Move create service to snippets namespace

- Renamed CreateSnippetService into Snippets::CreateService
- Return a ServiceResponse from the CreateService
- Refactor Snippets::CreateService spec

app/controllers/projects/snippets_controller.rb

@@ -46,8 +46,8 @@ class Projects::SnippetsController < Projects::ApplicationController
 
   def create
     create_params = snippet_params.merge(spammable_params)
-
-    @snippet = CreateSnippetService.new(@project, current_user, create_params).execute
+    service_response = Snippets::CreateService.new(project, current_user, create_params).execute
+    @snippet = service_response.payload[:snippet]
 
     recaptcha_check_with_fallback { render :new }
   end
@@ -55,7 +55,8 @@ class Projects::SnippetsController < Projects::ApplicationController
   def update
     update_params = snippet_params.merge(spammable_params)
 
-    UpdateSnippetService.new(project, current_user, @snippet, update_params).execute
+    service_response = Snippets::UpdateService.new(project, current_user, update_params).execute(@snippet)
+    @snippet = service_response.payload[:snippet]
 
     recaptcha_check_with_fallback { render :edit }
   end
@@ -89,11 +90,17 @@ class Projects::SnippetsController < Projects::ApplicationController
   end
 
   def destroy
-    return access_denied! unless can?(current_user, :admin_project_snippet, @snippet)
-
-    @snippet.destroy
-
-    redirect_to project_snippets_path(@project), status: :found
+    service_response = Snippets::DestroyService.new(current_user, @snippet).execute
+
+    if service_response.success?
+      redirect_to project_snippets_path(project), status: :found
+    elsif service_response.http_status == 403
+      access_denied!
+    else
+      redirect_to project_snippet_path(project, @snippet),
+                  status: :found,
+                  alert: service_response.message
+    end
   end
 
   protected

app/controllers/snippets_controller.rb

@@ -50,8 +50,8 @@ class SnippetsController < ApplicationController
 
   def create
     create_params = snippet_params.merge(spammable_params)
-
-    @snippet = CreateSnippetService.new(nil, current_user, create_params).execute
+    service_response = Snippets::CreateService.new(nil, current_user, create_params).execute
+    @snippet = service_response.payload[:snippet]
 
     move_temporary_files if @snippet.valid? && params[:files]
 
@@ -61,7 +61,8 @@ class SnippetsController < ApplicationController
   def update
     update_params = snippet_params.merge(spammable_params)
 
-    UpdateSnippetService.new(nil, current_user, @snippet, update_params).execute
+    service_response = Snippets::UpdateService.new(nil, current_user, update_params).execute(@snippet)
+    @snippet = service_response.payload[:snippet]
 
     recaptcha_check_with_fallback { render :edit }
   end
@@ -96,11 +97,17 @@ class SnippetsController < ApplicationController
   end
 
   def destroy
-    return access_denied! unless can?(current_user, :admin_personal_snippet, @snippet)
-
-    @snippet.destroy
+    service_response = Snippets::DestroyService.new(current_user, @snippet).execute
 
-    redirect_to snippets_path, status: :found
+    if service_response.success?
+      redirect_to dashboard_snippets_path, status: :found
+    elsif service_response.http_status == 403
+      access_denied!
+    else
+      redirect_to snippet_path(@snippet),
+                  status: :found,
+                  alert: service_response.message
+    end
   end
 
   protected

app/graphql/mutations/snippets/create.rb

@@ -45,9 +45,10 @@ module Mutations
           raise_resource_not_available_error!
         end
 
-        snippet = CreateSnippetService.new(project,
+        service_response = ::Snippets::CreateService.new(project,
                                            context[:current_user],
                                            args).execute
+        snippet = service_response.payload[:snippet]
 
         {
           snippet: snippet.valid? ? snippet : nil,

app/graphql/mutations/snippets/destroy.rb

@@ -15,8 +15,8 @@ module Mutations
       def resolve(id:)
         snippet = authorized_find!(id: id)
 
-        result = snippet.destroy
-        errors = result ? [] : [ERROR_MSG]
+        response = ::Snippets::DestroyService.new(current_user, snippet).execute
+        errors = response.success? ? [] : [ERROR_MSG]
 
         {
           errors: errors

app/graphql/mutations/snippets/update.rb

@@ -33,13 +33,13 @@ module Mutations
       def resolve(args)
         snippet = authorized_find!(id: args.delete(:id))
 
