Initial setup GraphQL using graphql-ruby 1.8

- All definitions have been replaced by classes:
  http://graphql-ruby.org/schema/class_based_api.html
- Authorization & Presentation have been refactored to work in the
  class based system
- Loaders have been replaced by resolvers
- Times are now coersed as ISO 8601

14 files changed, 208 insertions, 95 deletions

diff --git a/spec/graphql/gitlab_schema_spec.rb b/spec/graphql/gitlab_schema_spec.rb
index f25cc2fd6c9..b892f6b44ed 100644
--- a/spec/graphql/gitlab_schema_spec.rb
+++ b/spec/graphql/gitlab_schema_spec.rb
@@ -6,26 +6,25 @@ describe GitlabSchema do
   end
 
   it 'enables the preload instrumenter' do
-    expect(field_instrumenters).to include(instance_of(::GraphQL::Preload::Instrument))
+    expect(field_instrumenters).to include(BatchLoader::GraphQL)
   end
 
   it 'enables the authorization instrumenter' do
-    expect(field_instrumenters).to include(instance_of(::Gitlab::Graphql::Authorize))
+    expect(field_instrumenters).to include(instance_of(::Gitlab::Graphql::Authorize::Instrumentation))
   end
 
   it 'enables using presenters' do
-    expect(field_instrumenters).to include(instance_of(::Gitlab::Graphql::Present))
+    expect(field_instrumenters).to include(instance_of(::Gitlab::Graphql::Present::Instrumentation))
   end
 
   it 'has the base mutation' do
-    pending <<~REASON
-      Having empty mutations breaks the automatic documentation in Graphiql, so removed for now."
-    REASON
-    expect(described_class.mutation).to eq(::Types::MutationType)
+    pending('Adding an empty mutation breaks the documentation explorer')
+
+    expect(described_class.mutation).to eq(::Types::MutationType.to_graphql)
   end
 
   it 'has the base query' do
-    expect(described_class.query).to eq(::Types::QueryType)
+    expect(described_class.query).to eq(::Types::QueryType.to_graphql)
   end
 
   def field_instrumenters
diff --git a/spec/graphql/loaders/iid_loader_spec.rb b/spec/graphql/resolvers/merge_request_resolver_spec.rb
index 0a57d7c4ed4..af015533209 100644
--- a/spec/graphql/loaders/iid_loader_spec.rb
+++ b/spec/graphql/resolvers/merge_request_resolver_spec.rb
@@ -1,6 +1,6 @@
 require 'spec_helper'
 
-describe Loaders::IidLoader do
+describe Resolvers::MergeRequestResolver do
   include GraphqlHelpers
 
   set(:project) { create(:project, :repository) }
@@ -17,7 +17,7 @@ describe Loaders::IidLoader do
   let(:other_full_path) { other_project.full_path }
   let(:other_iid) { other_merge_request.iid }
 
-  describe '.merge_request' do
+  describe '#resolve' do
     it 'batch-resolves merge requests by target project full path and IID' do
       path = full_path # avoid database query
 
@@ -53,6 +53,6 @@ describe Loaders::IidLoader do
   end
 
   def resolve_mr(full_path, iid)
-    resolve(described_class, :merge_request, args: { project: full_path, iid: iid })
+    resolve(described_class, args: { full_path: full_path, iid: iid })
   end
 end
diff --git a/spec/graphql/loaders/full_path_loader_spec.rb b/spec/graphql/resolvers/project_resolver_spec.rb
index 2732dd8c9da..d4990c6492c 100644
--- a/spec/graphql/loaders/full_path_loader_spec.rb
+++ b/spec/graphql/resolvers/project_resolver_spec.rb
@@ -1,6 +1,6 @@
 require 'spec_helper'
 
