCache Parameter Groups in AWS, we'll leverage the `aws.elasticache.ParameterGroup` resource from Pulumi's AWS package. This enables us to manage ElastiCache parameter groups, which can contain a configuration for Redis or Memcached.

ElastiCache does not directly deal with password policies like a user authentication system would (which would normally be where you'd apply password policies such as length, complexity, etc.). Instead, ElastiCache parameter groups are used to control the behavior and features of your Redis or Memcached nodes.

For example, if we were using Redis, we might want to set the `requirepass` parameter to enforce that clients connecting to the cache must provide a password. However, please note that the actual enforcement of a password policy (like ensuring complexity requirements) should be handled at the application level, or by some other system responsible for generating and setting these passwords.

Here's how you can use Pulumi to create an ElastiCache Parameter Group with a simple password requirement for Redis:

```typescript
import * as pulumi from '@pulumi/pulumi';
import * as aws from '@pulumi/aws';

// Create a new ElastiCache Parameter Group
const cacheParams = new aws.elasticache.ParameterGroup('cache-parameters', {
    // You must specify the family for the ElastiCache parameter group
    family: 'redis6.x', // Use the correct family for the Redis version
    description: 'A parameter group for Redis with password requirement',
    // The parameters property allows you to set the desired configuration for the cache
    parameters: [{
        name: 'requirepass', // Parameter to set a password for connecting to Redis
        value: 'yourSecurePassword123!', // The actual password should be generated and managed securely
    }],
});

// Export the name of the parameter group
export const parameterGroupName = cacheParams.name;
```

In the code above:

- We import the necessary Pulumi modules for deployment.
- We create a new `ParameterGroup` resource named `cache-parameters`, specifying:
  - The `family` which corresponds to the Redis version we expect to use. This must be one of the supported parameter group families in AWS ElastiCache.
  - A description for the parameter group.
  - The required configuration parameters. Here, we set `requirepass` to enforce a password on the Redis cache. The value provided is an example password; in a real scenario, you'd want to generate and manage this securely, perhaps using a secret management system like AWS Secrets Manager.

Please remember that this does not enforce password complexity or rotation policies; it simply sets a password for accessing the cache.

Don't forget to replace `'yourSecurePassword123!'` with a securely generated password and manage it appropriately. If you're using sensitive data, such as passwords, consider using [Pulumi's secret management](https://www.pulumi.com/docs/intro/concepts/secrets/) to keep them protected.

If you're looking to apply more nuanced password policies (e.g., complexity requirements) in an IAM context, that would involve using something like the `aws.iam.AccountPasswordPolicy` resource. ElastiCache does not handle such policies on a user account level since it's not an identity management service.

To apply the above Pulumi code:

1. Ensure you have the Pulumi CLI and AWS CLI installed and configured with the necessary credentials and default region.
2. Save the above code in a file named `index.ts`.
3. Run `pulumi up` to deploy the changes.

Pulumi will then handle the creation of the parameter group with the settings you've defined.