Add port section to CI Image object

In order to implement https://gitlab.com/gitlab-org/gitlab-ee/issues/10179
we need several modifications on the CI config file. We are
adding a new ports section in the default Image object.

Each of these ports will accept: number, protocol and name.

By default this new configuration will be only enabled in
the Web IDE config file.

lib/api/entities.rb

@@ -1389,8 +1389,13 @@ module API
         expose :name, :script, :timeout, :when, :allow_failure
       end
 
+      class Port < Grape::Entity
+        expose :number, :protocol, :name
+      end
+
       class Image < Grape::Entity
         expose :name, :entrypoint
+        expose :ports, using: JobRequest::Port
       end
 
       class Service < Image

lib/gitlab/ci/build/image.rb

@@ -4,7 +4,7 @@ module Gitlab
   module Ci
     module Build
       class Image
-        attr_reader :alias, :command, :entrypoint, :name
+        attr_reader :alias, :command, :entrypoint, :name, :ports
 
         class << self
           def from_image(job)
@@ -26,17 +26,25 @@ module Gitlab
         def initialize(image)
           if image.is_a?(String)
             @name = image
+            @ports = []
           elsif image.is_a?(Hash)
             @alias = image[:alias]
             @command = image[:command]
             @entrypoint = image[:entrypoint]
             @name = image[:name]
+            @ports = build_ports(image).select(&:valid?)
           end
         end
 
         def valid?
           @name.present?
         end
+
+        private
+
+        def build_ports(image)
+          image[:ports].to_a.map { |port| ::Gitlab::Ci::Build::Port.new(port) }
+        end
       end
     end
   end

lib/gitlab/ci/build/port.rb

+# frozen_string_literal: true
+
+module Gitlab
+  module Ci
+    module Build
+      class Port
+        DEFAULT_PORT_NAME = 'default_port'.freeze
+        DEFAULT_PORT_PROTOCOL = 'http'.freeze
+
+        attr_reader :number, :protocol, :name
+
+        def initialize(port)
+          @name = DEFAULT_PORT_NAME
+          @protocol = DEFAULT_PORT_PROTOCOL
+
+          case port
+          when Integer
+            @number = port
+          when Hash
+            @number = port[:number]
+            @protocol = port.fetch(:protocol, @protocol)
+            @name = port.fetch(:name, @name)
+          end
+        end
+
+        def valid?
+          @number.present?
+        end
+      end
+    end
+  end
+end

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

@@ -9,24 +9,24 @@ module Gitlab
         #
         class Image < ::Gitlab::Config::Entry::Node
           include ::Gitlab::Config::Entry::Validatable
+          include ::Gitlab::Config::Entry::Attributable
+          include ::Gitlab::Config::Entry::Configurable
 
-          ALLOWED_KEYS = %i[name entrypoint].freeze
+          ALLOWED_KEYS = %i[name entrypoint ports].freeze
 
           validations do
             validates :config, hash_or_string: true
             validates :config, allowed_keys: ALLOWED_KEYS
+            validates :config, disallowed_keys: %i[ports], unless: :with_image_ports?
 
             validates :name, type: String, presence: true
             validates :entrypoint, array_of_strings: true, allow_nil: true
           end
 
-          def hash?
-            @config.is_a?(Hash)
-          end
+          entry :ports, Entry::Ports,
+            description: 'Ports used expose the image'
 
-          def string?
-            @config.is_a?(String)
-          end
+          attributes :ports
 
           def name
             value[:name]
@@ -42,6 +42,14 @@ module Gitlab
 
             {}
           end
+
+          def with_image_ports?
+            opt(:with_image_ports)
+          end
+
+          def skip_config_hash_validation?
+            true
+          end
         end
       end
     end

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

+# frozen_string_literal: true
+
+module Gitlab
+  module Ci
+    class Config
+      module Entry
+        ##
+        # Entry that represents a configuration of an Image Port.
+        #
+        class Port < ::Gitlab::Config::Entry::Node
+          include ::Gitlab::Config::Entry::Validatable
+
+          ALLOWED_KEYS = %i[number protocol name].freeze
+
+          validations do
+            validates :config, hash_or_integer: true
+            validates :config, allowed_keys: ALLOWED_KEYS
+
+            validates :number, type: Integer, presence: true
+            validates :protocol, type: String, inclusion: { in: %w[http https], message: 'should be http or https' }, allow_blank: true
+            validates :name, type: String, presence: false, allow_nil: true
+          end
+
+          def number
+            value[:number]
+          end
+
+          def protocol
+            value[:protocol]
+          end
+
+          def name
+            value[:name]
+          end
+
+          def value
+            return { number: @config } if integer?
+            return @config if hash?
+
+            {}
+          end
+        end
+      end
+    end
+  end
+end

