doc: HashiCorp external secret operator

docs/SUMMARY.md

@@ -63,6 +63,7 @@
       * [External Secret Operator (ESO)](user-guide/creating-application/eso/README.md)
         * [AWS Secrets Manager](user-guide/creating-application/eso/aws-eso.md)
         * [Google Secrets Manager](user-guide/creating-application/eso/gcp-eso.md)
+        * [HashiCorp Vault](user-guide/creating-application/eso/hashicorp-eso.md)
 
     * [Environment Overrides](user-guide/creating-application/environment-overrides.md)
     * [Deleting Application](user-guide/deleting-application.md)

docs/user-guide/creating-application/eso/aws-eso.md

@@ -2,7 +2,7 @@
 
 To add secrets from **AWS Secrets Manager**, we need to create a generic Kubernetes secret for AWS authentication.
 
-Create a Kubernetes secret in the namespace in which the application is to be deployed using base64 encoded AWS access-key and secret-access-key. You can use devtron generic chart for this.
+Create a Kubernetes secret in the namespace in which the application is to be deployed using base64 encoded AWS access-key and secret-access-key. You can use Devtron generic chart for this.
 
 **Note:** You don't have to create the Kubernetes secret everytime you create External Secret for the respective namespace.
 

docs/user-guide/creating-application/eso/hashicorp-eso.md

@@ -0,0 +1,59 @@
+# HashiCorp Vault
+
+To incorporate secrets from **HashiCorp Vault**, you need to create a generic Kubernetes secret that will be used for vault authentication. This involves creating a Kubernetes secret in the specific namespace where your application will be deployed. 
+The secret should store the base64-encoded password or token obtained from vault. To simplify the process, you can utilize the Devtron generic chart. An example yaml is given below:
+
+```yaml
+apiVersion: v1
+kind: Secret
+type: Opaque
+data:
+   token: <vault-password>
+metadata:
+   name: vault-token
+   namespace: <namespace>
+```
+
+**Note:** Please note that you don't need to create the Kubernetes secret every time you create an External Secret for the corresponding namespace.
+
+Once you have created the generic secret, follow these steps in the application's Secrets section:
+
+**1. Create a new secret.**
+
+To add a new secret to the application, go to the `App Configuration` section of the application. Then, navigate to the left pane and select the `Secrets` option and click on the `Add Secret` button.
+
+![](https://devtron-public-asset.s3.us-east-2.amazonaws.com/images/creating-application/secrets/hc-add-secret.jpg)
+
+**2. Select `HashiCorp Vault` as the External Secret Operator**
+
+After clicking on the `Add Secret` button, select `HashiCorp Vault` from the dropdown menu for the `Data type` option. Provide a name for the secret you are creating, and then proceed to configure the external secret as described in the next step.
+
+![](https://devtron-public-asset.s3.us-east-2.amazonaws.com/images/creating-application/secrets/hc-secret-type.jpg)
+
+**3. Configure secret:**
+
+To configure the external secret that will be fetched from HashiCorp Vault for your application, you will need to provide specific details using the following key-value pairs:
+
+![](https://devtron-public-asset.s3.us-east-2.amazonaws.com/images/creating-application/secrets/hc-secret-configure.jpg)
+
+
+| Key | Description |
+| :--- | :--- |
+| `vault.server` | Server is the connection address for the Vaultserver, e.g: "https://vault.example.com:8200". |
+| `vault.path` | Specify the path where the secret is stored in Vault. |
+| `tokenSecretRef.name` | Enter the name of the secret that will be used for authentication. |
+| `tokenSecretRef.key` | Specify the key name within the secret that contains the token. |
+| `secretKey` | Provide a name for the secret in Kubernetes. |
+| `key` | Enter the name of the secret in Vault. |
+| `property` | Specify the key within the Vault secret. |
+
+![](https://devtron-public-asset.s3.us-east-2.amazonaws.com/images/creating-application/secrets/tokenSecretRef.jpg)
+
+![](https://devtron-public-asset.s3.us-east-2.amazonaws.com/images/creating-application/secrets/hc-eso.jpg)
+
+**4. Save secret.**
+
+After configuring the external secret from HashiCorp Vault, proceed to save the secret by clicking on the `Save` button. 
+
+By following the steps mentioned above and configuring these values correctly, you can seamlessly fetch and utilize external secrets from HashiCorp Vault within your application environment by deploying the application.
+