docs: example deployment for kubernetes (#754)

* Adding docs on how to install with Kubernetes manifests.

* docs: community section

---------

Co-authored-by: Felipe Martin <812088+fmartingr@users.noreply.github.com>
Co-authored-by: Felipe M <me@fmartingr.com>

docs/Installation.md

@@ -2,13 +2,18 @@ There are several installation methods available :
 
 <!-- TOC -->
 
-- [Using Precompiled Binary](#using-precompiled-binary)
-- [Building From Source](#building-from-source)
-- [Using Docker Image](#using-docker-image)
+- [Supported](#supported)
+  - [Using Precompiled Binary](#using-precompiled-binary)
+  - [Building From Source](#building-from-source)
+  - [Using Docker Image](#using-docker-image)
+- [Community provided](#community-provided)
+  - [Using Kubernetes manifests](#using-kubernetes-manifests)
 
 <!-- /TOC -->
 
-## Using Precompiled Binary
+## Supported
+
+### Using Precompiled Binary
 
 Download the latest version of `shiori` from [the release page](https://github.com/go-shiori/shiori/releases/latest), then put it in your `PATH`.
 
@@ -28,15 +33,15 @@ source $HOME/.profile
 
 On Windows, you can simply set the `PATH` by using the advanced system settings.
 
-## Building From Source
+### Building From Source
 
 Shiori uses Go module so make sure you have version of `go >= 1.14.1` installed, then run:
 
 ```
 go get -u -v github.com/go-shiori/shiori
 ```
 
-## Using Docker Image
+### Using Docker Image
 
 To use Docker image, you can pull the latest automated build from Docker Hub :
 
@@ -49,3 +54,110 @@ If you want to build the Docker image on your own, Shiori already has its [Docke
 ```
 docker build -t shiori .
 ```
+
+## Community provided
+
+Below this there are other ways to deploy Shiori which are not supported by the team but were provided by the community to help others have a starting point.
+
+### Using Kubernetes manifests
+
+If you're self-hosting with a Kubernetes cluster, here are manifest files that
+you can use to deploy Shiori:
+
+`deploy.yaml`:
+
+```yaml
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: shiori
+  labels:
+    app: shiori
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: shiori
+  template:
+    metadata:
+      labels:
+        app: shiori
+    spec:
+      volumes:
+      - name: app
+        hostPath:
+          path: /path/to/data/dir
+      containers:
+      - name: shiori
+        image: ghcr.io/go-shiori/shiori:latest
+        command: ["/usr/bin/shiori", "serve", "--webroot", "/shiori"]
+        imagePullPolicy: Always
+        ports:
+        - containerPort: 8080
+        volumeMounts:
+        - mountPath: /srv/shiori
+          name: app
+        env:
+        - name: SHIORI_DIR
+          value: /srv/shiori
+        - name: HTTP_ROOT_PATH
+          value: "/shiori"
+```
+
+Here we are using a local directory to persist Shiori's data. You will need
+to replace `/path/to/data/dir` with the path to the directory where you want
+to keep your data. Since we haven't configured a database in particular,
+Shiori will use SQLite. I don't think Postgres or MySQL is worth it for
+such an app, but that's up to you. If you decide to use SQLite, I strongly
+suggest to keep `replicas` set to 1 since SQLite usually allows at most
+one writer to proceed concurrently.
+
+Also, not that we're serving the app on the `/shiori` suffix. This is
+only necessary if you want to access Shiori with an URL that looks like:
+`http://your_domain_name/shiori`. This is also why we override the container's
+command: to pass the webroot. If you want to use such suffix, you'll probably
+need to deploy an ingress as well:
+
+`ingress.yaml`:
+
+```yaml
+apiVersion: networking.k8s.io/v1
+kind: Ingress
+metadata:
+  name: shiori
+spec:
+  ingressClassName: nginx
+  rules:
+  - http:
+      paths:
+      - path: /shiori
+        pathType: Prefix
+        backend:
+          service:
+            name: shiori
+            port:
+              number: 8080
+```
+
+Finally, here is the service's config:
+
+`service.yaml`
+
+```yaml
+apiVersion: v1
+kind: Service
+metadata:
+  name: shiori
+spec:
+  type: NodePort
+  selector:
+    app: shiori
+  ports:
+  - protocol: TCP
+    port: 8080
+    targetPort: 8080
+    nodePort: 32654
+```
+
+I'm using the NodePort type for the service so I can access it easily on
+my local network, but it's not necessary if you setup the ingress.