Allow to include templates

This rewrites a syntax to allow include of templates.
This also normalises the syntax used by include: feature

changelogs/unreleased/include-templates.yml

+---
+title: Allow to include templates in gitlab-ci.yml
+merge_request: 23495
+author:
+type: added

doc/ci/yaml/README.md

@@ -1649,6 +1649,7 @@ test:
 > Behaviour expanded in GitLab 10.8 to allow more flexible overriding.
 > [Moved](https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/21603)
 to GitLab Core in 11.4
+> In GitLab 11.7, support for including [GitLab-supplied templates](https://gitlab.com/gitlab-org/gitlab-ce/tree/master/lib/gitlab/ci/templates) directly [was added](https://gitlab.com/gitlab-org/gitlab-ce/issues/53445).
 
 Using the `include` keyword, you can allow the inclusion of external YAML files.
 
@@ -1688,6 +1689,13 @@ are both valid cases:
 include: '/templates/.after-script-template.yml'
 ```
 
+```yaml
+# Single string
+
+include:
+  file: '/templates/.after-script-template.yml'
+```
+
 ```yaml
 # Array
 
@@ -1696,9 +1704,27 @@ include:
   - '/templates/.after-script-template.yml'
 ```
 
+```yaml
+# Array mixed syntax
+
+include:
+  - 'https://gitlab.com/awesome-project/raw/master/.before-script-template.yml'
+  - '/templates/.after-script-template.yml'
+  - template: Auto-DevOps.gitlab-ci.yml
+```
+
+```yaml
+# Array
+
+include:
+  - remote: 'https://gitlab.com/awesome-project/raw/master/.before-script-template.yml'
+  - local: '/templates/.after-script-template.yml'
+  - template: Auto-DevOps.gitlab-ci.yml
+```
+
 ---
 
-`include` supports two types of files:
+`include` supports three types of files:
 
 - **local** to the same repository, referenced by using full paths in the same
   repository, with `/` being the root directory. For example:
@@ -1708,6 +1734,14 @@ include:
     include: '/templates/.gitlab-ci-template.yml'
     ```
 
+    Or using:
+
+    ```yaml
+    # Within the repository
+    include:
+      local: '/templates/.gitlab-ci-template.yml'
+    ```
+
     NOTE: **Note:**
     You can only use files that are currently tracked by Git on the same branch
     your configuration file is. In other words, when using a **local file**, make
@@ -1720,9 +1754,18 @@ include:
   using the full URL. For example:
 
     ```yaml
+    # File sourced from outside repository
     include: 'https://gitlab.com/awesome-project/raw/master/.gitlab-ci-template.yml'
     ```
 
+    Or using:
+
+    ```yaml
+    # File sourced from outside repository
+    include:
+      remote: 'https://gitlab.com/awesome-project/raw/master/.gitlab-ci-template.yml'
+    ```
+
     NOTE: **Note:**
     The remote file must be publicly accessible through a simple GET request, as we don't support authentication schemas in the remote URL.
 
@@ -1731,6 +1774,17 @@ include:
     you may need to enable the **Allow requests to the local network from hooks and services** checkbox
     located in the **Settings > Network > Outbound requests** section within the **Admin area**.
 
+- **template** included with GitLab. For example:
+
+    ```yaml
+    # File sourced from GitLab's template collection
+    include:
+      template: Auto-DevOps.gitlab-ci.yml
+    ```
+
+    NOTE: **Note:**
+    Templates included this way are sourced from [lib/gitlab/ci/templates](https://gitlab.com/gitlab-org/gitlab-ce/tree/master/lib/gitlab/ci/templates).
+
 ---
 
 

lib/gitlab/ci/config.rb

@@ -83,7 +83,7 @@ module Gitlab
 
       def process_external_files(config, project, opts)
         sha = opts.fetch(:sha) { project.repository.root_ref_sha }
-        Config::External::Processor.new(config, project, sha).perform
+        Config::External::Processor.new(config, project: project, sha: sha).perform
       end
     end
   end

lib/gitlab/ci/config/external/file/base.rb

@@ -8,20 +8,26 @@ module Gitlab
           class Base
             include Gitlab::Utils::StrongMemoize
 
-            attr_reader :location, :opts, :errors
+            attr_reader :location, :params, :context, :errors
 
             YAML_WHITELIST_EXTENSION = /.+\.(yml|yaml)$/i.freeze
 
-            def initialize(location, opts = {})
-              @location = location
-              @opts = opts
+            Context = Struct.new(:project, :sha)
+
+            def initialize(params, context)
+              @params = params
+              @context = context
               @errors = []
 
               validate!
             end
 
+            def matching?