-        result = UpdateSnippetService.new(snippet.project,
+        result = ::Snippets::UpdateService.new(snippet.project,
                                           context[:current_user],
-                                          snippet,
-                                          args).execute
+                                          args).execute(snippet)
+        snippet = result.payload[:snippet]
 
         {
-          snippet: result ? snippet : snippet.reset,
+          snippet: result.success? ? snippet : snippet.reset,
           errors: errors_on_object(snippet)
         }
       end

app/services/create_snippet_service.rb

-# frozen_string_literal: true
-
-class CreateSnippetService < BaseService
-  include SpamCheckMethods
-
-  def execute
-    filter_spam_check_params
-
-    snippet = if project
-                project.snippets.build(params)
-              else
-                PersonalSnippet.new(params)
-              end
-
-    unless Gitlab::VisibilityLevel.allowed_for?(current_user, snippet.visibility_level)
-      deny_visibility_level(snippet)
-      return snippet
-    end
-
-    snippet.author = current_user
-
-    spam_check(snippet, current_user)
-
-    snippet_saved = snippet.with_transaction_returning_status do
-      snippet.save && snippet.store_mentions!
-    end
-
-    if snippet_saved
-      UserAgentDetailService.new(snippet, @request).create
-      Gitlab::UsageDataCounters::SnippetCounter.count(:create)
-    end
-
-    snippet
-  end
-end

app/services/snippets/base_service.rb

+# frozen_string_literal: true
+
+module Snippets
+  class BaseService < ::BaseService
+    private
+
+    def snippet_error_response(snippet, http_status)
+      ServiceResponse.error(
+        message: snippet.errors.full_messages.to_sentence,
+        http_status: http_status,
+        payload: { snippet: snippet }
+      )
+    end
+  end
+end

app/services/snippets/create_service.rb

+# frozen_string_literal: true
+
+module Snippets
+  class CreateService < Snippets::BaseService
+    include SpamCheckMethods
+
+    def execute
+      filter_spam_check_params
+
+      snippet = if project
+                  project.snippets.build(params)
+                else
+                  PersonalSnippet.new(params)
+                end
+
+      unless Gitlab::VisibilityLevel.allowed_for?(current_user, snippet.visibility_level)
+        deny_visibility_level(snippet)
+
+        return snippet_error_response(snippet, 403)
+      end
+
+      snippet.author = current_user
+
+      spam_check(snippet, current_user)
+
+      snippet_saved = snippet.with_transaction_returning_status do
+        snippet.save && snippet.store_mentions!
+      end
+
+      if snippet_saved
+        UserAgentDetailService.new(snippet, @request).create
+        Gitlab::UsageDataCounters::SnippetCounter.count(:create)
+
+        ServiceResponse.success(payload: { snippet: snippet } )
+      else
+        snippet_error_response(snippet, 400)
+      end
+    end
+  end
+end

app/services/snippets/destroy_service.rb

+# frozen_string_literal: true
+
+module Snippets
+  class DestroyService
+    include Gitlab::Allowable
+
+    attr_reader :current_user, :project
+
+    def initialize(user, snippet)
+      @current_user = user
+      @snippet = snippet
+      @project = snippet&.project
+    end
+
+    def execute
+      if snippet.nil?
+        return service_response_error('No snippet found.', 404)
+      end
+
+      unless user_can_delete_snippet?
+        return service_response_error(
+          "You don't have access to delete this snippet.",
+          403
+        )
+      end
+
+      if snippet.destroy
+        ServiceResponse.success(message: 'Snippet was deleted.')
+      else
+        service_response_error('Failed to remove snippet.', 400)
+      end
+    end
+
+    private
+
+    attr_reader :snippet
+
+    def user_can_delete_snippet?
+      return can?(current_user, :admin_project_snippet, snippet) if project
+
+      can?(current_user, :admin_personal_snippet, snippet)
+    end
+
+    def service_response_error(message, http_status)
+      ServiceResponse.error(message: message, http_status: http_status)
+    end
+  end
+end

