
![aws sm](../pictures/diagrams-provider-aws-ssm-parameter-store.png)

## Parameter Store

A `ParameterStore` points to AWS SSM Parameter Store in a certain account within a
defined region. You should define Roles that define fine-grained access to
individual secrets and pass them to ESO using `spec.provider.aws.role`. This
way users of the `SecretStore` can only access the secrets necessary.

``` yaml
{% include 'aws-parameter-store.yaml' %}
```

**NOTE:** In case of a `ClusterSecretStore`, Be sure to provide `namespace` in `accessKeyIDSecretRef` and `secretAccessKeySecretRef`  with the namespaces where the secrets reside.

!!! warning "API Pricing & Throttling"
    The SSM Parameter Store API is charged by throughput and
    is available in different tiers, [see pricing](https://aws.amazon.com/systems-manager/pricing/#Parameter_Store).
    Please estimate your costs before using ESO. Cost depends on the RefreshInterval of your ExternalSecrets.

### IAM Policy

#### Fetching Parameters

The example policy below shows the minimum required permissions for fetching SSM parameters. This policy permits pinning down access to secrets with a path matching `dev-*`. Other operations may require additional permission. For example, finding parameters based on tags will also require `ssm:DescribeParameters` and `tag:GetResources` permission with `"Resource": "*"`. Generally, the specific permission required will be logged as an error if an operation fails.

For further information see [AWS Documentation](https://docs.aws.amazon.com/systems-manager/latest/userguide/sysman-paramstore-access.html).

``` json
{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Action": [
        "ssm:GetParameter*",
      ],
      "Resource": "arn:aws:ssm:us-east-2:1234567889911:parameter/dev-*"
    }
  ]
}
```

#### Pushing Parameters

The example policy below shows the minimum required permissions for pushing SSM parameters. Like with the fetching policy it restricts the path in which it can push secrets too.

``` json
{
    "Action": [
        "ssm:GetParameter*",
        "ssm:PutParameter*",
        "ssm:AddTagsToResource",
        "ssm:ListTagsForResource"
    ],
    "Effect": "Allow",
    "Resource": "arn:aws:ssm:us-east-2:1234567889911:parameter/dev-*"
}
```

### JSON Secret Values

You can store JSON objects in a parameter. You can access nested values or arrays using [gjson syntax](https://github.com/tidwall/gjson/blob/master/SYNTAX.md):

Consider the following JSON object that is stored in the Parameter Store key `friendslist`:

``` json
{
  "name": {"first": "Tom", "last": "Anderson"},
  "friends": [
    {"first": "Dale", "last": "Murphy"},
    {"first": "Roger", "last": "Craig"},
    {"first": "Jane", "last": "Murphy"}
  ]
}
```

This is an example on how you would look up nested keys in the above json object:

``` yaml
apiVersion: external-secrets.io/v1
kind: ExternalSecret
metadata:
  name: extract-data
spec:
  # [omitted for brevity]
  data:
  - secretKey: my_name
    remoteRef:
      key: friendslist
      property: name.first # Tom
  - secretKey: first_friend
    remoteRef:
      key: friendslist
      property: friends.1.first # Roger

  # metadataPolicy to fetch all the tags in JSON format
  - secretKey: tags
    remoteRef:
      metadataPolicy: Fetch
      key: database-credentials

  # metadataPolicy to fetch a specific tag (dev) from the source secret
  - secretKey: developer
    remoteRef:
      metadataPolicy: Fetch
      key: database-credentials
      property: dev
```

### Parameter Versions

ParameterStore creates a new version of a parameter every time it is updated with a new value. The parameter can be referenced via the `version` property

## SetSecret

The SetSecret method for the Parameter Store allows the user to set the value stored within the Kubernetes cluster to the remote AWS Parameter Store.

### Creating a Push Secret

```yaml
{% include "full-pushsecret.yaml" %}
```

#### Additional Metadata for PushSecret

Optionally, it is possible to configure additional options for the parameter. These are as follows:

- type
- keyID
- tier & policies
- encodeAsDecoded

To control this behaviour you can set the following provider's `metadata`:

```yaml
{% include 'aws-pm-push-secret-with-metadata.yaml' %}
```

- `secretType` takes three options. `String`, `StringList`, and `SecureString`, where `String` is the _default_
- `kmsKeyID` takes a KMS Key `$ID` or `$ARN` (in case a key source is created in another account) as a string, where `alias/aws/ssm` is the _default_. This property is only used if `secretType` is set as `SecureString`.
- tier & policies contains advanced policy configs such as `ExpirationNotification`.
- encodeAsDecoded if set to true will get the secrets and push them as plain values when pushing the entire secret (instead of encoding them)
instead of base64 encoding the []byte values from the secret.

#### Check successful secret sync

To be able to check that the secret has been successfully synced you can run the following command:

```bash
kubectl get pushsecret pushsecret-example
```

If the secret has synced successfully it will show the status as "Synced".

#### Test new secret using AWS CLI

To View your parameter on AWS Parameter Store using the AWS CLI, install and login to the AWS CLI using the following guide: [AWS CLI](https://aws.amazon.com/cli/).

Run the following commands to get your synchronized parameter from AWS Parameter Store:

```bash
aws ssm get-parameter --name=my-first-parameter --region=us-east-1
```

You should see something similar to the following output:

```json
{
    "Parameter": {
        "Name": "my-first-parameter",
        "Type": "String",
        "Value": "charmander",
        "Version": 4,
        "LastModifiedDate": "2022-09-15T13:04:31.098000-03:00",
        "ARN": "arn:aws:ssm:us-east-1:1234567890123:parameter/my-first-parameter",
        "DataType": "text"
    }
}
```

## Authentication

See [AWS Authentication](aws-access.md) for all supported methods: controller pod identity, IRSA, static credentials, session tokens, assuming roles, session tags, and remote key prefixes.