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

+# frozen_string_literal: true
+
+module Gitlab
+  module Ci
+    class Config
+      module Entry
+        ##
+        # Entry that represents a configuration of the ports of a Docker service.
+        #
+        class Ports < ::Gitlab::Config::Entry::Node
+          include ::Gitlab::Config::Entry::Validatable
+
+          validations do
+            validates :config, type: Array
+            validates :config, port_name_present_and_unique: true
+            validates :config, port_unique: true
+          end
+
+          def compose!(deps = nil)
+            super do
+              @entries = []
+              @config.each do |config|
+                @entries << ::Gitlab::Config::Entry::Factory.new(Entry::Port)
+                  .value(config || {})
+                  .with(key: "port", parent: self, description: "port definition.") # rubocop:disable CodeReuse/ActiveRecord
+                  .create!
+              end
+
+              @entries.each do |entry|
+                entry.compose!(deps)
+              end
+            end
+          end
+
+          def value
+            @entries.map(&:value)
+          end
+
+          def descendants
+            @entries
+          end
+        end
+      end
+    end
+  end
+end

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

@@ -10,16 +10,18 @@ module Gitlab
         class Service < Image
           include ::Gitlab::Config::Entry::Validatable
 
-          ALLOWED_KEYS = %i[name entrypoint command alias].freeze
+          ALLOWED_KEYS = %i[name entrypoint command alias ports].freeze
 
           validations do
             validates :config, hash_or_string: true
             validates :config, allowed_keys: ALLOWED_KEYS
+            validates :config, disallowed_keys: %i[ports], unless: :with_image_ports?
 
             validates :name, type: String, presence: true
             validates :entrypoint, array_of_strings: true, allow_nil: true
             validates :command, array_of_strings: true, allow_nil: true
             validates :alias, type: String, allow_nil: true
+            validates :alias, type: String, presence: true, unless: ->(record) { record.ports.blank? }
           end
 
           def alias

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

@@ -12,6 +12,7 @@ module Gitlab
 
           validations do
             validates :config, type: Array
+            validates :config, services_with_ports_alias_unique: true, if: ->(record) { record.opt(:with_image_ports) }
           end
 
           def compose!(deps = nil)
@@ -20,6 +21,7 @@ module Gitlab
               @config.each do |config|
                 @entries << ::Gitlab::Config::Entry::Factory.new(Entry::Service)
                   .value(config || {})
+                  .with(key: "service", parent: self, description: "service definition.") # rubocop:disable CodeReuse/ActiveRecord
                   .create!
               end
 

lib/gitlab/config/entry/configurable.rb

@@ -21,7 +21,7 @@ module Gitlab
           include Validatable
 
           validations do
-            validates :config, type: Hash
+            validates :config, type: Hash, unless: :skip_config_hash_validation?
           end
         end
 
@@ -30,6 +30,10 @@ module Gitlab
           return unless valid?
 
           self.class.nodes.each do |key, factory|
+            # If we override the config type validation
+            # we can end with different config types like String
+            next unless config.is_a?(Hash)
+
             factory
               .value(config[key])
               .with(key: key, parent: self)
@@ -45,6 +49,10 @@ module Gitlab
         end
         # rubocop: enable CodeReuse/ActiveRecord
 
+        def skip_config_hash_validation?
+          false
+        end
+
         class_methods do
           def nodes
             Hash[(@nodes || {}).map { |key, factory| [key, factory.dup] }]

lib/gitlab/config/entry/factory.rb

@@ -61,7 +61,7 @@ module Gitlab
         end
 
         def fabricate(entry, value = nil)
-          entry.new(value, @metadata).tap do |node|
+          entry.new(value, @metadata) do |node|
             node.key = @attributes[:key]
             node.parent = @attributes[:parent]
             node.default = @attributes[:default]

lib/gitlab/config/entry/node.rb

@@ -17,6 +17,8 @@ module Gitlab
           @metadata = metadata
           @entries = {}
 
+          yield(self) if block_given?
+
           self.class.aspects.to_a.each do |aspect|
             instance_exec(&aspect)
           end
@@ -44,6 +46,12 @@ module Gitlab
           @parent ? @parent.ancestors + [@parent] : []
         end
 
+        def opt(key)
+          opt = metadata[key]
+          opt = @parent.opt(key) if opt.nil? && @parent
+          opt
+        end
+
         def valid?
           errors.none?
         end
@@ -85,6 +93,18 @@ module Gitlab
           "#<#{self.class.name} #{unspecified}{#{key}: #{val.inspect}}>"
         end
 
+        def hash?
+          @config.is_a?(Hash)
+        end
+
+        def string?
+          @config.is_a?(String)
+        end
+
+        def integer?
+          @config.is_a?(Integer)
+        end
+
         def self.default(**)
         end
 

lib/gitlab/config/entry/simplifiable.rb

@@ -19,7 +19,10 @@ module Gitlab
 
           entry = self.class.entry_class(strategy)
 