app/services/snippets/update_service.rb

+# frozen_string_literal: true
+
+module Snippets
+  class UpdateService < Snippets::BaseService
+    include SpamCheckMethods
+
+    def execute(snippet)
+      # check that user is allowed to set specified visibility_level
+      new_visibility = visibility_level
+
+      if new_visibility && new_visibility.to_i != snippet.visibility_level
+        unless Gitlab::VisibilityLevel.allowed_for?(current_user, new_visibility)
+          deny_visibility_level(snippet, new_visibility)
+
+          return snippet_error_response(snippet, 403)
+        end
+      end
+
+      filter_spam_check_params
+      snippet.assign_attributes(params)
+      spam_check(snippet, current_user)
+
+      snippet_saved = snippet.with_transaction_returning_status do
+        snippet.save && snippet.store_mentions!
+      end
+
+      if snippet_saved
+        Gitlab::UsageDataCounters::SnippetCounter.count(:update)
+
+        ServiceResponse.success(payload: { snippet: snippet } )
+      else
+        snippet_error_response(snippet, 400)
+      end
+    end
+  end
+end

app/services/update_snippet_service.rb

-# frozen_string_literal: true
-
-class UpdateSnippetService < BaseService
-  include SpamCheckMethods
-
-  attr_accessor :snippet
-
-  def initialize(project, user, snippet, params)
-    super(project, user, params)
-    @snippet = snippet
-  end
-
-  def execute
-    # check that user is allowed to set specified visibility_level
-    new_visibility = visibility_level
-
-    if new_visibility && new_visibility.to_i != snippet.visibility_level
-      unless Gitlab::VisibilityLevel.allowed_for?(current_user, new_visibility)
-        deny_visibility_level(snippet, new_visibility)
-        return snippet
-      end
-    end
-
-    filter_spam_check_params
-    snippet.assign_attributes(params)
-    spam_check(snippet, current_user)
-
-    snippet_saved = snippet.with_transaction_returning_status do
-      snippet.save && snippet.store_mentions!
-    end
-
-    if snippet_saved
-      Gitlab::UsageDataCounters::SnippetCounter.count(:update)
-    end
-  end
-end

lib/api/project_snippets.rb

@@ -64,7 +64,8 @@ module API
         snippet_params = declared_params(include_missing: false).merge(request: request, api: true)
         snippet_params[:content] = snippet_params.delete(:code) if snippet_params[:code].present?
 
-        snippet = CreateSnippetService.new(user_project, current_user, snippet_params).execute
+        service_response = ::Snippets::CreateService.new(user_project, current_user, snippet_params).execute
+        snippet = service_response.payload[:snippet]
 
         render_spam_error! if snippet.spam?
 
@@ -103,8 +104,8 @@ module API
 
         snippet_params[:content] = snippet_params.delete(:code) if snippet_params[:code].present?
 
-        UpdateSnippetService.new(user_project, current_user, snippet,
-                                 snippet_params).execute
+        service_response = ::Snippets::UpdateService.new(user_project, current_user, snippet_params).execute(snippet)
+        snippet = service_response.payload[:snippet]
 
         render_spam_error! if snippet.spam?
 
@@ -127,7 +128,14 @@ module API
 
         authorize! :admin_project_snippet, snippet
 
-        destroy_conditionally!(snippet)
+        destroy_conditionally!(snippet) do |snippet|
+          service = ::Snippets::DestroyService.new(current_user, snippet)
+          response = service.execute
+
+          if response.error?
+            render_api_error!({ error: response.message }, response.http_status)
+          end
+        end
       end
       # rubocop: enable CodeReuse/ActiveRecord
 

lib/api/snippets.rb

@@ -75,7 +75,8 @@ module API
       end
       post do
         attrs = declared_params(include_missing: false).merge(request: request, api: true)
-        snippet = CreateSnippetService.new(nil, current_user, attrs).execute
+        service_response = ::Snippets::CreateService.new(nil, current_user, attrs).execute
+        snippet = service_response.payload[:snippet]
 
         render_spam_error! if snippet.spam?
 
@@ -108,8 +109,8 @@ module API
         authorize! :update_personal_snippet, snippet
 
         attrs = declared_params(include_missing: false).merge(request: request, api: true)
-
-        UpdateSnippetService.new(nil, current_user, snippet, attrs).execute
+        service_response = ::Snippets::UpdateService.new(nil, current_user, attrs).execute(snippet)
+        snippet = service_response.payload[:snippet]
 
         render_spam_error! if snippet.spam?
 
