1 files changed, 135 insertions, 0 deletions
diff --git a/lib/api/concerns/packages/nuget_endpoints.rb b/lib/api/concerns/packages/nuget_endpoints.rb
new file mode 100644
index 00000000000..5177c4d23c0
--- /dev/null
+++ b/lib/api/concerns/packages/nuget_endpoints.rb
@@ -0,0 +1,135 @@
+# frozen_string_literal: true
+#
+# NuGet Package Manager Client API
+#
+# These API endpoints are not consumed directly by users, so there is no documentation for the
+# individual endpoints. They are called by the NuGet package manager client when users run commands
+# like `nuget install` or `nuget push`. The usage of the GitLab NuGet registry is documented here:
+# https://docs.gitlab.com/ee/user/packages/nuget_repository/
+#
+# Technical debt: https://gitlab.com/gitlab-org/gitlab/issues/35798
+module API
+  module Concerns
+    module Packages
+      module NugetEndpoints
+        extend ActiveSupport::Concern
+
+        POSITIVE_INTEGER_REGEX = %r{\A[1-9]\d*\z}.freeze
+        NON_NEGATIVE_INTEGER_REGEX = %r{\A0|[1-9]\d*\z}.freeze
+
+        included do
+          helpers do
+            def find_packages
+              packages = package_finder.execute
+
+              not_found!('Packages') unless packages.exists?
+
+              packages
+            end
+
+            def find_package
+              package = package_finder(package_version: params[:package_version]).execute
+                                                                                 .first
+
+              not_found!('Package') unless package
+
+              package
+            end
+
+            def package_finder(finder_params = {})
+              ::Packages::Nuget::PackageFinder.new(
+                authorized_user_project,
+                **finder_params.merge(package_name: params[:package_name])
+              )
+            end
+          end
+
+          # https://docs.microsoft.com/en-us/nuget/api/service-index
+          desc 'The NuGet Service Index' do
+            detail 'This feature was introduced in GitLab 12.6'
+          end
+
+          route_setting :authentication, deploy_token_allowed: true, job_token_allowed: :basic_auth, basic_auth_personal_access_token: true
+
+          get 'index', format: :json do
+            authorize_read_package!(authorized_user_project)
+            track_package_event('cli_metadata', :nuget, category: 'API::NugetPackages')
+
+            present ::Packages::Nuget::ServiceIndexPresenter.new(authorized_user_project),
+              with: ::API::Entities::Nuget::ServiceIndex
+          end
+
+          # https://docs.microsoft.com/en-us/nuget/api/registration-base-url-resource
+          params do
+            requires :package_name, type: String, desc: 'The NuGet package name', regexp: API::NO_SLASH_URL_PART_REGEX
+          end
+          namespace '/metadata/*package_name' do
+            before do
+              authorize_read_package!(authorized_user_project)
+            end
+
+            desc 'The NuGet Metadata Service - Package name level' do
+              detail 'This feature was introduced in GitLab 12.8'
+            end
+
+            route_setting :authentication, deploy_token_allowed: true, job_token_allowed: :basic_auth, basic_auth_personal_access_token: true
+
+            get 'index', format: :json do
+              present ::Packages::Nuget::PackagesMetadataPresenter.new(find_packages),
+                      with: ::API::Entities::Nuget::PackagesMetadata
+            end
+
+            desc 'The NuGet Metadata Service - Package name and version level' do
+              detail 'This feature was introduced in GitLab 12.8'
+            end
+            params do
+              requires :package_version, type: String, desc: 'The NuGet package version', regexp: API::NO_SLASH_URL_PART_REGEX
+            end
+
+            route_setting :authentication, deploy_token_allowed: true, job_token_allowed: :basic_auth, basic_auth_personal_access_token: true
+
+            get '*package_version', format: :json do
+              present ::Packages::Nuget::PackageMetadataPresenter.new(find_package),
+                      with: ::API::Entities::Nuget::PackageMetadata
+            end
+          end
+
+          # https://docs.microsoft.com/en-us/nuget/api/search-query-service-resource
+          params do
+            requires :q, type: String, desc: 'The search term'
+            optional :skip, type: Integer, desc: 'The number of results to skip', default: 0, regexp: NON_NEGATIVE_INTEGER_REGEX
+            optional :take, type: Integer, desc: 'The number of results to return', default: Kaminari.config.default_per_page, regexp: POSITIVE_INTEGER_REGEX
+            optional :prerelease, type: ::Grape::API::Boolean, desc: 'Include prerelease versions', default: true
+          end
+          namespace '/query' do
+            before do
+              authorize_read_package!(authorized_user_project)
+            end
+
+            desc 'The NuGet Search Service' do
+              detail 'This feature was introduced in GitLab 12.8'
+            end
+
+            route_setting :authentication, deploy_token_allowed: true, job_token_allowed: :basic_auth, basic_auth_personal_access_token: true
+
+            get format: :json do
+              search_options = {
+                include_prerelease_versions: params[:prerelease],
+                per_page: params[:take],
+                padding: params[:skip]
+              }
+              search = ::Packages::Nuget::SearchService
+                .new(authorized_user_project, params[:q], search_options)
+                .execute
+
+              track_package_event('search_package', :nuget, category: 'API::NugetPackages')
+
+              present ::Packages::Nuget::SearchResultsPresenter.new(search),
+                with: ::API::Entities::Nuget::SearchResults
+            end
+          end
+        end
+      end
+    end
+  end
+end