-          super(@subject = entry.new(config, metadata))
+          @subject = entry.new(config, metadata)
+
+          yield(@subject) if block_given?
+          super(@subject)
         end
 
         def self.strategy(name, **opts)

lib/gitlab/config/entry/validators.rb

@@ -15,6 +15,17 @@ module Gitlab
           end
         end
 
+        class DisallowedKeysValidator < ActiveModel::EachValidator
+          def validate_each(record, attribute, value)
+            present_keys = value.try(:keys).to_a & options[:in]
+
+            if present_keys.any?
+              record.errors.add(attribute, "contains disallowed keys: " +
+                present_keys.join(', '))
+            end
+          end
+        end
+
         class AllowedValuesValidator < ActiveModel::EachValidator
           def validate_each(record, attribute, value)
             unless options[:in].include?(value.to_s)
@@ -186,6 +197,97 @@ module Gitlab
             end
           end
         end
+
+        class PortNamePresentAndUniqueValidator < ActiveModel::EachValidator
+          def validate_each(record, attribute, value)
+            return unless value.is_a?(Array)
+
+            ports_size = value.count
+            return if ports_size <= 1
+
+            named_ports = value.select { |e| e.is_a?(Hash) }.map { |e| e[:name] }.compact.map(&:downcase)
+
+            if ports_size != named_ports.size
+              record.errors.add(attribute, 'when there is more than one port, a unique name should be added')
+            end
+
+            if ports_size != named_ports.uniq.size
+              record.errors.add(attribute, 'each port name must be different')
+            end
+          end
+        end
+
+        class PortUniqueValidator < ActiveModel::EachValidator
+          def validate_each(record, attribute, value)
+            value = ports(value)
+            return unless value.is_a?(Array)
+
+            ports_size = value.count
+            return if ports_size <= 1
+
+            if transform_ports(value).size != ports_size
+              record.errors.add(attribute, 'each port number can only be referenced once')
+            end
+          end
+
+          private
+
+          def ports(current_data)
+            current_data
+          end
+
+          def transform_ports(raw_ports)
+            raw_ports.map do |port|
+              case port
+              when Integer
+                port
+              when Hash
+                port[:number]
+              end
+            end.uniq
+          end
+        end
+
+        class JobPortUniqueValidator < PortUniqueValidator
+          private
+
+          def ports(current_data)
+            return unless current_data.is_a?(Hash)
+
+            (image_ports(current_data) + services_ports(current_data)).compact
+          end
+
+          def image_ports(current_data)
+            return [] unless current_data[:image].is_a?(Hash)
+
+            current_data.dig(:image, :ports).to_a
+          end
+
+          def services_ports(current_data)
+            current_data.dig(:services).to_a.flat_map { |service| service.is_a?(Hash) ? service[:ports] : nil }
+          end
+        end
+
+        class ServicesWithPortsAliasUniqueValidator < ActiveModel::EachValidator
+          def validate_each(record, attribute, value)
+            current_aliases = aliases(value)
+            return if current_aliases.empty?
+
+            unless aliases_unique?(current_aliases)
+              record.errors.add(:config, 'alias must be unique in services with ports')
+            end
+          end
+
+          private
+
+          def aliases(value)
+            value.select { |s| s.is_a?(Hash) && s[:ports] }.pluck(:alias) # rubocop:disable CodeReuse/ActiveRecord
+          end
+
+          def aliases_unique?(aliases)
+            aliases.size == aliases.uniq.size
+          end
+        end
       end
     end
   end

spec/lib/api/entities/job_request/image_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe API::Entities::JobRequest::Image do
+  let(:ports) { [{ number: 80, protocol: 'http', name: 'name' }]}
+  let(:image) { double(name: 'image_name', entrypoint: ['foo'], ports: ports)}
+  let(:entity) { described_class.new(image) }
+
+  subject { entity.as_json }
+
+  it 'returns the image name' do
+    expect(subject[:name]).to eq 'image_name'
+  end
+
+  it 'returns the entrypoint' do
+    expect(subject[:entrypoint]).to eq ['foo']
+  end
+
+  it 'returns the ports' do
+    expect(subject[:ports]).to eq ports
+  end
+
+  context 'when the ports param is nil' do
+    let(:ports) { nil }
+
+    it 'does not return the ports' do
+      expect(subject[:ports]).to be_nil
+    end
+  end
+end

spec/lib/api/entities/job_request/port_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe ::API::Entities::JobRequest::Port do
+  let(:port) { double(number: 80, protocol: 'http', name: 'name')}
+  let(:entity) { described_class.new(port) }
+
+  subject { entity.as_json }
+
+  it 'returns the port number' do
+    expect(subject[:number]).to eq 80
+  end
+
+  it 'returns if the port protocol' do
+    expect(subject[:protocol]).to eq 'http'
+  end
+
+  it 'returns the port name' do
+    expect(subject[:name]).to eq 'name'
+  end
+end