@@ -133,7 +134,14 @@ module API
 
         authorize! :admin_personal_snippet, snippet
 
-        destroy_conditionally!(snippet)
+        destroy_conditionally!(snippet) do |snippet|
+          service = ::Snippets::DestroyService.new(current_user, snippet)
+          response = service.execute
+
+          if response.error?
+            render_api_error!({ error: response.message }, response.http_status)
+          end
+        end
       end
 
       desc 'Get a raw snippet' do

spec/controllers/projects/snippets_controller_spec.rb

@@ -445,4 +445,64 @@ describe Projects::SnippetsController do
       end
     end
   end
+
+  describe 'DELETE #destroy' do
+    let!(:snippet) { create(:project_snippet, :private, project: project, author: user) }
+
+    let(:params) do
+      {
+        namespace_id: project.namespace.to_param,
+        project_id: project,
+        id: snippet.to_param
+      }
+    end
+
+    context 'when current user has ability to destroy the snippet' do
+      before do
+        sign_in(user)
+      end
+
+      it 'removes the snippet' do
+        delete :destroy, params: params
+
+        expect { snippet.reload }.to raise_error(ActiveRecord::RecordNotFound)
+      end
+
+      context 'when snippet is succesfuly destroyed' do
+        it 'redirects to the project snippets page' do
+          delete :destroy, params: params
+
+          expect(response).to redirect_to(project_snippets_path(project))
+        end
+      end
+
+      context 'when snippet is not destroyed' do
+        before do
+          allow(snippet).to receive(:destroy).and_return(false)
+          controller.instance_variable_set(:@snippet, snippet)
+        end
+
+        it 'renders the snippet page with errors' do
+          delete :destroy, params: params
+
+          expect(flash[:alert]).to eq('Failed to remove snippet.')
+          expect(response).to redirect_to(project_snippet_path(project, snippet))
+        end
+      end
+    end
+
+    context 'when current_user does not have ability to destroy the snippet' do
+      let(:another_user) { create(:user) }
+
+      before do
+        sign_in(another_user)
+      end
+
+      it 'responds with status 404' do
+        delete :destroy, params: params
+
+        expect(response).to have_gitlab_http_status(404)
+      end
+    end
+  end
 end

spec/controllers/snippets_controller_spec.rb

@@ -664,4 +664,56 @@ describe SnippetsController do
       expect(json_response.keys).to match_array(%w(body references))
     end
   end
+
+  describe 'DELETE #destroy' do
+    let!(:snippet) { create :personal_snippet, author: user }
+
+    context 'when current user has ability to destroy the snippet' do
+      before do
+        sign_in(user)
+      end
+
+      it 'removes the snippet' do
+        delete :destroy, params: { id: snippet.to_param }
+
+        expect { snippet.reload }.to raise_error(ActiveRecord::RecordNotFound)
+      end
+
+      context 'when snippet is succesfuly destroyed' do
+        it 'redirects to the project snippets page' do
+          delete :destroy, params: { id: snippet.to_param }
+
+          expect(response).to redirect_to(dashboard_snippets_path)
+        end
+      end
+
+      context 'when snippet is not destroyed' do
+        before do
+          allow(snippet).to receive(:destroy).and_return(false)
+          controller.instance_variable_set(:@snippet, snippet)
+        end
+
+        it 'renders the snippet page with errors' do
+          delete :destroy, params: { id: snippet.to_param }
+
+          expect(flash[:alert]).to eq('Failed to remove snippet.')
+          expect(response).to redirect_to(snippet_path(snippet))
+        end
+      end
+    end
+
+    context 'when current_user does not have ability to destroy the snippet' do
+      let(:another_user) { create(:user) }
+
+      before do
+        sign_in(another_user)
+      end
+
+      it 'responds with status 404' do
+        delete :destroy, params: { id: snippet.to_param }
+
+        expect(response).to have_gitlab_http_status(404)
+      end
+    end
+  end
 end

