Merge pull request #2306 from ptrippett/add-remote-config-file

Add remote config files from http/https urls

CHANGELOG.md

@@ -25,6 +25,7 @@
 * `Lint/LiteralInCondition` warns if a symbol or dynamic symbol is used as a condition. ([@alexdowad][])
 * [#2369](https://github.com/bbatsov/rubocop/issues/2369): `Style/TrailingComma` doesn't add a trailing comma to a multiline method chain which is the only arg to a method call. ([@alexdowad][])
 * `CircularArgumentReference` cop updated to lint for ordinal circular argument references on top of optional keyword arguments. ([@maxjacobson][])
+* Added ability to download shared rubocop config files from remote urls. ([@ptrippett][])
 
 ### Bug Fixes
 
@@ -1687,3 +1688,4 @@
 [@alexdowad]: https://github.com/alexdowad
 [@minustehbare]: https://github.com/minustehbare
 [@tansaku]: https://github.com/tansaku
+[@ptrippett]: https://github.com/ptrippett

Gemfile

@@ -7,6 +7,7 @@ gemspec
 group :test do
   gem 'coveralls', require: false
   gem 'safe_yaml', require: false
+  gem 'webmock', require: false
 end
 
 local_gemfile = 'Gemfile.local'

README.md

@@ -292,6 +292,23 @@ inherit_from:
   - ../conf/.rubocop.yml
 ```
 
+### Inheriting configuration from a remote URL
+
+The optional `inherit_from` directive can contain a full url to a remote
+file. This makes it possible to have common project settings stored on a http
+server and shared between many projects. You can inherit from both remote and
+local files in the same config.
+
+The same inheritance rules apply to remote URLs and inheriting from local
+files where the first file in the list has the lowest precedence and the
+last one has the highest. The format for multiple inheritance using URLs is:
+
+```yaml
+inherit_from:
+  - http://www.example.com/rubocop.yml
+  - ../.rubocop.yml
+```
+
 #### Inheriting configuration from a dependency gem
 
 The optional `inherit_gem` directive is used to include configuration from

lib/rubocop.rb

@@ -347,3 +347,4 @@
 require 'rubocop/cli'
 require 'rubocop/options'
 require 'rubocop/warning'
+require 'rubocop/remote_config'

lib/rubocop/config_loader.rb

@@ -60,15 +60,20 @@ def merge(base_hash, derived_hash)
 
       def base_configs(path, inherit_from)
         configs = Array(inherit_from).compact.map do |f|
-          f = File.expand_path(f, File.dirname(path))
+          if f =~ URI.regexp
+            f = RemoteConfig.new(f).file
+            load_file(f)
+          else
+            f = File.expand_path(f, File.dirname(path))
 
-          if auto_gen_config?
-            next if f.include?(AUTO_GENERATED_FILE)
-            old_auto_config_file_warning if f.include?('rubocop-todo.yml')
-          end
+            if auto_gen_config?
+              next if f.include?(AUTO_GENERATED_FILE)
+              old_auto_config_file_warning if f.include?('rubocop-todo.yml')
+            end
 
-          print 'Inheriting ' if debug?
-          load_file(f)
+            print 'Inheriting ' if debug?
+            load_file(f)
+          end
         end
 
         configs.compact

lib/rubocop/remote_config.rb

@@ -0,0 +1,60 @@
+# encoding: utf-8
+
+require 'net/http'
+
+module RuboCop
+  # Common methods and behaviors for dealing with remote config files.
+  class RemoteConfig
+    CACHE_LIFETIME = 24 * 60 * 60
+
+    def initialize(url)
+      @uri = URI.parse(url)
+    end
+
+    def file
+      return cache_path unless cache_path_expired?
+
+      http = Net::HTTP.new(@uri.hostname, @uri.port)
+      http.use_ssl = true if @uri.instance_of? URI::HTTPS
+
+      request = Net::HTTP::Get.new(@uri.request_uri)
+      if cache_path_exists?
+        request['If-Modified-Since'] = File.stat(cache_path).mtime.rfc2822
+      end
+      response = http.request(request)
+
+      cache_path.tap do |f|
+        if response.is_a?(Net::HTTPSuccess)
+          open f, 'w' do |io|
+            io.write response.body
+          end
+        end
+      end
+    end
+
+    private
+
+    def cache_path
+      ".rubocop-#{cache_name_from_uri}"
+    end
+
+    def cache_path_exists?
+      @cache_path_exists ||= File.exist?(cache_path)
+    end
+
+    def cache_path_expired?
+      return true unless cache_path_exists?
+
+      @cache_path_expired ||= begin
+        file_age = (Time.now - File.stat(cache_path).mtime).to_f
+        (file_age / CACHE_LIFETIME) > 1
+      end
+    end
+
+    def cache_name_from_uri
+      uri = @uri.clone
+      uri.query = nil
+      uri.to_s.gsub!(/[^0-9A-Za-z]/, '-')
+    end
+  end
+end

spec/rubocop/config_loader_spec.rb

@@ -304,6 +304,22 @@
           .to be_superset(expected.to_set)
       end
     end
+
+    context 'when a file inherits from a url' do
+      let(:file_path) { '.rubocop.yml' }
+
+      before do
+        stub_request(:get, /example.com/)
+          .to_return(status: 200, body: "Style/Encoding:\n    Enabled: true")
+
+        create_file('~/.rubocop.yml', [''])
+        create_file(file_path, ['inherit_from: http://example.com/rubocop.yml'])
+      end
+
+      it 'does not fail to load the resulting path' do
+        expect { configuration_from_file }.not_to raise_error
+      end
+    end
   end
 
   describe '.load_file', :isolated_environment do

spec/rubocop/remote_config_spec.rb

@@ -0,0 +1,42 @@
+# encoding: utf-8
+
+require 'spec_helper'
+
+describe RuboCop::RemoteConfig do
+  include FileHelper
+
+  let(:remote_config_url) { 'http://example.com/rubocop.yml' }
+  let(:cached_file_name) { '.rubocop-http---example-com-rubocop-yml' }
+
+  subject(:remote_config) { described_class.new(remote_config_url).file }
+
+  before do
+    stub_request(:get, /example.com/)
+      .to_return(status: 200, body: "Style/Encoding:\n    Enabled: true")
+  end
+
+  after do
+    File.unlink cached_file_name if File.exist? cached_file_name
+  end
+
+  describe '.file' do
+    it 'downloads the file if the file does not exist' do
+      expect(subject).to eq(cached_file_name)
+      expect(File.exist? cached_file_name).to be_truthy
+    end
+
+    it 'does not download the file if cache lifetime has not been reached' do
+      FileUtils.touch cached_file_name, mtime: Time.now - ((60 * 60) * 20)
+
+      expect(subject).to eq(cached_file_name)
+      assert_not_requested :get, remote_config_url
+    end
+
+    it 'downloads the file if cache lifetime has been reached' do
+      FileUtils.touch cached_file_name, mtime: Time.now - ((60 * 60) * 30)
+
+      expect(subject).to eq(cached_file_name)
+      assert_requested :get, remote_config_url
+    end
+  end
+end

spec/spec_helper.rb

@@ -5,6 +5,8 @@
 
 require 'rubocop'
 
+require 'webmock/rspec'
+
 # Requires supporting files with custom matchers and macros, etc,
 # in ./support/ and its subdirectories.
 Dir["#{File.dirname(__FILE__)}/support/**/*.rb"].each { |f| require f }
@@ -48,3 +50,6 @@
 
 # Disable colors in specs
 Rainbow.enabled = false
+
+# Disable network connections
+WebMock.disable_net_connect!