spec/lib/gitlab/ci/build/image_spec.rb

@@ -18,11 +18,16 @@ describe Gitlab::Ci::Build::Image do
         it 'populates fabricated object with the proper name attribute' do
           expect(subject.name).to eq(image_name)
         end
+
+        it 'does not populate the ports' do
+          expect(subject.ports).to be_empty
+        end
       end
 
       context 'when image is defined as hash' do
         let(:entrypoint) { '/bin/sh' }
-        let(:job) { create(:ci_build, options: { image: { name: image_name, entrypoint: entrypoint } } ) }
+
+        let(:job) { create(:ci_build, options: { image: { name: image_name, entrypoint: entrypoint, ports: [80] } } ) }
 
         it 'fabricates an object of the proper class' do
           is_expected.to be_kind_of(described_class)
@@ -32,6 +37,13 @@ describe Gitlab::Ci::Build::Image do
           expect(subject.name).to eq(image_name)
           expect(subject.entrypoint).to eq(entrypoint)
         end
+
+        it 'populates the ports' do
+          port = subject.ports.first
+          expect(port.number).to eq 80
+          expect(port.protocol).to eq 'http'
+          expect(port.name).to eq 'default_port'
+        end
       end
 
       context 'when image name is empty' do
@@ -67,6 +79,10 @@ describe Gitlab::Ci::Build::Image do
           expect(subject.first).to be_kind_of(described_class)
           expect(subject.first.name).to eq(service_image_name)
         end
+
+        it 'does not populate the ports' do
+          expect(subject.first.ports).to be_empty
+        end
       end
 
       context 'when service is defined as hash' do
@@ -75,7 +91,7 @@ describe Gitlab::Ci::Build::Image do
         let(:service_command) { 'sleep 30' }
         let(:job) do
           create(:ci_build, options: { services: [{ name: service_image_name, entrypoint: service_entrypoint,
-                                                    alias: service_alias, command: service_command }] })
+                                                    alias: service_alias, command: service_command, ports: [80] }] })
         end
 
         it 'fabricates an non-empty array of objects' do
@@ -89,6 +105,11 @@ describe Gitlab::Ci::Build::Image do
           expect(subject.first.entrypoint).to eq(service_entrypoint)
           expect(subject.first.alias).to eq(service_alias)
           expect(subject.first.command).to eq(service_command)
+
+          port = subject.first.ports.first
+          expect(port.number).to eq 80
+          expect(port.protocol).to eq 'http'
+          expect(port.name).to eq 'default_port'
         end
       end
 

spec/lib/gitlab/ci/build/port_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Gitlab::Ci::Build::Port do
+  subject { described_class.new(port) }
+
+  context 'when port is defined as an integer' do
+    let(:port) { 80 }
+
+    it 'populates the object' do
+      expect(subject.number).to eq 80
+      expect(subject.protocol).to eq described_class::DEFAULT_PORT_PROTOCOL
+      expect(subject.name).to eq described_class::DEFAULT_PORT_NAME
+    end
+  end
+
+  context 'when port is defined as hash' do
+    let(:port) { { number: 80, protocol: 'https', name: 'port_name' } }
+
+    it 'populates the object' do
+      expect(subject.number).to eq 80
+      expect(subject.protocol).to eq 'https'
+      expect(subject.name).to eq 'port_name'
+    end
+  end
+end

spec/lib/gitlab/ci/config/entry/image_spec.rb

@@ -35,6 +35,12 @@ describe Gitlab::Ci::Config::Entry::Image do
         expect(entry.entrypoint).to be_nil
       end
     end
+
+    describe '#ports' do
+      it "returns image's ports" do
+        expect(entry.ports).to be_nil
+      end
+    end
   end
 
   context 'when configuration is a hash' do
@@ -69,6 +75,38 @@ describe Gitlab::Ci::Config::Entry::Image do
         expect(entry.entrypoint).to eq %w(/bin/sh run)
       end
     end
+
+    context 'when configuration has ports' do
+      let(:ports) { [{ number: 80, protocol: 'http', name: 'foobar' }] }
+      let(:config) { { name: 'ruby:2.2', entrypoint: %w(/bin/sh run), ports: ports } }
+      let(:entry) { described_class.new(config, { with_image_ports: image_ports }) }
+      let(:image_ports) { false }
+
+      context 'when with_image_ports metadata is not enabled' do
+        describe '#valid?' do
+          it 'is not valid' do
+            expect(entry).not_to be_valid
+            expect(entry.errors).to include("image config contains disallowed keys: ports")
+          end
+        end
+      end
+
+      context 'when with_image_ports metadata is enabled' do
+        let(:image_ports) { true }
+
+        describe '#valid?' do
+          it 'is valid' do
+            expect(entry).to be_valid
+          end
+        end
+
+        describe '#ports' do
+          it "returns image's ports" do
+            expect(entry.ports).to eq ports
+          end
+        end
+      end
+    end
   end
 
   context 'when entry value is not correct' do
@@ -76,8 +114,8 @@ describe Gitlab::Ci::Config::Entry::Image do
 
     describe '#errors' do
       it 'saves errors' do
-        expect(entry.errors)
-          .to include 'image config should be a hash or a string'
+        expect(entry.errors.first)
+          .to match /config should be a hash or a string/
       end
     end
 