spec/services/create_snippet_service_spec.rb

-# frozen_string_literal: true
-
-require 'spec_helper'
-
-describe CreateSnippetService do
-  let(:user) { create(:user) }
-  let(:admin) { create(:user, :admin) }
-  let(:opts) { base_opts.merge(extra_opts) }
-  let(:base_opts) do
-    {
-      title: 'Test snippet',
-      file_name: 'snippet.rb',
-      content: 'puts "hello world"',
-      visibility_level: Gitlab::VisibilityLevel::PRIVATE
-    }
-  end
-  let(:extra_opts) { {} }
-
-  context 'When public visibility is restricted' do
-    let(:extra_opts) { { visibility_level: Gitlab::VisibilityLevel::PUBLIC } }
-
-    before do
-      stub_application_setting(restricted_visibility_levels: [Gitlab::VisibilityLevel::PUBLIC])
-    end
-
-    it 'non-admins are not able to create a public snippet' do
-      snippet = create_snippet(nil, user, opts)
-      expect(snippet.errors.messages).to have_key(:visibility_level)
-      expect(snippet.errors.messages[:visibility_level].first).to(
-        match('has been restricted')
-      )
-    end
-
-    it 'admins are able to create a public snippet' do
-      snippet = create_snippet(nil, admin, opts)
-      expect(snippet.errors.any?).to be_falsey
-      expect(snippet.visibility_level).to eq(Gitlab::VisibilityLevel::PUBLIC)
-    end
-
-    describe "when visibility level is passed as a string" do
-      let(:extra_opts) { { visibility: 'internal' } }
-
-      before do
-        base_opts.delete(:visibility_level)
-      end
-
-      it "assigns the correct visibility level" do
-        snippet = create_snippet(nil, user, opts)
-        expect(snippet.errors.any?).to be_falsey
-        expect(snippet.visibility_level).to eq(Gitlab::VisibilityLevel::INTERNAL)
-      end
-    end
-  end
-
-  context 'checking spam' do
-    shared_examples 'marked as spam' do
-      let(:snippet) { create_snippet(nil, admin, opts) }
-
-      it 'marks a snippet as a spam ' do
-        expect(snippet).to be_spam
-      end
-
-      it 'invalidates the snippet' do
-        expect(snippet).to be_invalid
-      end
-
-      it 'creates a new spam_log' do
-        expect { snippet }
-          .to log_spam(title: snippet.title, noteable_type: 'PersonalSnippet')
-      end
-
-      it 'assigns a spam_log to an issue' do
-        expect(snippet.spam_log).to eq(SpamLog.last)
-      end
-    end
-
-    let(:extra_opts) do
-      { visibility_level: Gitlab::VisibilityLevel::PUBLIC, request: double(:request, env: {}) }
-    end
-
-    before do
-      expect_next_instance_of(AkismetService) do |akismet_service|
-        expect(akismet_service).to receive_messages(spam?: true)
-      end
-    end
-
-    [true, false, nil].each do |allow_possible_spam|
-      context "when recaptcha_disabled flag is #{allow_possible_spam.inspect}" do
-        before do
-          stub_feature_flags(allow_possible_spam: allow_possible_spam) unless allow_possible_spam.nil?
-        end
-
-        it_behaves_like 'marked as spam'
-      end
-    end
-  end
-
-  describe 'usage counter' do
-    let(:counter) { Gitlab::UsageDataCounters::SnippetCounter }
-
-    it 'increments count' do
-      expect do
-        create_snippet(nil, admin, opts)
-      end.to change { counter.read(:create) }.by 1
-    end
-
-    it 'does not increment count if create fails' do
-      expect do
-        create_snippet(nil, admin, {})
-      end.not_to change { counter.read(:create) }
-    end
-  end
-
-  def create_snippet(project, user, opts)
-    CreateSnippetService.new(project, user, opts).execute
-  end
-end

