riteshghorse commented on code in PR #23450: URL: https://github.com/apache/beam/pull/23450#discussion_r993516764
########## sdks/go/pkg/beam/transforms/xlang/external.go: ########## @@ -0,0 +1,129 @@ +// Licensed to the Apache Software Foundation (ASF) under one or more +// contributor license agreements. See the NOTICE file distributed with +// this work for additional information regarding copyright ownership. +// The ASF licenses this file to You under the Apache License, Version 2.0 +// (the "License"); you may not use this file except in compliance with +// the License. You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// Package xlang contains data structures required for python external transforms in a multilanguage pipeline. +package xlang + +import ( + "fmt" + "io" + "reflect" + + "github.com/apache/beam/sdks/v2/go/pkg/beam" + "github.com/apache/beam/sdks/v2/go/pkg/beam/core/graph/coder" + "github.com/apache/beam/sdks/v2/go/pkg/beam/core/util/reflectx" +) + +const ( + pythonCallableUrn = "beam:logical_type:python_callable:v1" +) + +var ( + pcsType = reflect.TypeOf((*PythonCallableSource)(nil)).Elem() + pcsStorageType = reflectx.String +) + +func init() { + beam.RegisterType(pcsType) + beam.RegisterSchemaProviderWithURN(pcsType, &PythonCallableSourceProvider{}, pythonCallableUrn) +} + +// PythonCallableSource is a wrapper object storing a Python function definition +// that can be evaluated to Python callables in Python SDK. +// +// The snippet of Python code can be a valid Python expression such as +// lambda x: x * x +// str.upper +// a fully qualified name such as +// math.sin +// or a complete multi-line function or class definition such as +// def foo(x): +// ... +// class Foo: +// ... +// +// Any lines preceding the function definition are first evaluated to provide context in which to +// define the function which can be useful to declare imports or any other needed values, e.g. +// import math +// +// def helper(x): +// return x * x +// +// def func(y): +// return helper(y) + y +// in which case `func` would get applied to each element. +type PythonCallableSource string + +// PythonCallableSourceProvider implement the SchemaProvider interface for logical types +type PythonCallableSourceProvider struct{} Review Comment: outdated with above comment -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