@@ -93,8 +131,8 @@ describe Gitlab::Ci::Config::Entry::Image do
 
     describe '#errors' do
       it 'saves errors' do
-        expect(entry.errors)
-            .to include 'image config contains unknown keys: non_existing'
+        expect(entry.errors.first)
+          .to match /config contains unknown keys: non_existing/
       end
     end
 

spec/lib/gitlab/ci/config/entry/port_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Gitlab::Ci::Config::Entry::Port do
+  let(:entry) { described_class.new(config) }
+
+  before do
+    entry.compose!
+  end
+
+  context 'when configuration is a string' do
+    let(:config) { 80 }
+
+    describe '#valid?' do
+      it 'is valid' do
+        expect(entry).to be_valid
+      end
+    end
+
+    describe '#value' do
+      it 'returns valid hash' do
+        expect(entry.value).to eq(number: 80)
+      end
+    end
+
+    describe '#number' do
+      it "returns port number" do
+        expect(entry.number).to eq 80
+      end
+    end
+
+    describe '#protocol' do
+      it "is nil" do
+        expect(entry.protocol).to be_nil
+      end
+    end
+
+    describe '#name' do
+      it "is nil" do
+        expect(entry.name).to be_nil
+      end
+    end
+  end
+
+  context 'when configuration is a hash' do
+    context 'with the complete hash' do
+      let(:config) do
+        { number: 80,
+          protocol: 'http',
+          name:  'foobar' }
+      end
+
+      describe '#valid?' do
+        it 'is valid' do
+          expect(entry).to be_valid
+        end
+      end
+
+      describe '#value' do
+        it 'returns valid hash' do
+          expect(entry.value).to eq config
+        end
+      end
+
+      describe '#number' do
+        it "returns port number" do
+          expect(entry.number).to eq 80
+        end
+      end
+
+      describe '#protocol' do
+        it "returns port protocol" do
+          expect(entry.protocol).to eq 'http'
+        end
+      end
+
+      describe '#name' do
+        it "returns port name" do
+          expect(entry.name).to eq 'foobar'
+        end
+      end
+    end
+
+    context 'with only the port number' do
+      let(:config) { { number: 80 } }
+
+      describe '#valid?' do
+        it 'is valid' do
+          expect(entry).to be_valid
+        end
+      end
+
+      describe '#value' do
+        it 'returns valid hash' do
+          expect(entry.value).to eq(number: 80)
+        end
+      end
+
+      describe '#number' do
+        it "returns port number" do
+          expect(entry.number).to eq 80
+        end
+      end
+
+      describe '#protocol' do
+        it "is nil" do
+          expect(entry.protocol).to be_nil
+        end
+      end
+
+      describe '#name' do
+        it "is nil" do
+          expect(entry.name).to be_nil
+        end
+      end
+    end
+
+    context 'without the number' do
+      let(:config) { { protocol: 'http' } }
+
+      describe '#valid?' do
+        it 'is not valid' do
+          expect(entry).not_to be_valid
+        end
+      end
+    end
+  end
+
+  context 'when configuration is invalid' do
+    let(:config) { '80' }
+
+    describe '#valid?' do
+      it 'is valid' do
+        expect(entry).not_to be_valid
+      end
+    end
+  end
+
+  context 'when protocol' do
+    let(:config) { { number: 80, protocol: protocol, name: 'foobar' } }
+
+    context 'is http' do
+      let(:protocol) { 'http' }
+
+      describe '#valid?' do
+        it 'is valid' do
+          expect(entry).to be_valid
+        end
+      end
+    end
+
+    context 'is https' do
+      let(:protocol) { 'https' }
+
+      describe '#valid?' do
+        it 'is valid' do
+          expect(entry).to be_valid
+        end
+      end
+    end
+
+    context 'is neither http nor https' do
+      let(:protocol) { 'foo' }
+
+      describe '#valid?' do
+        it 'is invalid' do
+          expect(entry.errors).to include("port protocol should be http or https")
+        end
+      end
+    end
+  end
+end

