Implement CI configuration nodes tree processing

lib/gitlab/ci/config/node/before_script.rb

@@ -3,8 +3,11 @@ module Gitlab
     class Config
       module Node
         class BeforeScript < Entry
-          def leaf?
-            true
+          def keys
+            {}
+          end
+
+          def validate!
           end
         end
       end

lib/gitlab/ci/config/node/entry.rb

@@ -3,14 +3,32 @@ module Gitlab
     class Config
       module Node
         class Entry
+          attr_reader :hash, :config, :parent, :nodes, :errors
+
           def initialize(hash, config, parent = nil)
             @hash = hash
             @config = config
             @parent = parent
+            @nodes = {}
+            @errors = []
+          end
+
+          def process!
+            keys.each_pair do |key, entry|
+              next unless hash.include?(key)
+              @nodes[key] = entry.new(hash[key], config, self)
+            end
+
+            @nodes.values.each(&:process!)
+            @nodes.values.each(&:validate!)
+          end
+
+          def keys
+            raise NotImplementedError
           end
 
-          def allowed_keys
-            []
+          def validate!
+            raise NotImplementedError
           end
         end
       end

lib/gitlab/ci/config/node/global.rb

@@ -3,6 +3,9 @@ module Gitlab
     class Config
       module Node
         class Global < Entry
+          def keys
+            { before_script: BeforeScript }
+          end
         end
       end
     end

spec/lib/gitlab/ci/config/node/before_script_spec.rb

@@ -2,10 +2,4 @@ require 'spec_helper'
 
 describe Gitlab::Ci::Config::Node::BeforeScript do
   let(:entry) { described_class.new(hash, config) }
-
-  describe '#leaf?' do
-    it 'is a leaf entry' do
-      expect(entry).to be_leaf
-    end
-  end
 end

spec/lib/gitlab/ci/config/node/global_spec.rb

 require 'spec_helper'
 
 describe Gitlab::Ci::Config::Node::Global do
+  let(:global) { described_class.new(hash, config) }
+  let(:config) { double('Config') }
 
+  describe '#keys' do
+    it 'can contain global config keys' do
+      expect(global.keys).to include :before_script
+    end
+  end
+
+  context 'when hash is valid' do
+    let(:hash) do
+      { before_script: ['ls', 'pwd'] }
+    end
+
+    describe '#process!' do
+      before { global.process! }
+
+      it 'creates nodes hash' do
+        expect(global.nodes).to be_a Hash
+      end
+
+      it 'creates node object for each entry' do
+        expect(global.nodes.count).to eq 1
+      end
+
+      it 'creates node object using valid class' do
+        expect(global.nodes[:before_script])
+          .to be_an_instance_of Gitlab::Ci::Config::Node::BeforeScript
+      end
+    end
+  end
 end