As I indicated on Twitter earlier tonight, I’m working with the new Policyfile feature of ChefDK. While converting my personal systems’ repository to use Policyfile instead of roles, I found myself writing this Policyfile:

name 'home_server'
default_source :community

cookbook 'build-essential'
cookbook 'packages', git: '', branch: 'multipackage'
cookbook 'users', path: '../housepub-chef-repo/cookbooks/users'
cookbook 'sudo'
cookbook 'runit'
cookbook 'ntp'
cookbook 'openssh'
cookbook 'postfix'

No big deal, but I found the repetition… redundant. Several of these cookbooks are fine floating on the latest version from Supermarket - everything but packages and users. So I thought, “wouldn’t it be great if entries in the run list were automatically added as dependencies?”

Then, I added chef-client-runit to the run list, but I didn’t add it as a cookbook entry, performed the chef update, and reran my chef provision command, and wound up with chef-client-runit being converged.

To illustrate this with a really simple example, I confirmed with zsh:

% cd ~/Development/sandbox/test
% chef generate policyfile

Then edit the Policyfile.rb:

name "example_application"
default_source :community
run_list "zsh"

Note that there is no cookbook line here.

% chef install
Building policy example_application
Expanded run list: recipe[zsh]
Caching Cookbooks...
Using      zsh 1.0.1

Lockfile written to /Users/jtimberman/Development/sandbox/test/Policyfile.lock.json

And if we examine the Policyfile.lock.json, we see:

  "revision_id": "e8b5b48d35f4a8efcd037ef6c9cc8e34f901561ffef160bd0a57ca1b612a1179",
  "name": "example_application",
  "run_list": [
  "cookbook_locks": {
    "zsh": {
      "version": "1.0.1",
      "identifier": "b512ef33af29b8d34ad7e4e9b6ad38d42dea4945",
      "dotted_decimal_identifier": "50967789358229944.59473511204894381.62483954551109",
      "cache_key": "",
      "origin": "",
      "source_options": {
        "artifactserver": "",
        "version": "1.0.1"
  } <SNIP>

Yay! Shoutout to Dan DeLeo for preemptively implementing features I didn’t even know I wanted yet :-).