spec/services/snippets/create_service_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Snippets::CreateService do
+  describe '#execute' do
+    let_it_be(:user) { create(:user) }
+    let_it_be(:admin) { create(:user, :admin) }
+    let(:opts) { base_opts.merge(extra_opts) }
+    let(:base_opts) do
+      {
+        title: 'Test snippet',
+        file_name: 'snippet.rb',
+        content: 'puts "hello world"',
+        visibility_level: Gitlab::VisibilityLevel::PRIVATE
+      }
+    end
+    let(:extra_opts) { {} }
+    let(:creator) { admin }
+
+    subject { Snippets::CreateService.new(project, creator, opts).execute }
+
+    let(:snippet) { subject.payload[:snippet] }
+
+    shared_examples 'a service that creates a snippet' do
+      it 'creates a snippet with the provided attributes' do
+        expect(snippet.title).to eq(opts[:title])
+        expect(snippet.file_name).to eq(opts[:file_name])
+        expect(snippet.content).to eq(opts[:content])
+        expect(snippet.visibility_level).to eq(opts[:visibility_level])
+      end
+    end
+
+    shared_examples 'public visibility level restrictions apply' do
+      let(:extra_opts) { { visibility_level: Gitlab::VisibilityLevel::PUBLIC } }
+
+      before do
+        stub_application_setting(restricted_visibility_levels: [Gitlab::VisibilityLevel::PUBLIC])
+      end
+
+      context 'when user is not an admin' do
+        let(:creator) { user }
+
+        it 'responds with an error' do
+          expect(subject).to be_error
+        end
+
+        it 'does not create a public snippet' do
+          expect(subject.message).to match('has been restricted')
+        end
+      end
+
+      context 'when user is an admin' do
+        it 'responds with success' do
+          expect(subject).to be_success
+        end
+
+        it 'creates a public snippet' do
+          expect(snippet.visibility_level).to eq(Gitlab::VisibilityLevel::PUBLIC)
+        end
+      end
+
+      describe 'when visibility level is passed as a string' do
+        let(:extra_opts) { { visibility: 'internal' } }
+
+        before do
+          base_opts.delete(:visibility_level)
+        end
+
+        it 'assigns the correct visibility level' do
+          expect(subject).to be_success
+          expect(snippet.visibility_level).to eq(Gitlab::VisibilityLevel::INTERNAL)
+        end
+      end
+    end
+
+    shared_examples 'spam check is performed' do
+      shared_examples 'marked as spam' do
+        it 'marks a snippet as spam ' do
+          expect(snippet).to be_spam
+        end
+
+        it 'invalidates the snippet' do
+          expect(snippet).to be_invalid
+        end
+
+        it 'creates a new spam_log' do
+          expect { snippet }
+            .to log_spam(title: snippet.title, noteable_type: snippet.class.name)
+        end
+
+        it 'assigns a spam_log to an issue' do
+          expect(snippet.spam_log).to eq(SpamLog.last)
+        end
+      end
+
+      let(:extra_opts) do
+        { visibility_level: Gitlab::VisibilityLevel::PUBLIC, request: double(:request, env: {}) }
+      end
+
+      before do
+        expect_next_instance_of(AkismetService) do |akismet_service|
+          expect(akismet_service).to receive_messages(spam?: true)
+        end
+      end
+
+      [true, false, nil].each do |allow_possible_spam|
+        context "when recaptcha_disabled flag is #{allow_possible_spam.inspect}" do
+          before do
+            stub_feature_flags(allow_possible_spam: allow_possible_spam) unless allow_possible_spam.nil?
+          end
+
+          it_behaves_like 'marked as spam'
+        end
+      end
+    end
+
+    shared_examples 'snippet create data is tracked' do
+      let(:counter) { Gitlab::UsageDataCounters::SnippetCounter }
+
+      it 'increments count when create succeeds' do
+        expect { subject }.to change { counter.read(:create) }.by 1
+      end
+
+      context 'when create fails' do
+        let(:opts) { {} }
+
+        it 'does not increment count' do
+          expect { subject }.not_to change { counter.read(:create) }
+        end
+      end
+    end
+
+    shared_examples 'an error service response when save fails' do
+      let(:extra_opts) { { content: nil } }
+
+      it 'responds with an error' do
+        expect(subject).to be_error
+      end
+
+      it 'does not create the snippet' do
+        expect { subject }.not_to change { Snippet.count }
+      end
+    end
+
+    context 'when Project Snippet' do
+      let_it_be(:project) { create(:project) }
+
+      before do
+        project.add_developer(user)
+      end
+
+      it_behaves_like 'a service that creates a snippet'
+      it_behaves_like 'public visibility level restrictions apply'
+      it_behaves_like 'spam check is performed'
+      it_behaves_like 'snippet create data is tracked'
+      it_behaves_like 'an error service response when save fails'
+    end
+
+    context 'when PersonalSnippet' do
+      let(:project) { nil }
+
+      it_behaves_like 'a service that creates a snippet'
+      it_behaves_like 'public visibility level restrictions apply'
+      it_behaves_like 'spam check is performed'
+      it_behaves_like 'snippet create data is tracked'
+      it_behaves_like 'an error service response when save fails'
+    end
+  end
+end

