Create a basic CLI for rendering templates

README.md

@@ -40,6 +40,16 @@ Pre-existing copies of files generated by Consult (such as `secrets.yml`, `datab
 
 If this gem is included in a Rails, the templates will render on Rails boot. Configuration or credential changes can be picked up by restarting your app.
 
+### CLI
+
+Render templates on demand with the CLI. By default, this will bypass template TTLs to force rendering and provide verbose output. See `consult --help` for options.
+
+```bash
+$ bundle exec consult
+Consult: Rendered my_config
+Consult: Rendered secrets
+```
+
 ### Configuration
 
 ```yaml

bin/consult

@@ -0,0 +1,7 @@
+#!/usr/bin/env ruby
+
+require_relative '../lib/consult/cli'
+
+cli = Consult::CLI.instance
+cli.parse
+cli.render

consult.gemspec

@@ -20,19 +20,18 @@ Gem::Specification.new do |spec|
   spec.files = `git ls-files -z`.split("\x0").reject do |f|
     f.match(%r{^(test|spec|features)/})
   end
-  spec.bindir        = 'exe'
-  spec.executables   = spec.files.grep(%r{^exe/}) { |f| File.basename(f) }
+  spec.bindir        = 'bin'
+  spec.executables   = ['consult']
   spec.require_paths = ['lib']
 
   spec.add_dependency 'activesupport', '> 4', '< 6'
   spec.add_dependency 'diplomat', '~> 2.0.2'
   spec.add_dependency 'vault', '>= 0.10.0', '< 1.0.0'
 
   spec.add_development_dependency 'bundler', '~> 1.16'
-  spec.add_development_dependency 'byebug'
   spec.add_development_dependency 'guard'
   spec.add_development_dependency 'guard-rspec'
-  spec.add_development_dependency 'pry'
+  spec.add_development_dependency 'pry-byebug'
   spec.add_development_dependency 'rake', '~> 10.0'
   spec.add_development_dependency 'rspec', '~> 3.0'
   spec.add_development_dependency 'simplecov'

lib/consult.rb

@@ -18,16 +18,19 @@ module Consult
   CONSUL_DISK_TOKEN = Pathname.new("#{Dir.home}/.consul-token").freeze
 
   class << self
-    attr_reader :config, :templates
-    def load(config_dir: nil)
+    attr_reader :config, :templates, :force_render
+
+    def load(config_dir: nil, force_render: false, verbose: nil)
       root directory: config_dir
       yaml = root.join('config', 'consult.yml')
 
       @all_config = yaml.exist? ? YAML.safe_load(ERB.new(yaml.read).result, [], [], true).to_h : {}
       @all_config.deep_symbolize_keys!
 
       @config = @all_config[:shared].to_h.deep_merge @all_config[env&.to_sym].to_h
-      @templates = @config[:templates]&.map { |name, config| Template.new(name, config) } || []
+      @templates = @config[:templates]&.map { |name, config| Template.new(name, config.merge(verbose: verbose)) } || []
+
+      @force_render = force_render
 
       configure_consul
       configure_vault
@@ -71,7 +74,7 @@ def env
 
     # Return only the templates that are relevant for the current environment
     def active_templates
-      templates.select(&:should_render?)
+      force_render ? templates : templates.select(&:should_render?)
     end
 
     # Render templates.

lib/consult/cli.rb

@@ -0,0 +1,55 @@
+# frozen_string_literal: true
+
+$stdout.sync = true
+
+require 'singleton'
+require 'optparse'
+
+require_relative '../consult'
+
+module Consult
+  class CLI
+    include Singleton
+
+    attr_reader :opts
+
+    def parse(args = ARGV)
+      @opts = parse_options(args)
+      Consult.load @opts
+    end
+
+    def render
+      Consult.render!
+    end
+
+    def parse_options(argv)
+      opts = {
+        config_dir: Dir.pwd,
+        force_render: true,
+        verbose: true
+      }
+
+      @parser = OptionParser.new do |o|
+        o.on '-d', '--directory=DIR', 'Path to directory containing the config directory' do |arg|
+          opts[:config_dir] = arg
+        end
+
+        o.on '-f', '--[no-]force', TrueClass, 'Ignore template TTLs and force rendering' do |arg|
+          opts[:force_render] = arg
+        end
+
+        o.on '-v', '--quiet', FalseClass, 'Silence output' do |arg|
+          opts[:verbose] = arg
+        end
+      end
+
+      @parser.on_tail "-h", "--help", "Show help" do
+        puts @parser
+        exit 1
+      end
+
+      @parser.parse! argv
+      opts
+    end
+  end
+end

lib/consult/template.rb

@@ -22,6 +22,7 @@ def render(save: true)
       result = renderer.result(binding)
 
       File.open(dest, 'w') { |f| f << result } if save
+      puts "Consult: Rendered #{name}" if verbose?
       result
     rescue StandardError => e
       STDERR.puts "Error rendering template: #{name}"
@@ -55,6 +56,10 @@ def expired?
       dest.mtime < (Time.now - @config[:ttl].to_i)
     end
 
+    def verbose?
+      @config[:verbose]
+    end
+
     def ordered_locations
       @config.keys & LOCATIONS
     end

spec/bin/cli_spec.rb

@@ -0,0 +1,28 @@
+# frozen_string_literal: true
+
+require 'consult/cli'
+
+RSpec.describe Consult::CLI do
+  let(:cli) { Consult::CLI.instance }
+
+  describe 'options' do
+    it 'parses --directory' do
+      options = cli.parse ['--directory', 'spec/support']
+      expect(cli.opts[:config_dir]).to eq 'spec/support'
+    end
+
+    it 'parses --force' do
+      options = cli.parse ['--force']
+      expect(cli.opts[:force_render]).to be true
+    end
+
+    it 'parses --quiet' do
+      options = cli.parse ['--quiet']
+      expect(cli.opts[:verbose]).to be false
+    end
+  end
+
+  it 'renders' do
+    expect {cli.render}.not_to raise_exception
+  end
+end

spec/consult_spec.rb

@@ -27,4 +27,16 @@
       expect(FileUtils.compare_file("spec/support/expected/#{template}", "spec/support/rendered/#{template}")).to be true
     end
   end
+
+  it 'obeys TTLs' do
+    Consult.load config_dir: directory, force_render: false
+    Consult.render!
+    expect(Consult.active_templates).not_to eq(Consult.templates)
+  end
+
+  it 'can force template rendering' do
+    Consult.load config_dir: directory, force_render: true
+    Consult.render!
+    expect(Consult.active_templates).to eq Consult.templates
+  end
 end

spec/lib/template_spec.rb

@@ -49,6 +49,12 @@
     expect(template.should_render?).to be(true)
   end
 
+  it 'supports verbose output' do
+    t = Consult::Template.new 'verbose', config.merge(verbose: true)
+    expect(t.verbose?).to be(true)
+    expect { t.render }.to output(/Consult: Rendered verbose/i).to_stdout_from_any_process
+  end
+
   it 'outputs render failures to stderr' do
     expect { fail_template.render }.to output(/Error rendering template*/).to_stderr_from_any_process
   end