Today I Learned (til)

A collection of my daily learnings. Some useful, some not so much.

I collect a lot of little snippets and notes that I store in my Obsidian vault for remembering nice tools or helpful actions across my day to day work.

fzf and all its glory

I’ve been using fzf for a while now, and it has completely transformed my command line experience. The ability to fuzzy-find files, commands, and even git branches is a game changer. If you haven’t tried it yet, I highly recommend giving it a go!

In this demo, I’m using fzf to find git project directory and then creating a new tmux window.

ctrl + a + f

ctrl + a is my tmux prefix

tmux config

bind-key -r f display-popup -E "zsh $HOME/.local/scripts/tmux-project.sh"

───────┬──────────────────────────────────────────────────────────────────
       │ File: .local/scripts/tmux-project.sh
───────┼──────────────────────────────────────────────────────────────────
   1   │ #!/usr/bin/env zsh
   2   │
   3   │ selected_dir=$(cd ~/dev; fd -t d -d 2 . --color=always | fzf --an
       │ si --highlight-line -e)
   4   │ if [[ -n "$selected_dir" ]]; then
   5   │     dir_basename=$(basename "$selected_dir")
   6   │     tmux new-window -a -n "${dir_basename:0:6}" -c "$HOME/dev/$se
       │ lected_dir" -k
   7   │ else
   8   │     echo "No directory selected"
   9   │ fi
───────┴──────────────────────────────────────────────────────────────────

ArgoCD multi source applications

I was creating some basic app deployments in ArgoCD and was using a multi source app to pass in values to a Helm chart. Little did I know, that any Kubernetes resource in the path of the ref source will actually also be included in the rendered template.

# yaml-language-server: $schema=https://raw.githubusercontent.com/datreeio/CRDs-catalog/refs/heads/main/argoproj.io/applicationset_v1alpha1.json
apiVersion: argoproj.io/v1alpha1
kind: ApplicationSet
metadata:
  name: external-dns
  namespace: argocd
  labels:
    team: platform
spec:
  ...
  template:
    ...
    spec:
      project: cluster-tools
      sources:
      - repoURL: https://kubernetes-sigs.github.io/external-dns/
        chart: external-dns
        targetRevision: 1.18.0
        helm:
          releaseName: external-dns
          namespace: external-dns
          valueFiles:
          - $values/values.yaml
      - repoURL: https://github.com/foo/bar.git
        targetRevision: HEAD
        path: baz/bar/foo # Any Kubernetes resources in this directory will also be rendered even though ref is defined.
        ref: values

Being able to essentially put any supporting resource in the baz/bar/foo directory makes things easier if the chart does not support the common pattern of extraObjects / extraManifests.

Renovate GitHub Action Migration

Use Renovate packageRules to migrate action references across repos when Github org needs to be changed:

{
  "packageRules": [
    {
      "matchDatasources": ["github-tags"],
      "matchPackageNames": ["old-org/github-workflows"],
      "replacementName": "new-org/github-workflows",
      "groupName": "Github Workflow Migration"
    }
  ]
}

This was super helpful when we migrated our shared workflows over to a new org and needed to update 100s of repos. We then we able to handover the work for merging to the devs responsible for each repo.

Terminal Spotify Client

ncspot is a cross-platform Spotify client for the terminal written in Rust. Lightweight alternative to the bloated Spotify desktop app.

ncspot

Removing Resources from Terraform State

Its the simple stuff I always forget. Remove resource from state but don’t destroy it.

removed {
  from = aws_instance.example

  lifecycle {
    destroy = false
  }
}

The actual resource block (aws_instance.example) must also be removed from your configuration files.