+              location.present?
+            end
+
             def invalid_extension?
-              !::File.basename(location).match(YAML_WHITELIST_EXTENSION)
+              location.nil? || !::File.basename(location).match?(YAML_WHITELIST_EXTENSION)
             end
 
             def valid?

lib/gitlab/ci/config/external/file/local.rb

@@ -8,11 +8,8 @@ module Gitlab
           class Local < Base
             include Gitlab::Utils::StrongMemoize
 
-            attr_reader :project, :sha
-
-            def initialize(location, opts = {})
-              @project = opts.fetch(:project)
-              @sha = opts.fetch(:sha)
+            def initialize(params, context)
+              @location = params[:local]
 
               super
             end
@@ -32,7 +29,7 @@ module Gitlab
             end
 
             def fetch_local_content
-              project.repository.blob_data_at(sha, location)
+              context.project.repository.blob_data_at(context.sha, location)
             end
           end
         end

lib/gitlab/ci/config/external/file/remote.rb

@@ -8,6 +8,12 @@ module Gitlab
           class Remote < Base
             include Gitlab::Utils::StrongMemoize
 
+            def initialize(params, context)
+              @location = params[:remote]
+
+              super
+            end
+
             def content
               strong_memoize(:content) { fetch_remote_content }
             end

lib/gitlab/ci/config/external/file/template.rb

+# frozen_string_literal: true
+
+module Gitlab
+  module Ci
+    class Config
+      module External
+        module File
+          class Template < Base
+            attr_reader :location, :project
+
+            SUFFIX = '.gitlab-ci.yml'.freeze
+
+            def initialize(params, context)
+              @location = params[:template]
+
+              super
+            end
+
+            def content
+              strong_memoize(:content) { fetch_template_content }
+            end
+
+            private
+
+            def validate_location!
+              super
+
+              unless template_name_valid?
+                errors.push("Template file `#{location}` is not a valid location!")
+              end
+            end
+
+            def template_name
+              return unless template_name_valid?
+
+              location.first(-SUFFIX.length)
+            end
+
+            def template_name_valid?
+              location.to_s.end_with?(SUFFIX)
+            end
+
+            def fetch_template_content
+              Gitlab::Template::GitlabCiYmlTemplate.find(template_name, project)&.content
+            end
+          end
+        end
+      end
+    end
+  end
+end

lib/gitlab/ci/config/external/mapper.rb

@@ -5,25 +5,63 @@ module Gitlab
     class Config
       module External
         class Mapper
-          def initialize(values, project, sha)
-            @locations = Array(values.fetch(:include, []))
+          include Gitlab::Utils::StrongMemoize
+
+          FILE_CLASSES = [
+            External::File::Remote,
+            External::File::Template,
+            External::File::Local
+          ].freeze
+
+          AmbigiousSpecificationError = Class.new(StandardError)
+
+          def initialize(values, project:, sha:)
+            @locations = Array.wrap(values.fetch(:include, []))
             @project = project
             @sha = sha
           end
 
           def process
-            locations.map { |location| build_external_file(location) }
+            locations
+              .compact
+              .map(&method(:normalize_location))
+              .map(&method(:select_first_matching))
           end
 
           private
 
-          attr_reader :locations, :project, :sha
+          attr_reader :locations, :project, :sha, :user
+
+          # convert location if String to canonical form
+          def normalize_location(location)
+            if location.is_a?(String)
+              normalize_location_string(location)
+            else
+              location.deep_symbolize_keys
+            end
+          end
 
-          def build_external_file(location)
+          def normalize_location_string(location)
             if ::Gitlab::UrlSanitizer.valid?(location)
-              External::File::Remote.new(location)
+              { remote: location }
             else
-              External::File::Local.new(location, project: project, sha: sha)
+              { local: location }
+            end
+          end
+
+          def select_first_matching(location)
+            matching = FILE_CLASSES.map do |file_class|
+              file_class.new(location, context)
+            end.select(&:matching?)
+
+            raise AmbigiousSpecificationError, "Include `#{location.to_json}` needs to match exactly one accessor!" unless matching.one?
