GitHub token gen doc (#3463)

* added tempalte example for github token gen + doc

Signed-off-by: Mike Serchenia <michael_serchenia@epam.com>

* added tempalte example for github token gen + doc

Signed-off-by: Mike Serchenia <michael_serchenia@epam.com>

* build doc success, added github with template example

Signed-off-by: Mike Serchenia <michael_serchenia@epam.com>

---------

Signed-off-by: Mike Serchenia <michael_serchenia@epam.com>

docs/api/generator/github.md

@@ -0,0 +1,54 @@
+## GitHub App Authentication Documentation
+
+### 1. Register a GitHub App
+To create a GitHub app, follow the instructions provided by GitHub:
+
+- **Visit**: [Registering a GitHub App](https://docs.github.com/en/apps/creating-github-apps/registering-a-github-app/registering-a-github-app#registering-a-github-app)
+- **Procedure**:
+  - Fill in the necessary details for your app.
+  - Note the `App ID` provided after registration.
+  - At the bottom of the registration page, click on `Generate a private key`. Download and securely store this key.
+
+### 2. Store the Private Key
+After generating your private key, you need to store it securely. If you are using Kubernetes, you can store it as a secret:
+
+```bash
+kubectl create secret generic github-app-pem --from-file=key=path/to/your/private-key.pem
+```
+
+### 3. Set Permissions for the GitHub App
+Configure the necessary permissions for your GitHub app depending on what actions it needs to perform:
+
+- **Visit**: [Choosing Permissions for a GitHub App](https://docs.github.com/en/apps/creating-github-apps/registering-a-github-app/choosing-permissions-for-a-github-app#choosing-permissions-for-rest-api-access)
+- **Example**:
+  - For managing OCI images, set read and write permissions for packages.
+
+### 4. Install Your GitHub App
+Install the GitHub app on your repository or organization to start using it:
+
+- **Visit**: [Installing Your Own GitHub App](https://docs.github.com/en/apps/using-github-apps/installing-your-own-github-app)
+
+### 5. Obtain an Installation ID
+After installation, you need to get the installation ID to authenticate API requests:
+
+- **Visit**: [Generating an Installation Access Token for a GitHub App](https://docs.github.com/en/apps/creating-github-apps/authenticating-with-a-github-app/generating-an-installation-access-token-for-a-github-app#generating-an-installation-access-token)
+- **Procedure**:
+  - Find the installation ID from the URL or API response.
+
+### Example Kubernetes Manifest for GitHub Access Token Generator
+
+```yaml
+{% include 'generator-github.yaml' %}
+```
+
+```yaml
+{% include 'generator-github-example.yaml' %}
+```
+
+```yaml
+{% include 'generator-github-example-basicauth.yaml' %}
+```
+
+### Notes
+- Ensure that all sensitive data such as private keys and IDs are securely handled and stored.
+- Adjust the permissions and configurations according to your specific requirements and security policies.

docs/snippets/generator-github-example-basicauth.yaml

@@ -0,0 +1,26 @@
+{% raw %}
+apiVersion: external-secrets.io/v1beta1
+kind: ExternalSecret
+metadata:
+  name: github-auth-temaplate
+spec:
+  dataFrom:
+  - sourceRef:
+      generatorRef:
+        apiVersion: generators.external-secrets.io/v1alpha1
+        kind: GithubAccessToken
+        name: github-auth-token
+  refreshInterval: "15m"
+  target:
+    template:
+      metadata:
+        annotations:
+          tekton.dev/git-0: "https://github.com"
+      type: kubernetes.io/basic-auth
+      engineVersion: v2
+      data:
+        username: "token"
+        password: "{{ .token }}"
+    name: github-auth-temaplate
+
+{% endraw %}

docs/snippets/generator-github-example.yaml

@@ -1,3 +1,4 @@
+---
 apiVersion: external-secrets.io/v1beta1
 kind: ExternalSecret
 metadata:

hack/api-docs/mkdocs.yml

@@ -62,6 +62,7 @@ nav:
       - Password: api/generator/password.md
       - Fake: api/generator/fake.md
       - Webhook: api/generator/webhook.md
+      - Github: api/generator/github.md
     - Reference Docs:
       - API specification: api/spec.md
       - Controller Options: api/controller-options.md