-describe Loaders::FullPathLoader do
+describe Resolvers::ProjectResolver do
   include GraphqlHelpers
 
   set(:project1) { create(:project) }
@@ -8,7 +8,7 @@ describe Loaders::FullPathLoader do
 
   set(:other_project) { create(:project) }
 
-  describe '.project' do
+  describe '#resolve' do
     it 'batch-resolves projects by full path' do
       paths = [project1.full_path, project2.full_path]
 
@@ -27,6 +27,6 @@ describe Loaders::FullPathLoader do
   end
 
   def resolve_project(full_path)
-    resolve(described_class, :project, args: { full_path: full_path })
+    resolve(described_class, args: { full_path: full_path })
   end
 end
diff --git a/spec/graphql/types/project_type_spec.rb b/spec/graphql/types/project_type_spec.rb
new file mode 100644
index 00000000000..e0f89105b86
--- /dev/null
+++ b/spec/graphql/types/project_type_spec.rb
@@ -0,0 +1,5 @@
+require 'spec_helper'
+
+describe GitlabSchema.types['Project'] do
+  it { expect(described_class.graphql_name).to eq('Project') }
+end
diff --git a/spec/graphql/types/query_type_spec.rb b/spec/graphql/types/query_type_spec.rb
index 17d9395504c..8488252fd59 100644
--- a/spec/graphql/types/query_type_spec.rb
+++ b/spec/graphql/types/query_type_spec.rb
@@ -2,7 +2,7 @@ require 'spec_helper'
 
 describe GitlabSchema.types['Query'] do
   it 'is called Query' do
-    expect(described_class.name).to eq('Query')
+    expect(described_class.graphql_name).to eq('Query')
   end
 
   it { is_expected.to have_graphql_fields(:project, :merge_request, :echo) }
@@ -13,7 +13,7 @@ describe GitlabSchema.types['Query'] do
     it 'finds projects by full path' do
       is_expected.to have_graphql_arguments(:full_path)
       is_expected.to have_graphql_type(Types::ProjectType)
-      is_expected.to have_graphql_resolver(Loaders::FullPathLoader[:project])
+      is_expected.to have_graphql_resolver(Resolvers::ProjectResolver)
     end
 
     it 'authorizes with read_project' do
@@ -22,12 +22,12 @@ describe GitlabSchema.types['Query'] do
   end
 
   describe 'merge_request field' do
-    subject { described_class.fields['merge_request'] }
+    subject { described_class.fields['mergeRequest'] }
 
     it 'finds MRs by project and IID' do
-      is_expected.to have_graphql_arguments(:project, :iid)
+      is_expected.to have_graphql_arguments(:full_path, :iid)
       is_expected.to have_graphql_type(Types::MergeRequestType)
-      is_expected.to have_graphql_resolver(Loaders::IidLoader[:merge_request])
+      is_expected.to have_graphql_resolver(Resolvers::MergeRequestResolver)
     end
 
     it 'authorizes with read_merge_request' do
diff --git a/spec/graphql/types/time_type_spec.rb b/spec/graphql/types/time_type_spec.rb
index 087655cc67d..4196d9d27d4 100644
--- a/spec/graphql/types/time_type_spec.rb
+++ b/spec/graphql/types/time_type_spec.rb
@@ -1,16 +1,16 @@
 require 'spec_helper'
 
 describe GitlabSchema.types['Time'] do
-  let(:float) { 1504630455.96215 }
-  let(:time) { Time.at(float) }
+  let(:iso) { "2018-06-04T15:23:50+02:00" }
+  let(:time) { Time.parse(iso) }
 
-  it { expect(described_class.name).to eq('Time') }
+  it { expect(described_class.graphql_name).to eq('Time') }
 
-  it 'coerces Time into fractional seconds since epoch' do
-    expect(described_class.coerce_isolated_result(time)).to eq(float)
+  it 'coerces Time object into ISO 8601' do
+    expect(described_class.coerce_isolated_result(time)).to eq(iso)
   end
 