+
+            matching.first
+          end
+
+          def context
+            strong_memoize(:context) do
+              External::File::Base::Context.new(project, sha)
             end
           end
         end

lib/gitlab/ci/config/external/processor.rb

@@ -7,10 +7,12 @@ module Gitlab
         class Processor
           IncludeError = Class.new(StandardError)
 
-          def initialize(values, project, sha)
+          def initialize(values, project:, sha:)
             @values = values
-            @external_files = External::Mapper.new(values, project, sha).process
+            @external_files = External::Mapper.new(values, project: project, sha: sha).process
             @content = {}
+          rescue External::Mapper::AmbigiousSpecificationError => e
+            raise IncludeError, e.message
           end
 
           def perform

spec/lib/gitlab/ci/config/external/file/base_spec.rb

@@ -3,13 +3,43 @@
 require 'fast_spec_helper'
 
 describe Gitlab::Ci::Config::External::File::Base do
-  subject { described_class.new(location) }
+  let(:context) { described_class::Context.new(nil, 'HEAD') }
+
+  let(:test_class) do
+    Class.new(described_class) do
+      def initialize(params, context = {})
+        @location = params
+
+        super
+      end
+    end
+  end
+
+  subject { test_class.new(location, context) }
 
   before do
-    allow_any_instance_of(described_class)
+    allow_any_instance_of(test_class)
       .to receive(:content).and_return('key: value')
   end
 
+  describe '#matching?' do
+    context 'when a location is present' do
+      let(:location) { 'some-location' }
+
+      it 'should return true' do
+        expect(subject).to be_matching
+      end
+    end
+
+    context 'with a location is missing' do
+      let(:location) { nil }
+
+      it 'should return false' do
+        expect(subject).not_to be_matching
+      end
+    end
+  end
+
   describe '#valid?' do
     context 'when location is not a YAML file' do
       let(:location) { 'some/file.txt' }
@@ -39,7 +69,7 @@ describe Gitlab::Ci::Config::External::File::Base do
       let(:location) { 'some/file/config.yml' }
 
       before do
-        allow_any_instance_of(described_class)
+        allow_any_instance_of(test_class)
           .to receive(:content).and_return('invalid_syntax')
       end
 

spec/lib/gitlab/ci/config/external/file/local_spec.rb

@@ -3,8 +3,37 @@
 require 'spec_helper'
 
 describe Gitlab::Ci::Config::External::File::Local do
-  let(:project) { create(:project, :repository) }
-  let(:local_file) { described_class.new(location, { project: project, sha: '12345' }) }
+  set(:project) { create(:project, :repository) }
+
+  let(:context) { described_class::Context.new(project, '12345') }
+  let(:params) { { local: location } }
+  let(:local_file) { described_class.new(params, context) }
+
+  describe '#matching?' do
+    context 'when a local is specified' do
+      let(:params) { { local: 'file' } }
+
+      it 'should return true' do
+        expect(local_file).to be_matching
+      end
+    end
+
+    context 'with a missing local' do
+      let(:params) { { local: nil } }
+
+      it 'should return false' do
+        expect(local_file).not_to be_matching
+      end
+    end
+
+    context 'with a missing local key' do
+      let(:params) { {} }
+
+      it 'should return false' do
+        expect(local_file).not_to be_matching
+      end
+    end
+  end
 
   describe '#valid?' do
     context 'when is a valid local path' do

spec/lib/gitlab/ci/config/external/file/remote_spec.rb

@@ -3,7 +3,9 @@
 require 'spec_helper'
 
 describe Gitlab::Ci::Config::External::File::Remote do
-  let(:remote_file) { described_class.new(location) }
+  let(:context) { described_class::Context.new(nil, '12345') }
+  let(:params) { { remote: location } }
+  let(:remote_file) { described_class.new(params, context) }
   let(:location) { 'https://gitlab.com/gitlab-org/gitlab-ce/blob/1234/.gitlab-ci-1.yml' }
   let(:remote_file_content) do
     <<~HEREDOC
@@ -15,6 +17,32 @@ describe Gitlab::Ci::Config::External::File::Remote do
     HEREDOC
   end
 
+  describe '#matching?' do
+    context 'when a remote is specified' do
+      let(:params) { { remote: 'http://remote' } }
+
+      it 'should return true' do
+        expect(remote_file).to be_matching
+      end
+    end
+
+    context 'with a missing remote' do
+      let(:params) { { remote: nil } }
+
+      it 'should return false' do
+        expect(remote_file).not_to be_matching
+      end
+    end
+
+    context 'with a missing remote key' do
+      let(:params) { {} }
+
+      it 'should return false' do
+        expect(remote_file).not_to be_matching
+      end
+    end
+  end
+
   describe "#valid?" do
     context 'when is a valid remote url' do
       before do

spec/lib/gitlab/ci/config/external/file/template_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Gitlab::Ci::Config::External::File::Template do
+  let(:context) { described_class::Context.new(nil, '12345') }
+  let(:template) { 'Auto-DevOps.gitlab-ci.yml' }
+  let(:params) { { template: template } }
+
+  subject { described_class.new(params, context) }
+
+  describe '#matching?' do
+    context 'when a template is specified' do
+      let(:params) { { template: 'some-template' } }
+
+      it 'should return true' do
+        expect(subject).to be_matching
+      end
+    end
+
+    context 'with a missing template' do
+      let(:params) { { template: nil } }
+
+      it 'should return false' do
+        expect(subject).not_to be_matching
+      end
+    end
+
+    context 'with a missing template key' do
+      let(:params) { {} }
+
+      it 'should return false' do
+        expect(subject).not_to be_matching
+      end
+    end
+  end
+
+  describe "#valid?" do
+    context 'when is a valid template name' do
+      let(:template) { 'Auto-DevOps.gitlab-ci.yml' }
+
+      it 'should return true' do
+        expect(subject).to be_valid
+      end
+    end
+
+    context 'with invalid template name' do
+      let(:template) { 'Template.yml' }
+
+      it 'should return false' do
+        expect(subject).not_to be_valid
+        expect(subject.error_message).to include('Template file `Template.yml` is not a valid location!')
