feat!: Cache GraphQL attributes (#867)

instrumentation/graphql/lib/opentelemetry/instrumentation/graphql/tracers/graphql_tracer.rb

@@ -13,6 +13,8 @@ module Tracers
         # GraphQLTracer contains the OpenTelemetry tracer implementation compatible with
         # the GraphQL tracer API
         class GraphQLTracer < ::GraphQL::Tracing::PlatformTracing
+          DEFAULT_HASH = {}.freeze
+
           self.platform_keys = {
             'lex' => 'graphql.lex',
             'parse' => 'graphql.parse',
@@ -86,24 +88,60 @@ def config
           end
 
           def attributes_for(key, data)
-            attributes = {}
             case key
-            when 'execute_field', 'execute_field_lazy'
-              attributes['graphql.field.parent'] = data[:owner]&.graphql_name # owner is the concrete type, not interface
-              attributes['graphql.field.name'] = data[:field]&.graphql_name
-              attributes['graphql.lazy'] = key == 'execute_field_lazy'
-            when 'authorized', 'authorized_lazy'
-              attributes['graphql.type.name'] = data[:type]&.graphql_name
-              attributes['graphql.lazy'] = key == 'authorized_lazy'
-            when 'resolve_type', 'resolve_type_lazy'
-              attributes['graphql.type.name'] = data[:type]&.graphql_name
-              attributes['graphql.lazy'] = key == 'resolve_type_lazy'
+            when 'execute_field'
+              field_attr_cache = data[:query].context.namespace(:otel_attrs)[:execute_field_attrs] ||= attr_cache do |field|
+                attrs = {}
+                attrs['graphql.field.parent'] = field.owner.graphql_name if field.owner.graphql_name
+                attrs['graphql.field.name'] = field.graphql_name if field.graphql_name
+                attrs['graphql.lazy'] = false
+                attrs.freeze
+              end
+              field_attr_cache[data[:field]]
+            when 'execute_field_lazy'
+              lazy_field_attr_cache = data[:query].context.namespace(:otel_attrs)[:execute_field_lazy_attrs] ||= attr_cache do |field|
+                attrs = {}
+                attrs['graphql.field.parent'] = field.owner.graphql_name if field.owner.graphql_name
+                attrs['graphql.field.name'] = field.graphql_name if field.graphql_name
+                attrs['graphql.lazy'] = true
+                attrs.freeze
+              end
+              lazy_field_attr_cache[data[:field]]
+            when 'authorized', 'resolve_type'
+              type_attrs_cache = data[:context].namespace(:otel_attrs)[:type_attrs] ||= attr_cache do |type|
+                attrs = {}
+                attrs['graphql.type.name'] = type.graphql_name if type.graphql_name
+                attrs['graphql.lazy'] = false
+                attrs.freeze
+              end
+              type_attrs_cache[data[:type]]
+            when 'authorized_lazy', 'resolve_type_lazy'
+              type_lazy_attrs_cache = data[:context].namespace(:otel_attrs)[:type_lazy_attrs] ||= attr_cache do |type|
+                attrs = {}
+                attrs['graphql.type.name'] = type.graphql_name if type.graphql_name
+                attrs['graphql.lazy'] = true
+                attrs.freeze
+              end
+              type_lazy_attrs_cache[data[:type]]
             when 'execute_query'
-              attributes['graphql.operation.name'] = data[:query].selected_operation_name if data[:query].selected_operation_name
-              attributes['graphql.operation.type'] = data[:query].selected_operation.operation_type
-              attributes['graphql.document'] = data[:query].query_string
+              attrs = {}
+              attrs['graphql.document'] = data[:query].query_string if data[:query].query_string
+              # rubocop:disable Style/SafeNavigation - using safe navigation creates more objects, we want to avoid this
+              attrs['graphql.operation.type'] = data[:query].selected_operation.operation_type if data[:query].selected_operation && data[:query].selected_operation.operation_type
+              # rubocop:enable Style/SafeNavigation
+              attrs['graphql.operation.name'] = data[:query].selected_operation_name || 'anonymous'
+              attrs.freeze
+            else
+              DEFAULT_HASH
+            end
+          end
+
+          def attr_cache
+            cache_h = Hash.new do |h, k|
+              h[k] = yield(k)
             end
-            attributes
+            cache_h.compare_by_identity
+            cache_h
           end
         end
       end

instrumentation/graphql/test/instrumentation/graphql/tracers/graphql_tracer_test.rb

@@ -83,7 +83,8 @@
       it 'omits nil attributes for execute_query' do
         expected_attributes = {
           'graphql.operation.type' => 'query',
-          'graphql.document' => '{ simpleField }'
+          'graphql.document' => '{ simpleField }',
+          'graphql.operation.name' => 'anonymous'
         }
 
         SomeGraphQLAppSchema.execute('{ simpleField }')
@@ -141,7 +142,7 @@
         it 'includes attributes using platform types' do
           skip if uses_platform_interfaces?
           expected_attributes = {
-            'graphql.field.parent' => 'Car', # type name, not interface
+            'graphql.field.parent' => 'Vehicle', # interface name, not type
             'graphql.field.name' => 'model',
             'graphql.lazy' => false
           }