Merge pull request #403 from DannyBen/add/erb-config

Pre-process config files using ERB

Author: DannyBen

lib/bashly/config.rb

@@ -2,15 +2,19 @@
 
 module Bashly
   # A convenience class to use either a hash or a filename as a configuration
-  # source
+  # source.
+  #
+  # When a filename is provided, it is loaded with these extra features:
+  # - Support for `import` keyword to merge additional YAML files
+  # - Preprocessing with ERB
   class Config
     using ComposeRefinements
 
     attr_reader :config
 
     def self.new(config)
       if config.is_a? String
-        YAML.load_file(config).compose
+        YAML.load_erb_file(config).compose
       else
         config
       end

lib/bashly/extensions/yaml.rb

@@ -4,5 +4,9 @@ module YAML
   # StackOverflow: https://stackoverflow.com/questions/71191685/visit-psych-nodes-alias-unknown-alias-default-psychbadalias/71192990#71192990
   class << self
     alias load unsafe_load
+
+    def load_erb_file(path)
+      YAML.load ERB.new(File.read(path)).result
+    end
   end
 end

lib/bashly/refinements/compose_refinements.rb

@@ -22,7 +22,7 @@ def compose(keyword = 'import')
     end
 
     def safe_load_yaml(path)
-      loaded = YAML.load_file path
+      loaded = YAML.load_erb_file path
       return loaded if loaded.is_a?(Array) || loaded.is_a?(Hash)
 
       raise Bashly::ConfigurationError, "Cannot find a valid YAML in g`#{path}`"

spec/approvals/config/erb

@@ -0,0 +1,10 @@
+---
+commands:
+  before: ok
+  list:
+  - file: import_one.yml
+    erb: CHOP
+  - file: import_two.yml
+    more_imports:
+    - file: last_file.yml
+  after: ok

spec/approvals/examples/dependencies-alt

@@ -14,4 +14,4 @@ args: none
 deps:
 - ${deps[git]} = /usr/bin/git
 - ${deps[http_client]} = /usr/bin/curl
-- ${deps[ruby]} = /home/vagrant/.rbenv/versions/3.1.3/bin/ruby
+- ${deps[ruby]} = /home/vagrant/.rbenv/versions/3.2.2/bin/ruby

spec/approvals/extensions/yaml/load-erb-file

@@ -0,0 +1,7 @@
+---
+commands:
+  pi: 3.14
+  list:
+  - Item 1
+  - Item 2
+  - Item 3

spec/bashly/config_spec.rb

@@ -31,5 +31,13 @@
         expect(subject['commands'].first['loaded']).to eq 'yes indeed'
       end
     end
+
+    context 'when the loaded YAML contains ERB and import directives' do
+      let(:config) { 'spec/fixtures/erb/with_imports.yml' }
+
+      it 'evaluates ERB and imports' do
+        expect(subject.to_yaml).to match_approval('config/erb')
+      end
+    end
   end
 end

spec/bashly/extensions/yaml_spec.rb

@@ -0,0 +1,11 @@
+require 'spec_helper'
+
+describe YAML do
+  describe '::load_erb_file' do
+    let(:path) { 'spec/fixtures/erb/simple.yml' }
+
+    it 'pre-processes the loaded YAML file with ERB' do
+      expect(described_class.load_erb_file(path).to_yaml).to match_approval('extensions/yaml/load-erb-file')
+    end
+  end
+end

spec/fixtures/erb/import_one.yml

@@ -0,0 +1,2 @@
+file: import_one.yml
+erb: <%= 'C1-10P'.gsub('1-1', 'H').gsub('0', 'O') %>

spec/fixtures/erb/import_two.yml

@@ -0,0 +1,3 @@
+file: import_two.yml
+more_imports:
+  - import: spec/fixtures/erb/last_file.yml