+      end
+    end
+
+    context 'with a non-existing template' do
+      let(:template) { 'I-Do-Not-Have-This-Template.gitlab-ci.yml' }
+
+      it 'should return false' do
+        expect(subject).not_to be_valid
+        expect(subject.error_message).to include('Included file `I-Do-Not-Have-This-Template.gitlab-ci.yml` is empty or does not exist!')
+      end
+    end
+  end
+
+  describe '#template_name' do
+    let(:template_name) { subject.send(:template_name) }
+
+    context 'when template does end with .gitlab-ci.yml' do
+      let(:template) { 'my-template.gitlab-ci.yml' }
+
+      it 'returns template name' do
+        expect(template_name).to eq('my-template')
+      end
+    end
+
+    context 'when template is nil' do
+      let(:template) { nil }
+
+      it 'returns nil' do
+        expect(template_name).to be_nil
+      end
+    end
+
+    context 'when template does not end with .gitlab-ci.yml' do
+      let(:template) { 'my-template' }
+
+      it 'returns nil' do
+        expect(template_name).to be_nil
+      end
+    end
+  end
+end

spec/lib/gitlab/ci/config/external/mapper_spec.rb

@@ -3,84 +3,130 @@
 require 'spec_helper'
 
 describe Gitlab::Ci::Config::External::Mapper do
-  let(:project) { create(:project, :repository) }
+  set(:project) { create(:project, :repository) }
+
+  let(:local_file) { '/lib/gitlab/ci/templates/non-existent-file.yml' }
+  let(:remote_url) { 'https://gitlab.com/gitlab-org/gitlab-ce/blob/1234/.gitlab-ci-1.yml' }
+  let(:template_file) { 'Auto-DevOps.gitlab-ci.yml' }
+
   let(:file_content) do
     <<~HEREDOC
     image: 'ruby:2.2'
     HEREDOC
   end
 
+  before do
+    WebMock.stub_request(:get, remote_url).to_return(body: file_content)
+  end
+
   describe '#process' do
-    subject { described_class.new(values, project, '123456').process }
+    subject { described_class.new(values, project: project, sha: '123456').process }
 
-    context "when 'include' keyword is defined as string" do
+    context "when single 'include' keyword is defined" do
       context 'when the string is a local file' do
         let(:values) do
-          {
-            include: '/lib/gitlab/ci/templates/non-existent-file.yml',
-            image: 'ruby:2.2'
-          }
+          { include: local_file,
+            image: 'ruby:2.2' }
         end
 
-        it 'returns an array' do
-          expect(subject).to be_an(Array)
+        it 'returns File instances' do
+          expect(subject).to contain_exactly(
+            an_instance_of(Gitlab::Ci::Config::External::File::Local))
+        end
+      end
+
+      context 'when the key is a local file hash' do
+        let(:values) do
+          { include: { 'local' => local_file },
+            image: 'ruby:2.2' }
         end
 
         it 'returns File instances' do
-          expect(subject.first)
-            .to be_an_instance_of(Gitlab::Ci::Config::External::File::Local)
+          expect(subject).to contain_exactly(
+            an_instance_of(Gitlab::Ci::Config::External::File::Local))
         end
       end
 
       context 'when the string is a remote file' do
-        let(:remote_url) { 'https://gitlab.com/gitlab-org/gitlab-ce/blob/1234/.gitlab-ci-1.yml' }
         let(:values) do
-          {
-            include: remote_url,
-            image: 'ruby:2.2'
-          }
+          { include: remote_url, image: 'ruby:2.2' }
         end
 
-        before do
-          WebMock.stub_request(:get, remote_url).to_return(body: file_content)
+        it 'returns File instances' do
+          expect(subject).to contain_exactly(
+            an_instance_of(Gitlab::Ci::Config::External::File::Remote))
+        end
+      end
+
+      context 'when the key is a remote file hash' do
+        let(:values) do
+          { include: { 'remote' => remote_url },
+            image: 'ruby:2.2' }
+        end
+
+        it 'returns File instances' do