-  it 'coerces fractional seconds since epoch into Time' do
-    expect(described_class.coerce_isolated_input(float)).to eq(time)
+  it 'coerces an ISO-time into Time object' do
+    expect(described_class.coerce_isolated_input(iso)).to eq(time)
   end
 end
diff --git a/spec/requests/api/graphql/merge_request_query_spec.rb b/spec/requests/api/graphql/merge_request_query_spec.rb
new file mode 100644
index 00000000000..12b1d5d18a2
--- /dev/null
+++ b/spec/requests/api/graphql/merge_request_query_spec.rb
@@ -0,0 +1,49 @@
+require 'spec_helper'
+
+describe 'getting merge request information' do
+  include GraphqlHelpers
+
+  let(:project) { create(:project, :repository) }
+  let(:merge_request) { create(:merge_request, source_project: project) }
+  let(:current_user) { create(:user) }
+
+  let(:query) do
+    attributes = {
+      'fullPath' => merge_request.project.full_path,
+      'iid' => merge_request.iid
+    }
+    graphql_query_for('mergeRequest',  attributes)
+  end
+
+  context 'when the user has access to the merge request' do
+    before do
+      project.add_developer(current_user)
+      post_graphql(query, current_user: current_user)
+    end
+
+    it 'returns the merge request' do
+      expect(graphql_data['mergeRequest']).not_to be_nil
+    end
+
+    # This is a field coming from the `MergeRequestPresenter`
+    it 'includes a web_url' do
+      expect(graphql_data['mergeRequest']['webUrl']).to be_present
+    end
+
+    it_behaves_like 'a working graphql query'
+  end
+
+  context 'when the user does not have access to the merge request' do
+    before do
+      post_graphql(query, current_user: current_user)
+    end
+
+    it 'returns an empty field' do
+      post_graphql(query, current_user: current_user)
+
+      expect(graphql_data['mergeRequest']).to be_nil
+    end
+
+    it_behaves_like 'a working graphql query'
+  end
+end
diff --git a/spec/requests/api/graphql/project_query_spec.rb b/spec/requests/api/graphql/project_query_spec.rb
new file mode 100644
index 00000000000..8196bcfa87c
--- /dev/null
+++ b/spec/requests/api/graphql/project_query_spec.rb
@@ -0,0 +1,39 @@
+require 'spec_helper'
+
+describe 'getting project information' do
+  include GraphqlHelpers
+
+  let(:project) { create(:project, :repository) }
+  let(:current_user) { create(:user) }
+
+  let(:query) do
+    graphql_query_for('project', 'fullPath' => project.full_path)
+  end
+
+  context 'when the user has access to the project' do
+    before do
+      project.add_developer(current_user)
+      post_graphql(query, current_user: current_user)
+    end
+
+    it 'includes the project' do
+      expect(graphql_data['project']).not_to be_nil
+    end
+
+    it_behaves_like 'a working graphql query'
+  end
+
+  context 'when the user does not have access to the project' do
+    before do
+      post_graphql(query, current_user: current_user)
+    end
+
+    it 'returns an empty field' do
+      post_graphql(query, current_user: current_user)
+
+      expect(graphql_data['project']).to be_nil
+    end
+
+    it_behaves_like 'a working graphql query'
+  end
+end
diff --git a/spec/requests/graphql/merge_request_query_spec.rb b/spec/requests/graphql/merge_request_query_spec.rb
deleted file mode 100644
index cbc19782e2f..00000000000
