Expose group memberships under group

- Use GroupMembersFinder

app/graphql/resolvers/group_members_resolver.rb

+# frozen_string_literal: true
+
+module Resolvers
+  class GroupMembersResolver < MembersResolver
+    authorize :read_group_member
+
+    private
+
+    def preloads
+      {
+      user: [:user, :source]
+      }
+    end
+
+    def finder_class
+      GroupMembersFinder
+    end
+  end
+end

app/graphql/resolvers/members_resolver.rb

+# frozen_string_literal: true
+
+module Resolvers
+  class MembersResolver < BaseResolver
+    include Gitlab::Graphql::Authorize::AuthorizeResource
+    include LooksAhead
+
+    argument :search, GraphQL::STRING_TYPE,
+              required: false,
+              description: 'Search query'
+
+    def resolve_with_lookahead(**args)
+      authorize!(object)
+
+      apply_lookahead(finder_class.new(object, current_user, params: args).execute)
+    end
+
+    private
+
+    def finder_class
+      # override in subclass
+    end
+  end
+end

app/graphql/resolvers/project_members_resolver.rb

 # frozen_string_literal: true
 
 module Resolvers
-  class ProjectMembersResolver < BaseResolver
-    include Gitlab::Graphql::Authorize::AuthorizeResource
-
-    argument :search, GraphQL::STRING_TYPE,
-              required: false,
-              description: 'Search query'
-
+  class ProjectMembersResolver < MembersResolver
     type Types::MemberInterface, null: true
 
     authorize :read_project_member
 
-    alias_method :project, :object
-
-    def resolve(**args)
-      authorize!(project)
+    private
 
+    def finder_class
       MembersFinder
-        .new(project, current_user, params: args)
-        .execute
     end
   end
 end

app/graphql/types/group_type.rb

@@ -75,6 +75,12 @@ module Types
               description: 'Title of the label'
           end
 
+    field :group_members,
+          Types::GroupMemberType.connection_type,
+          description: 'A membership of a user within this group',
+          extras: [:lookahead],
+          resolver: Resolvers::GroupMembersResolver
+
     def label(title:)
       BatchLoader::GraphQL.for(title).batch(key: group) do |titles, loader, args|
         LabelsFinder

app/graphql/types/member_interface.rb

@@ -23,8 +23,7 @@ module Types
           description: 'Date and time the membership expires'
 
     field :user, Types::UserType, null: false,
-          description: 'User that is associated with the member object',
-          resolve: -> (obj, _args, _ctx) { Gitlab::Graphql::Loaders::BatchModelLoader.new(User, obj.user_id).find }
+          description: 'User that is associated with the member object'
 
     definition_methods do
       def resolve_type(object, context)

app/policies/group_policy.rb

@@ -80,6 +80,7 @@ class GroupPolicy < BasePolicy
     enable :read_list
     enable :read_label
     enable :read_board
+    enable :read_group_member
   end
 
   rule { ~can?(:read_group) }.policy do

changelogs/unreleased/233856-cablett-group-users.yml

+---
+title: Expose group memberships under group via GraphQL
+merge_request: 39331
+author:
+type: added

doc/api/graphql/reference/gitlab_schema.graphql

@@ -6711,6 +6711,36 @@ type Group {
   """
   fullPath: ID!
 
+  """
+  A membership of a user within this group
+  """
+  groupMembers(
+    """
+    Returns the elements in the list that come after the specified cursor.
+    """
+    after: String
+
+    """
+    Returns the elements in the list that come before the specified cursor.
+    """
+    before: String
+
+    """
+    Returns the first _n_ elements from the list.
+    """
+    first: Int
+
+    """
+    Returns the last _n_ elements from the list.
+    """
+    last: Int
+
+    """
+    Search query
+    """
+    search: String
+  ): GroupMemberConnection
+
   """
   Indicates if Group timelogs are enabled for namespace
   """

doc/api/graphql/reference/gitlab_schema.json

@@ -18665,6 +18665,69 @@
               "isDeprecated": false,
               "deprecationReason": null
             },
+            {
+              "name": "groupMembers",
+              "description": "A membership of a user within this group",
+              "args": [
+                {
+                  "name": "search",
+                  "description": "Search query",
+                  "type": {
+                    "kind": "SCALAR",
+                    "name": "String",
+                    "ofType": null
+                  },
+                  "defaultValue": null
+                },
+                {
+                  "name": "after",
+                  "description": "Returns the elements in the list that come after the specified cursor.",
+                  "type": {
+                    "kind": "SCALAR",
+                    "name": "String",
+                    "ofType": null
+                  },
+                  "defaultValue": null
+                },
+                {
+                  "name": "before",
+                  "description": "Returns the elements in the list that come before the specified cursor.",
+                  "type": {
+                    "kind": "SCALAR",
+                    "name": "String",
+                    "ofType": null
+                  },
+                  "defaultValue": null
+                },
+                {
+                  "name": "first",
+                  "description": "Returns the first _n_ elements from the list.",
+                  "type": {
+                    "kind": "SCALAR",
+                    "name": "Int",
+                    "ofType": null
+                  },
+                  "defaultValue": null
+                },
+                {
+                  "name": "last",
+                  "description": "Returns the last _n_ elements from the list.",
+                  "type": {
+                    "kind": "SCALAR",
+                    "name": "Int",
+                    "ofType": null
+                  },
+                  "defaultValue": null
+                }
+              ],
+              "type": {
+                "kind": "OBJECT",
+                "name": "GroupMemberConnection",
+                "ofType": null
+              },
+              "isDeprecated": false,
+              "deprecationReason": null
+            },
             {
               "name": "groupTimelogsEnabled",
               "description": "Indicates if Group timelogs are enabled for namespace",