spec/services/snippets/destroy_service_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Snippets::DestroyService do
+  let_it_be(:project) { create(:project) }
+  let_it_be(:user) { create(:user) }
+  let_it_be(:other_user) { create(:user) }
+
+  describe '#execute' do
+    subject { Snippets::DestroyService.new(user, snippet).execute }
+
+    context 'when snippet is nil' do
+      let(:snippet) { nil }
+
+      it 'returns a ServiceResponse error' do
+        expect(subject).to be_error
+      end
+    end
+
+    shared_examples 'a successful destroy' do
+      it 'deletes the snippet' do
+        expect { subject }.to change { Snippet.count }.by(-1)
+      end
+
+      it 'returns ServiceResponse success' do
+        expect(subject).to be_success
+      end
+    end
+
+    shared_examples 'an unsuccessful destroy' do
+      it 'does not delete the snippet' do
+        expect { subject }.to change { Snippet.count }.by(0)
+      end
+
+      it 'returns ServiceResponse error' do
+        expect(subject).to be_error
+      end
+    end
+
+    context 'when ProjectSnippet' do
+      let!(:snippet) { create(:project_snippet, project: project, author: author) }
+
+      context 'when user is able to admin_project_snippet' do
+        let(:author) { user }
+
+        before do
+          project.add_developer(user)
+        end
+
+        it_behaves_like 'a successful destroy'
+      end
+
+      context 'when user is not able to admin_project_snippet' do
+        let(:author) { other_user }
+
+        it_behaves_like 'an unsuccessful destroy'
+      end
+    end
+
+    context 'when PersonalSnippet' do
+      let!(:snippet) { create(:personal_snippet, author: author) }
+
+      context 'when user is able to admin_personal_snippet' do
+        let(:author) { user }
+
+        it_behaves_like 'a successful destroy'
+      end
+
+      context 'when user is not able to admin_personal_snippet' do
+        let(:author) { other_user }
+
+        it_behaves_like 'an unsuccessful destroy'
+      end
+    end
+  end
+end

spec/services/snippets/update_service_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Snippets::UpdateService do
+  describe '#execute' do
+    let_it_be(:user) { create(:user) }
+    let_it_be(:admin) { create :user, admin: true }
+    let(:visibility_level) { Gitlab::VisibilityLevel::PRIVATE }
+    let(:options) do
+      {
+        title: 'Test snippet',
+        file_name: 'snippet.rb',
+        content: 'puts "hello world"',
+        visibility_level: visibility_level
+      }
+    end
+    let(:updater) { user }
+
+    subject do
+      Snippets::UpdateService.new(
+        project,
+        updater,
+        options
+      ).execute(snippet)
+    end
+
+    shared_examples 'a service that updates a snippet' do
+      it 'updates a snippet with the provided attributes' do
+        expect { subject }.to change { snippet.title }.from(snippet.title).to(options[:title])
+          .and change { snippet.file_name }.from(snippet.file_name).to(options[:file_name])
+          .and change { snippet.content }.from(snippet.content).to(options[:content])
+      end
+    end
+
+    shared_examples 'public visibility level restrictions apply' do
+      let(:visibility_level) { Gitlab::VisibilityLevel::PUBLIC }
+
+      before do
+        stub_application_setting(restricted_visibility_levels: [Gitlab::VisibilityLevel::PUBLIC])
+      end
+
+      context 'when user is not an admin' do
+        it 'responds with an error' do
+          expect(subject).to be_error
+        end
+
+        it 'does not update snippet to public visibility' do
+          original_visibility = snippet.visibility_level
+
+          expect(subject.message).to match('has been restricted')
+          expect(snippet.visibility_level).to eq(original_visibility)
+        end
+      end
+
+      context 'when user is an admin' do
+        let(:updater) { admin }
+
+        it 'responds with success' do
+          expect(subject).to be_success
+        end
+
+        it 'updates the snippet to public visibility' do
+          old_visibility = snippet.visibility_level
+
+          expect(subject.payload[:snippet]).not_to be_nil
+          expect(snippet.visibility_level).not_to eq(old_visibility)
+          expect(snippet.visibility_level).to eq(Gitlab::VisibilityLevel::PUBLIC)
+        end
+      end
+
+      context 'when visibility level is passed as a string' do
+        before do
+          options[:visibility] = 'internal'
+          options.delete(:visibility_level)
+        end
+
+        it 'assigns the correct visibility level' do
+          expect(subject).to be_success
+          expect(snippet.visibility_level).to eq(Gitlab::VisibilityLevel::INTERNAL)
+        end
+      end
+    end
+
+    shared_examples 'snippet update data is tracked' do
+      let(:counter) { Gitlab::UsageDataCounters::SnippetCounter }
+
+      it 'increments count when create succeeds' do
+        expect { subject }.to change { counter.read(:update) }.by 1
+      end
+
+      context 'when update fails' do
+        let(:options) { { title: '' } }
+
+        it 'does not increment count' do
+          expect { subject }.not_to change { counter.read(:update) }
+        end
+      end
+    end
+
+    context 'when Project Snippet' do
+      let_it_be(:project) { create(:project) }
+      let!(:snippet) { create(:project_snippet, author: user, project: project) }
+
+      before do
+        project.add_developer(user)
+      end
+
+      it_behaves_like 'a service that updates a snippet'
+      it_behaves_like 'public visibility level restrictions apply'
+      it_behaves_like 'snippet update data is tracked'
+    end
+
+    context 'when PersonalSnippet' do
+      let(:project) { nil }
+      let!(:snippet) { create(:personal_snippet, author: user) }
+
+      it_behaves_like 'a service that updates a snippet'
+      it_behaves_like 'public visibility level restrictions apply'
+      it_behaves_like 'snippet update data is tracked'
+    end
+  end
+end