--- a/spec/requests/graphql/merge_request_query_spec.rb
+++ /dev/null
@@ -1,24 +0,0 @@
-require 'spec_helper'
-
-describe 'getting merge request information' do
-  include GraphqlHelpers
-
-  let(:project) { create(:project, :repository, :public) }
-  let(:merge_request) { create(:merge_request, source_project: project) }
-
-  let(:query) do
-    <<~QUERY
-    {
-      merge_request(project: "#{merge_request.project.full_path}", iid: "#{merge_request.iid}") {
-        #{all_graphql_fields_for(MergeRequest)}
-      }
-    }
-    QUERY
-  end
-
-  it_behaves_like 'a working graphql query' do
-    it 'renders a merge request with all fields' do
-      expect(response_data['merge_request']).not_to be_nil
-    end
-  end
-end
diff --git a/spec/requests/graphql/project_query_spec.rb b/spec/requests/graphql/project_query_spec.rb
deleted file mode 100644
index 110ed433e03..00000000000
--- a/spec/requests/graphql/project_query_spec.rb
+++ /dev/null
@@ -1,23 +0,0 @@
-require 'spec_helper'
-
-describe 'getting project information' do
-  include GraphqlHelpers
-
-  let(:project) { create(:project, :repository, :public) }
-
-  let(:query) do
-    <<~QUERY
-    {
-      project(full_path: "#{project.full_path}") {
-        #{all_graphql_fields_for(Project)}
-      }
-    }
-    QUERY
-  end
-
-  it_behaves_like 'a working graphql query' do
-    it 'renders a project with all fields' do
-      expect(response_data['project']).not_to be_nil
-    end
-  end
-end
diff --git a/spec/routing/api_routing_spec.rb b/spec/routing/api_routing_spec.rb
new file mode 100644
index 00000000000..5fde4bd885b
--- /dev/null
+++ b/spec/routing/api_routing_spec.rb
@@ -0,0 +1,31 @@
+require 'spec_helper'
+
+describe 'api', 'routing' do
+  context 'when graphql is disabled' do
+    before do
+      stub_feature_flags(graphql: false)
+    end
+
+    it 'does not route to the GraphqlController' do
+      expect(get('/api/graphql')).not_to route_to('graphql#execute')
+    end
+
+    it 'does not expose graphiql' do
+      expect(get('/-/graphql-explorer')).not_to route_to('graphiql/rails/editors#show')
+    end
+  end
+
+  context 'when graphql is disabled' do
+    before do
+      stub_feature_flags(graphql: true)
+    end
+
+    it 'routes to the GraphqlController' do
+      expect(get('/api/graphql')).not_to route_to('graphql#execute')
+    end
+
+    it 'exposes graphiql' do
+      expect(get('/-/graphql-explorer')).not_to route_to('graphiql/rails/editors#show')
+    end
+  end
+end
diff --git a/spec/support/helpers/graphql_helpers.rb b/spec/support/helpers/graphql_helpers.rb
index ae29b16e32c..30ff9a1196a 100644
--- a/spec/support/helpers/graphql_helpers.rb
+++ b/spec/support/helpers/graphql_helpers.rb
@@ -1,7 +1,16 @@
 module GraphqlHelpers
+  # makes an underscored string look like a fieldname
+  # "merge_request" => "mergeRequest"
+  def self.fieldnamerize(underscored_field_name)
+    graphql_field_name = underscored_field_name.to_s.camelize
+    graphql_field_name[0] = graphql_field_name[0].downcase
+
+    graphql_field_name
+  end
+
   # Run a loader's named resolver
-  def resolve(kls, name, obj: nil, args: {}, ctx: {})
-    kls[name].call(obj, args, ctx)
+  def resolve(resolver_class, obj: nil, args: {}, ctx: {})
+    resolver_class.new(object: obj, context: ctx).resolve(args)
   end
 
