Maintenance: Add GraphQL helpers to convert Global IDs to Internal ID…

…s without SQL query

app/graphql/gql/zammad_schema.rb

@@ -41,17 +41,17 @@ def self.resolve_type(abstract_type, obj, _ctx)
 
   # Relay-style Object Identification:
 
-  # Return a string UUID for the internal ID.
+  # Return a string GUID for the internal ID.
   def self.id_from_internal_id(klass, internal_id)
     GlobalID.new(::URI::GID.build(app: GlobalID.app, model_name: klass.to_s, model_id: internal_id)).to_s
   end
 
-  # Return a string UUID for `object`
+  # Return a string GUID for `object`
   def self.id_from_object(object, _type_definition = nil, _query_ctx = nil)
     object.to_global_id.to_s
   end
 
-  # Given a string UUID, find the object.
+  # Given a string GUID, find the object.
   def self.object_from_id(id, _query_ctx = nil, type: ActiveRecord::Base)
     GlobalID.find(id, only: type)
   end
@@ -72,6 +72,42 @@ def self.authorized_object_from_id(id, type:, user:, query: :show?)
     end
   end
 
+  # Given a string GUID, extract the internal ID.
+  # This is very helpful if GUIDs have to be converted en-masse and then authorized in bulk using a scope.
+  # Meanwhile using .object_from_id family would load (and, optionally, authorize) objects one by one.
+  # Beware there's no built-in way to authorize given IDs in this method!
+  #
+  # @param id [String] GUID
+  # @param type [Class] optionally filter to specific class only
+  #
+  # @return [Integer, nil]
+  def self.internal_id_from_id(id, type: ActiveRecord::Base)
+    internal_ids_from_ids([id], type:).first
+  end
+
+  # Given an array of string GUIDs, extract the internal IDs
+  # @see .internal_id_from_id
+  #
+  # @param ids [Array<String>] GUIDs
+  # @param type [Class] optionally filter to specific class only
+  #
+  # @return [Array<Integer>]
+  def self.internal_ids_from_ids(...)
+    local_uris_from_ids(...).map { |uri| uri.model_id.to_i }
+  end
+
+  # Given an array of string GUIDs, return GUID instances
+  #
+  # @param ids [Array<String>] GUIDs
+  # @param type [Class] optionally filter to specific class only
+  #
+  # @return [Array<GlobalID>]
+  def self.local_uris_from_ids(ids, type: ActiveRecord::Base)
+    ids
+      .map { |id| GlobalID.parse id }
+      .select { |uri| (klass = uri.model_name.safe_constantize) && klass <= type }
+  end
+
   def self.unauthorized_object(error)
     raise Exceptions::Forbidden, error.message # Add a top-level error to the response instead of returning nil.
   end

spec/graphql/gql/zammad_schema_global_id_spec.rb

@@ -4,19 +4,77 @@
 
 RSpec.describe Gql::ZammadSchema, type: :graphql do
 
-  it 'generates GraphQL::ID values' do
-    expect(described_class.id_from_object(Ticket.first)).to eq('gid://zammad/Ticket/1')
+  describe '.id_from_object' do
+    it 'generates GraphQL::ID values' do
+      expect(described_class.id_from_object(Ticket.first)).to eq('gid://zammad/Ticket/1')
+    end
   end
 
-  it 'resolves GraphQL::ID values' do
-    expect(described_class.object_from_id('gid://zammad/Ticket/1')).to eq(Ticket.first)
+  describe '.object_from_id' do
+    it 'resolves GraphQL::ID values' do
+      expect(described_class.object_from_id('gid://zammad/Ticket/1')).to eq(Ticket.first)
+    end
   end
 
-  it 'resolves internal IDs to GraphQL::IDs' do
-    expect(described_class.id_from_internal_id(Ticket, 1)).to eq('gid://zammad/Ticket/1')
+  describe '.id_from_internal_id' do
+    it 'resolves internal IDs to GraphQL::IDs' do
+      expect(described_class.id_from_internal_id(Ticket, 1)).to eq('gid://zammad/Ticket/1')
+    end
+
+    it 'resolves internal IDs to GraphQL::IDs (with class name as string)' do
+      expect(described_class.id_from_internal_id('Ticket', 1)).to eq('gid://zammad/Ticket/1')
+    end
+  end
+
+  describe '.internal_id_from_id' do
+    let(:id)         { [*(1..999)].sample }
+    let(:gid_string) { "gid://zammad/Ticket/#{id}" }
+
+    it 'returns internal ID based on given global ID' do
+      expect(described_class.internal_id_from_id(gid_string)).to eq(id)
+    end
+
+    it 'returns nil if class is not allowed' do
+      expect(described_class.internal_id_from_id(gid_string, type: User)).to be_nil
+    end
+
+    it 'returns internal ID if class is allowed' do
+      expect(described_class.internal_id_from_id(gid_string, type: Ticket)).to eq(id)
+    end
+  end
+
+  describe '.internal_ids_from_ids' do
+    let(:id)         { [*(1..999)].sample }
+    let(:gid_string) { "gid://zammad/Ticket/#{id}" }
+
+    it 'returns internal IDs based on given global IDs' do
+      expect(described_class.internal_ids_from_ids([gid_string])).to eq([id])
+    end
+
+    it 'returns internal IDs if class is allowed' do
+      expect(described_class.internal_ids_from_ids([gid_string], type: Ticket)).to eq([id])
+    end
+
+    it 'skips item if class is not allowed' do
+      expect(described_class.internal_ids_from_ids([gid_string], type: User)).to be_blank
+    end
   end
 
-  it 'resolves internal IDs to GraphQL::IDs (with class name as string)' do
-    expect(described_class.id_from_internal_id('Ticket', 1)).to eq('gid://zammad/Ticket/1')
+  describe '.local_uris_from_ids' do
+    let(:id)         { [*(1..999)].sample }
+    let(:gid_string) { "gid://zammad/Ticket/#{id}" }
+    let(:gid)        { GlobalID.new(gid_string) }
+
+    it 'returns given global ID as GlobalID' do
+      expect(described_class.local_uris_from_ids([gid_string])).to eq([gid])
+    end
+
+    it 'returns given global ID if class is allowed' do
+      expect(described_class.local_uris_from_ids([gid_string], type: Ticket)).to eq([gid])
+    end
+
+    it 'skips item if class is not allowed' do
+      expect(described_class.local_uris_from_ids([gid_string], type: User)).to be_blank
+    end
   end
 end