spec/lib/gitlab/ci/config/entry/ports_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Gitlab::Ci::Config::Entry::Ports do
+  let(:entry) { described_class.new(config) }
+
+  before do
+    entry.compose!
+  end
+
+  context 'when configuration is valid' do
+    let(:config) { [{ number: 80, protocol: 'http', name: 'foobar' }] }
+
+    describe '#valid?' do
+      it 'is valid' do
+        expect(entry).to be_valid
+      end
+    end
+
+    describe '#value' do
+      it 'returns valid array' do
+        expect(entry.value).to eq(config)
+      end
+    end
+  end
+
+  context 'when configuration is invalid' do
+    let(:config) { 'postgresql:9.5' }
+
+    describe '#valid?' do
+      it 'is invalid' do
+        expect(entry).not_to be_valid
+      end
+    end
+
+    context 'when any of the ports' do
+      before do
+        expect(entry).not_to be_valid
+        expect(entry.errors.count).to eq 1
+      end
+
+      context 'have the same name' do
+        let(:config) do
+          [{ number: 80, protocol: 'http', name: 'foobar' },
+           { number: 81, protocol: 'http', name: 'foobar' }]
+        end
+
+        describe '#valid?' do
+          it 'is invalid' do
+            expect(entry.errors.first).to match /each port name must be different/
+          end
+        end
+      end
+
+      context 'have the same port' do
+        let(:config) do
+          [{ number: 80, protocol: 'http', name: 'foobar' },
+           { number: 80, protocol: 'http', name: 'foobar1' }]
+        end
+
+        describe '#valid?' do
+          it 'is invalid' do
+            expect(entry.errors.first).to match /each port number can only be referenced once/
+          end
+        end
+      end
+    end
+  end
+end

spec/lib/gitlab/ci/config/entry/service_spec.rb

@@ -39,6 +39,12 @@ describe Gitlab::Ci::Config::Entry::Service do
         expect(entry.command).to be_nil
       end
     end
+
+    describe '#ports' do
+      it "returns service's ports" do
+        expect(entry.ports).to be_nil
+      end
+    end
   end
 
   context 'when configuration is a hash' do
@@ -81,6 +87,40 @@ describe Gitlab::Ci::Config::Entry::Service do
         expect(entry.entrypoint).to eq %w(/bin/sh run)
       end
     end
+
+    context 'when configuration has ports' do
+      let(:ports) { [{ number: 80, protocol: 'http', name: 'foobar' }] }
+      let(:config) do
+        { name: 'postgresql:9.5', alias: 'db', command: %w(cmd run), entrypoint: %w(/bin/sh run), ports: ports }
+      end
+      let(:entry) { described_class.new(config, { with_image_ports: image_ports }) }
+      let(:image_ports) { false }
+
+      context 'when with_image_ports metadata is not enabled' do
+        describe '#valid?' do
+          it 'is not valid' do
+            expect(entry).not_to be_valid
+            expect(entry.errors).to include("service config contains disallowed keys: ports")
+          end
+        end
+      end
+
+      context 'when with_image_ports metadata is enabled' do
+        let(:image_ports) { true }
+
+        describe '#valid?' do
+          it 'is valid' do
+            expect(entry).to be_valid
+          end
+        end
+
+        describe '#ports' do
+          it "returns image's ports" do
+            expect(entry.ports).to eq ports
+          end
+        end
+      end
+    end
   end
 
   context 'when entry value is not correct' do
@@ -88,8 +128,8 @@ describe Gitlab::Ci::Config::Entry::Service do
 
     describe '#errors' do
       it 'saves errors' do
-        expect(entry.errors)
-            .to include 'service config should be a hash or a string'
+        expect(entry.errors.first)
+            .to match /config should be a hash or a string/
       end
     end
 
@@ -105,8 +145,8 @@ describe Gitlab::Ci::Config::Entry::Service do
 
     describe '#errors' do
       it 'saves errors' do
-        expect(entry.errors)
-            .to include 'service config contains unknown keys: non_existing'
+        expect(entry.errors.first)
+            .to match /config contains unknown keys: non_existing/
       end
     end
 
@@ -116,4 +156,26 @@ describe Gitlab::Ci::Config::Entry::Service do
       end
     end
   end
+
+  context 'when service has ports' do
+    let(:ports) { [{ number: 80, protocol: 'http', name: 'foobar' }] }
+    let(:config) do
+      { name: 'postgresql:9.5', command: %w(cmd run), entrypoint: %w(/bin/sh run), ports: ports }
+    end
+
+    it 'alias field is mandatory' do
+      expect(entry).not_to be_valid
+      expect(entry.errors).to include("service alias can't be blank")
+    end
+  end
+
+  context 'when service does not have ports' do
+    let(:config) do
+      { name: 'postgresql:9.5', alias: 'db', command: %w(cmd run), entrypoint: %w(/bin/sh run) }
+    end
+
+    it 'alias field is optional' do
+      expect(entry).to be_valid
+    end
+  end
 end