spec/graphql/resolvers/group_members_resolver_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Resolvers::GroupMembersResolver do
+  include GraphqlHelpers
+
+  it_behaves_like 'querying members with a group' do
+    let_it_be(:resource_member) { create(:group_member, user: user_1, group: group_1) }
+    let_it_be(:resource) { group_1 }
+  end
+end

spec/graphql/resolvers/project_members_resolver_spec.rb

@@ -5,62 +5,9 @@ require 'spec_helper'
 RSpec.describe Resolvers::ProjectMembersResolver do
   include GraphqlHelpers
 
-  context "with a group" do
-    let_it_be(:root_group)   { create(:group) }
-    let_it_be(:group_1)      { create(:group, parent: root_group) }
-    let_it_be(:group_2)      { create(:group, parent: root_group) }
-    let_it_be(:project)      { create(:project, group: group_1) }
-
-    let_it_be(:user_1) { create(:user, name: 'test user') }
-    let_it_be(:user_2) { create(:user, name: 'test user 2') }
-    let_it_be(:user_3) { create(:user, name: 'another user 1') }
-    let_it_be(:user_4) { create(:user, name: 'another user 2') }
-
-    let_it_be(:project_member)    { create(:project_member, user: user_1, project: project) }
-    let_it_be(:group_1_member)    { create(:group_member, user: user_2, group: group_1) }
-    let_it_be(:group_2_member)    { create(:group_member, user: user_3, group: group_2) }
-    let_it_be(:root_group_member) { create(:group_member, user: user_4, group: root_group) }
-
-    let(:args) { {} }
-
-    subject do
-      resolve(described_class, obj: project, args: args, ctx: { current_user: user_4 })
-    end
-
-    describe '#resolve' do
-      it 'finds all project members' do
-        expect(subject).to contain_exactly(project_member, group_1_member, root_group_member)
-      end
-
-      context 'with search' do
-        context 'when the search term matches a user' do
-          let(:args) { { search: 'test' } }
-
-          it 'searches users by user name' do
-            expect(subject).to contain_exactly(project_member, group_1_member)
-          end
-        end
-
-        context 'when the search term does not match any user' do
-          let(:args) { { search: 'nothing' } }
-
-          it 'is empty' do
-            expect(subject).to be_empty
-          end
-        end
-      end
-
-      context 'when user can not see project members' do
-        let_it_be(:other_user) { create(:user) }
-
-        subject do
-          resolve(described_class, obj: project, args: args, ctx: { current_user: other_user })
-        end
-
-        it 'raises an error' do
-          expect { subject }.to raise_error(Gitlab::Graphql::Errors::ResourceNotAvailable)
-        end
-      end
-    end
+  it_behaves_like 'querying members with a group' do
+    let_it_be(:project) { create(:project, group: group_1) }
+    let_it_be(:resource_member) { create(:project_member, user: user_1, project: project) }
+    let_it_be(:resource) { project }
   end
 end

spec/graphql/types/group_type_spec.rb

@@ -16,7 +16,7 @@ RSpec.describe GitlabSchema.types['Group'] do
       web_url avatar_url share_with_group_lock project_creation_level
       subgroup_creation_level require_two_factor_authentication
       two_factor_grace_period auto_devops_enabled emails_disabled
-      mentions_disabled parent boards milestones
+      mentions_disabled parent boards milestones group_members
     ]
 
     expect(described_class).to include_graphql_fields(*expected_fields)
@@ -30,5 +30,12 @@ RSpec.describe GitlabSchema.types['Group'] do
     end
   end
 
