dotcfg is a simple, intuitive way for your app to store configuration data on the filesystem -- ideally within the user's home directory, presumably in a dotfile. If your config data can be represented by a Hash, then dotcfg can easily serialize and persist that data between runs.
dotcfg currently understands JSON and YAML, defaulting to YAML.
3 options:
git clone
gem install
- Bundler
Gemfile
Clone the repo, then cd dotcfg
Optional, if you use direnv and want to use Nix flakes to load a dev env:
direnv allow
From here, use -I lib
with calls to e.g. ruby
or irb
to make dotcfg
available without having the gem installed. e.g.
$ irb -Ilib -rdotcfg
irb(main):001:0> CFG = DotCfg.new 'example.cfg'
=>
#<DotCfg:0x00007f75d06b83a0
...
irb(main):002:0> CFG[:does_not_exist]
=> nil
irb(main):003:0> CFG['hello'] = 'world'
=> "world"
irb(main):004:0> CFG['hello']
=> "world"
irb(main):005:0>
gem install dotcfg
Bundler Gemfile
Add to your Gemfile:
gem 'dotcfg', '~> 1.0'
require 'dotcfg'
# if file exists, read and load it; otherwise initialize the file
CFG = DotCfg.new '~/.example'
CFG[:does_not_exist]
# => nil
CFG['hello'] = 'world'
CFG['hello']
# => "world"
puts CFG.pretty
# ---
# hello: world
CFG.serialize
# => "---\nhello: world\n"
CFG.save
# write to ~/.example
Use JSON
require 'dotcfg'
# if file exists, read and load it; otherwise initialize the file
CFG = DotCfg.new '~/.example', :json
# ...
puts CFG.pretty
# {
# "hello": "world"
# }
CFG.serialize
# => "{\"hello\":\"world\"}"
# ...
When JSON consumes symbols, it emits strings. So if you want to use JSON, use strings rather than symbols for your config items. YAML cycles strings and symbols independently, so stick to one or the other.
PROCS = {
json: {
to: proc { |data| data.to_json },
from: proc { |json| JSON.parse json },
pretty: proc { |data| JSON.pretty_generate data },
},
yaml: {
to: proc { |data| data.to_yaml },
from: proc { |yaml| YAML.load yaml },
pretty: proc { |data| data.to_yaml },
},
}