   # Runs a block inside a BatchLoader::Executor wrapper
@@ -24,8 +33,20 @@ module GraphqlHelpers
     end
   end
 
-  def all_graphql_fields_for(klass)
-    type = GitlabSchema.types[klass.name]
+  def graphql_query_for(name, attributes = {}, fields = nil)
+    fields ||= all_graphql_fields_for(name.classify)
+    attributes = attributes_to_graphql(attributes)
+    <<~QUERY
+    {
+      #{name}(#{attributes}) {
+        #{fields}
+      }
+    }
+    QUERY
+  end
+
+  def all_graphql_fields_for(class_name)
+    type = GitlabSchema.types[class_name.to_s]
     return "" unless type
 
     type.fields.map do |name, field|
@@ -37,8 +58,22 @@ module GraphqlHelpers
     end.join("\n")
   end
 
-  def post_graphql(query)
-    post '/api/graphql', query: query
+  def attributes_to_graphql(attributes)
+    attributes.map do |name, value|
+      "#{GraphqlHelpers.fieldnamerize(name.to_s)}: \"#{value}\""
+    end.join(", ")
+  end
+
+  def post_graphql(query, current_user: nil)
+    post api('/', current_user, version: 'graphql'), query: query
+  end
+
+  def graphql_data
+    json_response['data']
+  end
+
+  def graphql_errors
+    json_response['data']
   end
 
   def scalar?(field)
diff --git a/spec/support/matchers/graphql_matchers.rb b/spec/support/matchers/graphql_matchers.rb
index c0ed16ecaba..ba7a1c8cde0 100644
--- a/spec/support/matchers/graphql_matchers.rb
+++ b/spec/support/matchers/graphql_matchers.rb
@@ -1,31 +1,40 @@
 RSpec::Matchers.define :require_graphql_authorizations do |*expected|
   match do |field|
-    authorizations = field.metadata[:authorize]
-
-    expect(authorizations).to contain_exactly(*expected)
+    field_definition = field.metadata[:type_class]
+    expect(field_definition).to respond_to(:required_permissions)
+    expect(field_definition.required_permissions).to contain_exactly(*expected)
   end
 end
 
 RSpec::Matchers.define :have_graphql_fields do |*expected|
   match do |kls|
-    expect(kls.fields.keys).to contain_exactly(*expected.map(&:to_s))
+    field_names = expected.map { |name| GraphqlHelpers.fieldnamerize(name) }
+    expect(kls.fields.keys).to contain_exactly(*field_names)
   end
 end
 
 RSpec::Matchers.define :have_graphql_arguments do |*expected|
+  include GraphqlHelpers
+
   match do |field|
-    expect(field.arguments.keys).to contain_exactly(*expected.map(&:to_s))
+    argument_names = expected.map { |name| GraphqlHelpers.fieldnamerize(name) }
+    expect(field.arguments.keys).to contain_exactly(*argument_names)
   end
 end
 
 RSpec::Matchers.define :have_graphql_type do |expected|
   match do |field|
-    expect(field.type).to eq(expected)
+    expect(field.type).to eq(expected.to_graphql)
   end
 end
 
 RSpec::Matchers.define :have_graphql_resolver do |expected|
   match do |field|
-    expect(field.resolve_proc).to eq(expected)
+    case expected
+    when Method
+      expect(field.metadata[:type_class].resolve_proc).to eq(expected)
+    else
+      expect(field.metadata[:type_class].resolver).to eq(expected)
+    end
   end
 end
diff --git a/spec/support/shared_examples/requests/graphql_shared_examples.rb b/spec/support/shared_examples/requests/graphql_shared_examples.rb
index c143b83696e..9b2b74593a5 100644
--- a/spec/support/shared_examples/requests/graphql_shared_examples.rb
+++ b/spec/support/shared_examples/requests/graphql_shared_examples.rb
@@ -3,16 +3,9 @@ require 'spec_helper'
 shared_examples 'a working graphql query' do
   include GraphqlHelpers
 
-  let(:parsed_response) { JSON.parse(response.body) }
-  let(:response_data) { parsed_response['data'] }
-
-  before do
-    post_graphql(query)
-  end
-
   it 'is returns a successfull response', :aggregate_failures do
     expect(response).to be_success
-    expect(parsed_response['errors']).to be_nil
-    expect(response_data).not_to be_empty
+    expect(graphql_errors['errors']).to be_nil
+    expect(json_response.keys).to include('data')
   end
 end