Dave's Blog

It's been a while since I last posted about the Pi Cluster. So what's on it now?

From memory there is:

• This blog, which is a WriteFreely instance. Super simple blogging platform that uses markdown.
• A matrix, synapse server. Which is essentially a self hosted WhatsApp, quite blown away by how good it is. It's obviously not quite as polished as WhatsApp but it's not far off, all of the core functionality is there, sharing pictures, location, polls and more. I wanted it so I could send automated messages to myself or my partner without having to rely on Telegram (which also makes that relatively easy but supposedly has Russian links – there are further alternatives I'm just a control freak).
• A demo WordPress instance for testing plugins and stuff.
• A single MySQL instance to handle DB storage over the cluster. Not exactly super sophisticated or fault tolerant but fine for my needs.
• Graphana for monitoring stuff, though largely unused yet.
• n8n, this is probably my most used self hosted tool, it's an automation platform with a lovely drag and drop interface. I've set up quite a few things now, for work I have some automations that monitor emails that summarize and report back anything important with the help of AI. Converting emails into Asana tasks and things like that. On a personal level there's a few YouTube channels I watch for stock market tips and they are often long and dull, so I monitor those through their RSS feeds and grab the transcript, summarize it and the send myself a note through the matrix server. I also have another that monitors a Google Sheet with my portfolio in it, alerting me to any major movements.
• For work I'm looking at stream monitoring tech so I rolled my own API with Node/Express and a Rust script and that's being tested there before deployment.
• A few puppeteer based node scripts for monitoring/interacting with sites that don't have API's. I won't mention it here as I'm surely breaking ToS but it summarizes my interactions with people over the course of the day and pops a note in my journal.
• Speaking of journals, that's an instance of SilverBullet which I previously blogged about.

There is definitely more but that's all I can remember for now.

It's getting to the point where it needs a few new nodes. I have a Pi 5 that's not really doing anything so might add that to it. If I had the money I would make another case of 4 x 16GB Pi5's for more demanding tasks (puppeteer for example is quite a heavy load on a Pi 4). 🤔

I've been looking for a self hosted journaling solution for a few weeks now on and off and have tried a few. But today I've settled on SilverBullet. It's incredibly flexible and developer-friendly.

It's also really easy to host in k8s, here's a quick intro into what it can do:

Here's my no frills deployment: (I don't think you really need any frills to be fair)

You probably want to change the PVC storageClassName unless you also use Longhorn.

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: silverbullet-pvc
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 1Gi
  storageClassName: longhorn

---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: silverbullet
spec:
  replicas: 1
  selector:
    matchLabels:
      app: silverbullet
  template:
    metadata:
      labels:
        app: silverbullet
    spec:
      containers:
        - name: silverbullet
          image: ghcr.io/silverbulletmd/silverbullet:v2
          ports:
            - containerPort: 3000
          volumeMounts:
            - mountPath: /space
              name: silverbullet-data
      volumes:
        - name: silverbullet-data
          persistentVolumeClaim:
            claimName: silverbullet-pvc

---
apiVersion: v1
kind: Service
metadata:
  name: silverbullet
spec:
  type: ClusterIP
  selector:
    app: silverbullet
  ports:
    - protocol: TCP
      port: 3000
      targetPort: 3000

All of my services run as ClusterIP as I expose them externally with a Cloudflared Tunnel from inside the cluster. If just using locally then NodePort would suffice.

In the process of moving house (a year ago) my original Raspberry Pi cluster that housed this blog died, or became so overly complicated and cluttered that I decided to start a fresh.

Previously this blog was a WordPress install, which is great, very powerful but overkill for my simple needs. The journey that got me here didn't start out as “let's resurrect my blog”, I was actually looking for a light weight journalling tool.

My as yet unrealised plan was to take all the messages of the day from people relevant to work and personal life be it on email, slack and possibly other platforms and through the power of AI create a journal entry each day – automatically.

Anyway, that has yet to materialise but my journaling requirements were that I wanted an easy to use tool that I could self host, had an API and supported markdown for simple AI-friendly formatting.

There are probably hundreds, definitely tens of options. Eventually I settled on writefreely. It's written in go, is super light weight, has an API, you can self host and it's based around markdown.

Anywho, it's day one of using it. So far so good.

If you want to have a play yourself I crudely documented my setup here:

https://github.com/pintofbeer/writefreely

#cluster #tech #raspberrypi #k8s #k3s