+          expect(subject).to contain_exactly(
+            an_instance_of(Gitlab::Ci::Config::External::File::Remote))
+        end
       end
 
-        it 'returns an array' do
-          expect(subject).to be_an(Array)
+      context 'when the key is a template file hash' do
+        let(:values) do
+          { include: { 'template' => template_file },
+            image: 'ruby:2.2' }
         end
 
         it 'returns File instances' do
-          expect(subject.first)
-            .to be_an_instance_of(Gitlab::Ci::Config::External::File::Remote)
+          expect(subject).to contain_exactly(
+            an_instance_of(Gitlab::Ci::Config::External::File::Template))
+        end
+      end
+
+      context 'when the key is a hash of file and remote' do
+        let(:values) do
+          { include: { 'local' => local_file, 'remote' => remote_url },
+            image: 'ruby:2.2' }
+        end
+
+        it 'returns ambigious specification error' do
+          expect { subject }.to raise_error(described_class::AmbigiousSpecificationError)
         end
       end
     end
 
     context "when 'include' is defined as an array" do
-      let(:remote_url) { 'https://gitlab.com/gitlab-org/gitlab-ce/blob/1234/.gitlab-ci-1.yml' }
       let(:values) do
-        {
-          include:
-          [
-            remote_url,
-            '/lib/gitlab/ci/templates/template.yml'
-          ],
-          image: 'ruby:2.2'
-        }
+        { include: [remote_url, local_file],
+          image: 'ruby:2.2' }
       end
 
-      before do
-        WebMock.stub_request(:get, remote_url).to_return(body: file_content)
+      it 'returns Files instances' do
+        expect(subject).to all(respond_to(:valid?))
+        expect(subject).to all(respond_to(:content))
+      end
     end
 
-      it 'returns an array' do
-        expect(subject).to be_an(Array)
+    context "when 'include' is defined as an array of hashes" do
+      let(:values) do
+        { include: [{ remote: remote_url }, { local: local_file }],
+          image: 'ruby:2.2' }
       end
 
       it 'returns Files instances' do
         expect(subject).to all(respond_to(:valid?))
         expect(subject).to all(respond_to(:content))
       end
+
+      context 'when it has ambigious match' do
+        let(:values) do
+          { include: [{ remote: remote_url, local: local_file }],
+            image: 'ruby:2.2' }
+        end
+
+        it 'returns ambigious specification error' do
+          expect { subject }.to raise_error(described_class::AmbigiousSpecificationError)
+        end
+      end
     end
 
     context "when 'include' is not defined" do

spec/lib/gitlab/ci/config/external/processor_spec.rb

@@ -3,8 +3,9 @@
 require 'spec_helper'
 
 describe Gitlab::Ci::Config::External::Processor do
-  let(:project) { create(:project, :repository) }
-  let(:processor) { described_class.new(values, project, '12345') }
+  set(:project) { create(:project, :repository) }
+
+  let(:processor) { described_class.new(values, project: project, sha: '12345') }
 
   describe "#perform" do
     context 'when no external files defined' do

spec/lib/gitlab/ci/config_spec.rb

@@ -205,6 +205,23 @@ describe Gitlab::Ci::Config do
       end
     end
 
+    context "when gitlab_ci.yml has ambigious 'include' defined"  do
+      let(:gitlab_ci_yml) do
+        <<~HEREDOC
+          include:
+            remote: http://url
+            local: /local/file.yml
+        HEREDOC
+      end
+
+      it 'raises error YamlProcessor validationError' do
+        expect { config }.to raise_error(
+          described_class::ConfigError,
+          'Include `{"remote":"http://url","local":"/local/file.yml"}` needs to match exactly one accessor!'
+        )
+      end
+    end
+
     describe 'external file version' do
       context 'when external local file SHA is defined' do
         it 'is using a defined value' do