Managing Secrets using Configuration File [page]deterministic

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## Create the Secret {#create-the-config-file}

You can define the `Secret` object in a manifest first, in JSON or YAML format, and then create that object. The [Secret](/docs/reference/generated/kubernetes-api//#secret-v1-core) resource contains two maps: `data` and `stringData`. The `data` field is used to store arbitrary data, encoded using base64. The `stringData` field is provided for convenience, and it allows you to provide the same data as unencoded strings. The keys of `data` and `stringData` must consist of alphanumeric characters, `-`, `_` or `.`.

The following example stores two strings in a Secret using the `data` field.

1. Convert the strings to base64:

```shell echo -n 'admin' | base64 echo -n '1f2d1e2e67df' | base64 ```

> Note: The serialized JSON and YAML values of Secret data are encoded as base64 strings. Newlines are not valid within these strings and must be omitted. When using the `base64` utility on Darwin/macOS, users should avoid using the `-b` option to split long lines. Conversely, Linux users *should* add the option `-w 0` to `base64` commands or the pipeline `base64 | tr -d '\n'` if the `-w` option is not available.

The output is similar to:

``` YWRtaW4= MWYyZDFlMmU2N2Rm ```

1. Create the manifest:

```yaml apiVersion: v1 kind: Secret metadata: name: mysecret type: Opaque data: username: YWRtaW4= password: MWYyZDFlMmU2N2Rm ```

Note that the name of a Secret object must be a valid [DNS subdomain name](/docs/concepts/overview/working-with-objects/names#dns-subdomain-names).

1. Create the Secret using [`kubectl apply`](/docs/reference/generated/kubectl/kubectl-commands#apply):

```shell kubectl apply -f ./secret.yaml ```

The output is similar to:

``` secret/mysecret created ```

To verify that the Secret was created and to decode the Secret data, refer to [Managing Secrets using kubectl](/docs/tasks/configmap-secret/managing-secret-using-kubectl/#verify-the-secret).

### Specify unencoded data when creating a Secret

For certain scenarios, you may wish to use the `stringData` field instead. This field allows you to put a non-base64 encoded string directly into the Secret, and the string will be encoded for you when the Secret is created or updated.

A practical example of this might be where you are deploying an application that uses a Secret to store a configuration file, and you want to populate parts of that configuration file during your deployment process.

For example, if your application uses the following configuration file:

```yaml apiUrl: "https://my.api.com/api/v1" username: "<user>" password: "<password>" ```

You could store this in a Secret using the following definition:

```yaml apiVersion: v1 kind: Secret metadata: name: mysecret type: Opaque stringData: config.yaml: | apiUrl: "https://my.api.com/api/v1" username: <user> password: <password> ```

> Note: The `stringData` field for a Secret does not work well with server-side apply.

When you retrieve the Secret data, the command returns the encoded values, and not the plaintext values you provided in `stringData`.

For example, if you run the following command:

```shell kubectl get secret mysecret -o yaml ```

The output is similar to:

```yaml apiVersion: v1 data: config.yaml: YXBpVXJsOiAiaHR0cHM6Ly9teS5hcGkuY29tL2FwaS92MSIKdXNlcm5hbWU6IHt7dXNlcm5hbWV9fQpwYXNzd29yZDoge3twYXNzd29yZH19 kind: Secret metadata: creationTimestamp: 2018-11-15T20:40:59Z name: mysecret namespace: default resourceVersion: "7225" uid: c280ad2e-e916-11e8-98f2-025000000001 type: Opaque ```

### Specify both `data` and `stringData`

If you specify a field in both `data` and `stringData`, the value from `stringData` is used.

For example, if you define the following Secret:

```yaml apiVersion: v1 kind: Secret metadata: name: mysecret type: Opaque data: username: YWRtaW4= stringData: username: administrat …(trimmed)