spec/lib/gitlab/ci/config/entry/services_spec.rb

@@ -32,4 +32,91 @@ describe Gitlab::Ci::Config::Entry::Services do
       end
     end
   end
+
+  context 'when configuration has ports' do
+    let(:ports) { [{ number: 80, protocol: 'http', name: 'foobar' }] }
+    let(:config) { ['postgresql:9.5', { name: 'postgresql:9.1', alias: 'postgres_old', ports: ports }] }
+    let(:entry) { described_class.new(config, { with_image_ports: image_ports }) }
+    let(:image_ports) { false }
+
+    context 'when with_image_ports metadata is not enabled' do
+      describe '#valid?' do
+        it 'is not valid' do
+          expect(entry).not_to be_valid
+          expect(entry.errors).to include("service config contains disallowed keys: ports")
+        end
+      end
+    end
+
+    context 'when with_image_ports metadata is enabled' do
+      let(:image_ports) { true }
+
+      describe '#valid?' do
+        it 'is valid' do
+          expect(entry).to be_valid
+        end
+      end
+
+      describe '#value' do
+        it 'returns valid array' do
+          expect(entry.value).to eq([{ name: 'postgresql:9.5' }, { name: 'postgresql:9.1', alias: 'postgres_old', ports: ports }])
+        end
+      end
+
+      describe 'services alias' do
+        context 'when they are not unique' do
+          let(:config) do
+            ['postgresql:9.5',
+             { name: 'postgresql:9.1', alias: 'postgres_old', ports: [80] },
+             { name: 'ruby', alias: 'postgres_old', ports: [81] }]
+          end
+
+          describe '#valid?' do
+            it 'is invalid' do
+              expect(entry).not_to be_valid
+              expect(entry.errors).to include("services config alias must be unique in services with ports")
+            end
+          end
+        end
+
+        context 'when they are unique' do
+          let(:config) do
+            ['postgresql:9.5',
+             { name: 'postgresql:9.1', alias: 'postgres_old', ports: [80] },
+             { name: 'ruby', alias: 'ruby', ports: [81] }]
+          end
+
+          describe '#valid?' do
+            it 'is valid' do
+              expect(entry).to be_valid
+            end
+          end
+        end
+
+        context 'when one of the duplicated alias is in a service without ports' do
+          let(:config) do
+            ['postgresql:9.5',
+             { name: 'postgresql:9.1', alias: 'postgres_old', ports: [80] },
+             { name: 'ruby', alias: 'postgres_old' }]
+          end
+
+          it 'is valid' do
+            expect(entry).to be_valid
+          end
+        end
+
+        context 'when there are not any ports' do
+          let(:config) do
+            ['postgresql:9.5',
+             { name: 'postgresql:9.1', alias: 'postgres_old' },
+             { name: 'ruby', alias: 'postgres_old' }]
+          end
+
+          it 'is valid' do
+            expect(entry).to be_valid
+          end
+        end
+      end
+    end
+  end
 end

spec/lib/gitlab/ci/config_spec.rb

@@ -123,6 +123,63 @@ describe Gitlab::Ci::Config do
         )
       end
     end
+
+    context 'when ports have been set' do
+      context 'in the main image' do
+        let(:yml) do
+          <<-EOS
+            image:
+              name: ruby:2.2
+              ports:
+                - 80
+          EOS
+        end
+
+        it 'raises an error' do
+          expect(config.errors).to include("image config contains disallowed keys: ports")
+        end
+      end
+
+      context 'in the job image' do
+        let(:yml) do
+          <<-EOS
+            image: ruby:2.2
+
+            test:
+              script: rspec
+              image:
+                name: ruby:2.2
+                ports:
+                  - 80
+          EOS
+        end
+
+        it 'raises an error' do
+          expect(config.errors).to include("jobs:test:image config contains disallowed keys: ports")
+        end
+      end
+
+      context 'in the services' do
+        let(:yml) do
+          <<-EOS
+            image: ruby:2.2
+
+            test:
+              script: rspec
+              image: ruby:2.2
+              services:
+                - name: test
+                  alias: test
+                  ports:
+                    - 80
+          EOS
+        end
+
+        it 'raises an error' do
+          expect(config.errors).to include("jobs:test:services:service config contains disallowed keys: ports")
+        end
+      end
+    end
   end
 
   context "when using 'include' directive" do

spec/lib/gitlab/ci/yaml_processor_spec.rb

@@ -1233,7 +1233,7 @@ module Gitlab
           config = YAML.dump({ services: [10, "test"], rspec: { script: "test" } })
           expect do
             Gitlab::Ci::YamlProcessor.new(config)
-          end.to raise_error(Gitlab::Ci::YamlProcessor::ValidationError, "service config should be a hash or a string")
+          end.to raise_error(Gitlab::Ci::YamlProcessor::ValidationError, "services:service config should be a hash or a string")
         end
 
