Add GraphQL mutation to delete release asset link

This commit adds a new mutation - `releaseAssetLinkDelete` - that
deletes a release asset link.

app/graphql/mutations/release_asset_links/delete.rb

+# frozen_string_literal: true
+
+module Mutations
+  module ReleaseAssetLinks
+    class Delete < BaseMutation
+      graphql_name 'ReleaseAssetLinkDelete'
+
+      authorize :destroy_release
+
+      ReleaseAssetLinkID = ::Types::GlobalIDType[::Releases::Link]
+
+      argument :id, ReleaseAssetLinkID,
+               required: true,
+               description: 'ID of the release asset link to delete.'
+
+      field :link,
+            Types::ReleaseAssetLinkType,
+            null: true,
+            description: 'The deleted release asset link.'
+
+      def resolve(id:)
+        link = authorized_find!(id)
+
+        unless link.destroy
+          return { link: nil, errors: link.errors.full_messages }
+        end
+
+        { link: link, errors: [] }
+      end
+
+      def find_object(id)
+        # TODO: remove this line when the compatibility layer is removed
+        # See: https://gitlab.com/gitlab-org/gitlab/-/issues/257883
+        id = ReleaseAssetLinkID.coerce_isolated_input(id)
+
+        GitlabSchema.find_by_gid(id)
+      end
+    end
+  end
+end

app/graphql/types/mutation_type.rb

@@ -68,6 +68,7 @@ module Types
     mount_mutation Mutations::Releases::Delete
     mount_mutation Mutations::ReleaseAssetLinks::Create
     mount_mutation Mutations::ReleaseAssetLinks::Update
+    mount_mutation Mutations::ReleaseAssetLinks::Delete
     mount_mutation Mutations::Terraform::State::Delete
     mount_mutation Mutations::Terraform::State::Lock
     mount_mutation Mutations::Terraform::State::Unlock

changelogs/unreleased/nfriend-add-release-asset-link-delete-mutation.yml

+---
+title: Add GraphQL mutation to delete an existing release asset link
+merge_request: 56417
+author:
+type: added

doc/api/graphql/reference/index.md

@@ -5032,6 +5032,16 @@ Autogenerated return type of ReleaseAssetLinkCreate.
 | `errors` | [`[String!]!`](#string) | Errors encountered during execution of the mutation. |
 | `link` | [`ReleaseAssetLink`](#releaseassetlink) | The asset link after mutation. |
 
+### `ReleaseAssetLinkDeletePayload`
+
+Autogenerated return type of ReleaseAssetLinkDelete.
+
+| Field | Type | Description |
+| ----- | ---- | ----------- |
+| `clientMutationId` | [`String`](#string) | A unique identifier for the client performing the mutation. |
+| `errors` | [`[String!]!`](#string) | Errors encountered during execution of the mutation. |
+| `link` | [`ReleaseAssetLink`](#releaseassetlink) | The deleted release asset link. |
+
 ### `ReleaseAssetLinkEdge`
 
 An edge in a connection.

spec/graphql/mutations/release_asset_links/delete_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Mutations::ReleaseAssetLinks::Delete do
+  include GraphqlHelpers
+
+  let_it_be(:project) { create(:project, :private, :repository) }
+  let_it_be_with_reload(:release) { create(:release, project: project) }
+  let_it_be(:developer) { create(:user).tap { |u| project.add_developer(u) } }
+  let_it_be(:maintainer) { create(:user).tap { |u| project.add_maintainer(u) } }
+  let_it_be_with_reload(:release_link) { create(:release_link, release: release) }
+
+  let(:mutation) { described_class.new(object: nil, context: { current_user: current_user }, field: nil) }
+  let(:mutation_arguments) { { id: release_link.to_global_id } }
+
+  describe '#resolve' do
+    subject(:resolve) do
+      mutation.resolve(**mutation_arguments)
+    end
+
+    let(:deleted_link) { subject[:link] }
+
+    context 'when the current user has access to delete the link' do
+      let(:current_user) { maintainer }
+
+      it 'deletes the link and returns it', :aggregate_failures do
+        expect(deleted_link).to eq(release_link)
+
+        expect(release.links).to be_empty
+      end
+
+      context "when the link doesn't exist" do
+        let(:mutation_arguments) { super().merge(id: "gid://gitlab/Releases::Link/#{non_existing_record_id}") }
+
+        it 'raises an error' do
+          expect { subject }.to raise_error(Gitlab::Graphql::Errors::ResourceNotAvailable)
+        end
+      end
+
+      context "when the provided ID is invalid" do
+        let(:mutation_arguments) { super().merge(id: 'not-a-valid-gid') }
+
+        it 'raises an error' do
+          expect { subject }.to raise_error(::GraphQL::CoercionError)
+        end
+      end
+    end
+
+    context 'when the current user does not have access to delete the link' do
+      let(:current_user) { developer }
+
+      it 'raises an error' do
+        expect { subject }.to raise_error(Gitlab::Graphql::Errors::ResourceNotAvailable)
+      end
+    end
+  end
+end

spec/requests/api/graphql/mutations/release_asset_links/delete_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe 'Deletes a release asset link' do
+  include GraphqlHelpers
+
+  let_it_be(:project) { create(:project, :private, :repository) }
+  let_it_be(:release) { create(:release, project: project) }
+  let_it_be(:maintainer) { create(:user).tap { |u| project.add_maintainer(u) } }
+  let_it_be(:release_link) { create(:release_link, release: release) }
+
+  let(:current_user) { maintainer }
+  let(:mutation_name) { :release_asset_link_delete }
+  let(:mutation_arguments) { { id: release_link.to_global_id.to_s } }
+
+  let(:mutation) do
+    graphql_mutation(mutation_name, mutation_arguments, <<~FIELDS)
+      link {
+        id
+        name
+        url
+        linkType
+        directAssetUrl
+        external
+      }
+      errors
+    FIELDS
+  end
+
+  let(:delete_link) { post_graphql_mutation(mutation, current_user: current_user) }
+  let(:mutation_response) { graphql_mutation_response(mutation_name)&.with_indifferent_access }
+
+  it 'deletes the release asset link and returns the deleted link', :aggregate_failures do
+    delete_link
+
+    expected_response = {
+      id: release_link.to_global_id.to_s,
+      name: release_link.name,
+      url: release_link.url,
+      linkType: release_link.link_type.upcase,
+      directAssetUrl: end_with(release_link.filepath),
+      external: true
+    }.with_indifferent_access
+
+    expect(mutation_response[:link]).to match(expected_response)
+    expect(mutation_response[:errors]).to eq([])
+  end
+end