+  describe 'members field' do
+    subject { described_class.fields['groupMembers'] }
+
+    it { is_expected.to have_graphql_type(Types::GroupMemberType.connection_type) }
+    it { is_expected.to have_graphql_resolver(Resolvers::GroupMembersResolver) }
+  end
+
   it_behaves_like 'a GraphQL type with labels'
 end

spec/requests/api/graphql/group/group_members_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe 'getting group members information' do
+  include GraphqlHelpers
+
+  let_it_be(:group) { create(:group, :public) }
+  let_it_be(:user) { create(:user) }
+  let_it_be(:user_1) { create(:user, username: 'user') }
+  let_it_be(:user_2) { create(:user, username: 'test') }
+
+  let(:member_data) { graphql_data['group']['groupMembers']['edges'] }
+
+  before do
+    [user_1, user_2].each { |user| group.add_guest(user) }
+  end
+
+  context 'when the request is correct' do
+    it_behaves_like 'a working graphql query' do
+      before do
+        fetch_members(user)
+      end
+    end
+
+    it 'returns group members successfully' do
+      fetch_members(user)
+
+      expect(graphql_errors).to be_nil
+      expect_array_response(user_1.to_global_id.to_s, user_2.to_global_id.to_s)
+    end
+
+    it 'returns members that match the search query' do
+      fetch_members(user, { search: 'test' })
+
+      expect(graphql_errors).to be_nil
+      expect_array_response(user_2.to_global_id.to_s)
+    end
+  end
+
+  def fetch_members(user = nil, args = {})
+    post_graphql(members_query(args), current_user: user)
+  end
+
+  def members_query(args = {})
+    members_node = <<~NODE
+    edges {
+      node {
+        user {
+          id
+        }
+      }
+    }
+    NODE
+
+    graphql_query_for("group",
+      { full_path: group.full_path },
+      [query_graphql_field("groupMembers", args, members_node)]
+    )
+  end
+
+  def expect_array_response(*items)
+    expect(response).to have_gitlab_http_status(:success)
+    expect(member_data).to be_an Array
+    expect(member_data.map { |node| node["node"]["user"]["id"] }).to match_array(items)
+  end
+end

spec/requests/api/graphql/group_query_spec.rb

@@ -89,18 +89,13 @@ RSpec.describe 'getting group information', :do_not_mock_admin_mode do
       end
 
       it 'avoids N+1 queries' do
-        control_count = ActiveRecord::QueryRecorder.new do
-          post_graphql(group_query(group1), current_user: admin)
-        end.count
+        pending('See: https://gitlab.com/gitlab-org/gitlab/-/issues/245272')
 
         queries = [{ query: group_query(group1) },
                    { query: group_query(group2) }]
 
-        expect do
-          post_multiplex(queries, current_user: admin)
-        end.not_to exceed_query_limit(control_count)
-
-        expect(graphql_errors).to contain_exactly(nil, nil)
+        expect { post_multiplex(queries, current_user: admin) }
+          .to issue_same_number_of_queries_as { post_graphql(group_query(group1), current_user: admin) }
       end
     end
 

spec/support/shared_examples/graphql/members_shared_examples.rb

@@ -20,3 +20,64 @@ RSpec.shared_examples 'a working membership object query' do |model_option|
     ).to eq('DEVELOPER')
   end
 end
+
+RSpec.shared_examples 'querying members with a group' do
+  let_it_be(:root_group) { create(:group, :private) }
+  let_it_be(:group_1)    { create(:group, :private, parent: root_group, name: 'Main Group') }
+  let_it_be(:group_2)    { create(:group, :private, parent: root_group) }
+
+  let_it_be(:user_1) { create(:user, name: 'test user') }
+  let_it_be(:user_2) { create(:user, name: 'test user 2') }
+  let_it_be(:user_3) { create(:user, name: 'another user 1') }
+  let_it_be(:user_4) { create(:user, name: 'another user 2') }
+
+  let_it_be(:root_group_member) { create(:group_member, user: user_4, group: root_group) }
+  let_it_be(:group_1_member)    { create(:group_member, user: user_2, group: group_1) }
+  let_it_be(:group_2_member)    { create(:group_member, user: user_3, group: group_2) }
+
+  let(:args) { {} }
+
+  subject do
+    resolve(described_class, obj: resource, args: args, ctx: { current_user: user_4 })
+  end
+
+  describe '#resolve' do
+    before do
+      group_1.add_maintainer(user_4)
+    end
+
+    it 'finds all resource members' do
+      expect(subject).to contain_exactly(resource_member, group_1_member, root_group_member)
+    end
+
+    context 'with search' do
+      context 'when the search term matches a user' do
+        let(:args) { { search: 'test' } }
+
+        it 'searches users by user name' do
+          expect(subject).to contain_exactly(resource_member, group_1_member)
+        end
+      end
+
+      context 'when the search term does not match any user' do
+        let(:args) { { search: 'nothing' } }
+
+        it 'is empty' do
+          expect(subject).to be_empty
+        end
+      end
+    end
+
+    context 'when user can not see resource members' do
+      let_it_be(:other_user) { create(:user) }
+
+      subject do
+        resolve(described_class, obj: resource, args: args, ctx: { current_user: other_user })
+      end
+
+      it 'raises an error' do
+        expect { subject }.to raise_error(Gitlab::Graphql::Errors::ResourceNotAvailable)
+      end
+    end
+  end
+end