         it "returns errors if job services parameter is not an array" do
@@ -1247,7 +1247,7 @@ module Gitlab
           config = YAML.dump({ rspec: { script: "test", services: [10, "test"] } })
           expect do
             Gitlab::Ci::YamlProcessor.new(config)
-          end.to raise_error(Gitlab::Ci::YamlProcessor::ValidationError, "service config should be a hash or a string")
+          end.to raise_error(Gitlab::Ci::YamlProcessor::ValidationError, "jobs:rspec:services:service config should be a hash or a string")
         end
 
         it "returns error if job configuration is invalid" do

spec/requests/api/runner_spec.rb

@@ -470,11 +470,11 @@ describe API::Runner, :clean_gitlab_redis_shared_state do
             expect(json_response['token']).to eq(job.token)
             expect(json_response['job_info']).to eq(expected_job_info)
             expect(json_response['git_info']).to eq(expected_git_info)
-            expect(json_response['image']).to eq({ 'name' => 'ruby:2.1', 'entrypoint' => '/bin/sh' })
+            expect(json_response['image']).to eq({ 'name' => 'ruby:2.1', 'entrypoint' => '/bin/sh', 'ports' => [] })
             expect(json_response['services']).to eq([{ 'name' => 'postgres', 'entrypoint' => nil,
-                                                       'alias' => nil, 'command' => nil },
+                                                       'alias' => nil, 'command' => nil, 'ports' => [] },
                                                      { 'name' => 'docker:stable-dind', 'entrypoint' => '/bin/sh',
-                                                       'alias' => 'docker', 'command' => 'sleep 30' }])
+                                                       'alias' => 'docker', 'command' => 'sleep 30', 'ports' => [] }])
             expect(json_response['steps']).to eq(expected_steps)
             expect(json_response['artifacts']).to eq(expected_artifacts)
             expect(json_response['cache']).to eq(expected_cache)
@@ -853,6 +853,56 @@ describe API::Runner, :clean_gitlab_redis_shared_state do
           end
         end
 
+        describe 'port support' do
+          let(:job) { create(:ci_build, pipeline: pipeline, options: options) }
+
+          context 'when job image has ports' do
+            let(:options) do
+              {
+                image: {
+                  name: 'ruby',
+                  ports: [80]
+                },
+                services: ['mysql']
+              }
+            end
+
+            it 'returns the image ports' do
+              request_job
+
+              expect(response).to have_http_status(:created)
+              expect(json_response).to include(
+                'id' => job.id,
+                'image' => a_hash_including('name' => 'ruby', 'ports' => [{ 'number' => 80, 'protocol' => 'http', 'name' => 'default_port' }]),
+                'services' => all(a_hash_including('name' => 'mysql')))
+            end
+          end
+
+          context 'when job services settings has ports' do
+            let(:options) do
+              {
+                image: 'ruby',
+                services: [
+                  {
+                    name: 'tomcat',
+                    ports: [{ number: 8081, protocol: 'http', name: 'custom_port' }]
+                  }
+                ]
+              }
+            end
+
+            it 'returns the service ports' do
+              request_job
+
+              expect(response).to have_http_status(:created)
+              expect(json_response).to include(
+                'id' => job.id,
+                'image' => a_hash_including('name' => 'ruby'),
+                'services' => all(a_hash_including('name' => 'tomcat', 'ports' => [{ 'number' => 8081, 'protocol' => 'http', 'name' => 'custom_port' }])))
+            end
+          end
+        end
+
         def request_job(token = runner.token, **params)
           new_params = params.merge(token: token, last_update: last_update)
           post api('/jobs/request'), params: new_params, headers: { 'User-Agent' => user_agent }

spec/services/ci/create_pipeline_service_spec.rb

@@ -306,6 +306,56 @@ describe Ci::CreatePipelineService do
 
         it_behaves_like 'a failed pipeline'
       end
+
+      context 'when config has ports' do
+        context 'in the main image' do
+          let(:ci_yaml) do
+            <<-EOS
+              image:
+                name: ruby:2.2
+                ports:
+                  - 80
+            EOS
+          end
+
+          it_behaves_like 'a failed pipeline'
+        end
+
+        context 'in the job image' do
+          let(:ci_yaml) do
+            <<-EOS
+              image: ruby:2.2
+
+              test:
+                script: rspec
+                image:
+                  name: ruby:2.2
+                  ports:
+                    - 80
+            EOS
+          end
+
+          it_behaves_like 'a failed pipeline'
+        end
+
+        context 'in the service' do
+          let(:ci_yaml) do
+            <<-EOS
+              image: ruby:2.2
+
+              test:
+                script: rspec
+                image: ruby:2.2
+                services:
+                  - name: test
+                    ports:
+                      - 80
+            EOS
+          end
+
+          it_behaves_like 'a failed pipeline'
+        end
+      end
     end
 
     context 'when commit contains a [ci skip] directive' do