spec/services/update_snippet_service_spec.rb

-# frozen_string_literal: true
-
-require 'spec_helper'
-
-describe UpdateSnippetService do
-  before do
-    @user = create :user
-    @admin = create :user, admin: true
-    @opts = {
-      title: 'Test snippet',
-      file_name: 'snippet.rb',
-      content: 'puts "hello world"',
-      visibility_level: Gitlab::VisibilityLevel::PRIVATE
-    }
-  end
-
-  context 'When public visibility is restricted' do
-    before do
-      stub_application_setting(restricted_visibility_levels: [Gitlab::VisibilityLevel::PUBLIC])
-
-      @snippet = create_snippet(@project, @user, @opts)
-      @opts.merge!(visibility_level: Gitlab::VisibilityLevel::PUBLIC)
-    end
-
-    it 'non-admins should not be able to update to public visibility' do
-      old_visibility = @snippet.visibility_level
-      update_snippet(@project, @user, @snippet, @opts)
-      expect(@snippet.errors.messages).to have_key(:visibility_level)
-      expect(@snippet.errors.messages[:visibility_level].first).to(
-        match('has been restricted')
-      )
-      expect(@snippet.visibility_level).to eq(old_visibility)
-    end
-
-    it 'admins should be able to update to public visibility' do
-      old_visibility = @snippet.visibility_level
-      update_snippet(@project, @admin, @snippet, @opts)
-      expect(@snippet.visibility_level).not_to eq(old_visibility)
-      expect(@snippet.visibility_level).to eq(Gitlab::VisibilityLevel::PUBLIC)
-    end
-
-    describe "when visibility level is passed as a string" do
-      before do
-        @opts[:visibility] = 'internal'
-        @opts.delete(:visibility_level)
-      end
-
-      it "assigns the correct visibility level" do
-        update_snippet(@project, @user, @snippet, @opts)
-        expect(@snippet.errors.any?).to be_falsey
-        expect(@snippet.visibility_level).to eq(Gitlab::VisibilityLevel::INTERNAL)
-      end
-    end
-  end
-
-  describe 'usage counter' do
-    let(:counter) { Gitlab::UsageDataCounters::SnippetCounter }
-    let(:snippet) { create_snippet(nil, @user, @opts) }
-
-    it 'increments count' do
-      expect do
-        update_snippet(nil, @admin, snippet, @opts)
-      end.to change { counter.read(:update) }.by 1
-    end
-
-    it 'does not increment count if create fails' do
-      expect do
-        update_snippet(nil, @admin, snippet, { title: '' })
-      end.not_to change { counter.read(:update) }
-    end
-  end
-
-  def create_snippet(project, user, opts)
-    CreateSnippetService.new(project, user, opts).execute
-  end
-
-  def update_snippet(project, user, snippet, opts)
-    UpdateSnippetService.new(project, user, snippet, opts).execute
-  end
-end