[
https://issues.apache.org/jira/browse/BEAM-14347?focusedWorklogId=768015&page=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-768015
]
ASF GitHub Bot logged work on BEAM-14347:
-----------------------------------------
Author: ASF GitHub Bot
Created on: 09/May/22 16:55
Start Date: 09/May/22 16:55
Worklog Time Spent: 10m
Work Description: lostluck commented on code in PR #17574:
URL: https://github.com/apache/beam/pull/17574#discussion_r868221388
##########
sdks/go/pkg/beam/registration/iter.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 registration
+
+import (
+ "fmt"
+ "io"
+ "reflect"
+
+ "github.com/apache/beam/sdks/v2/go/pkg/beam/core/runtime/exec"
+)
+
+type iter1[T any] struct {
+ s exec.ReStream
+
+ // cur is the "current" stream, if any.
+ cur exec.Stream
+}
+
+func (v *iter1[T]) Init() error {
+ cur, err := v.s.Open()
+ if err != nil {
+ return err
+ }
+ v.cur = cur
+ return nil
+}
+
+func (v *iter1[T]) Value() interface{} {
+ return v.invoke
+}
+
+func (v *iter1[T]) Reset() error {
+ if err := v.cur.Close(); err != nil {
+ return err
+ }
+ v.cur = nil
+ return nil
+}
+
+func (v *iter1[T]) invoke(value *T) bool {
+ elm, err := v.cur.Read()
+ if err != nil {
+ if err == io.EOF {
+ return false
+ }
+ panic(fmt.Sprintf("broken stream: %v", err))
+ }
+ *value = elm.Elm.(T)
+ return true
+}
+
+type iter2[T1, T2 any] struct {
+ s exec.ReStream
+
+ // cur is the "current" stream, if any.
+ cur exec.Stream
+}
+
+func (v *iter2[T1, T2]) Init() error {
+ cur, err := v.s.Open()
+ if err != nil {
+ return err
+ }
+ v.cur = cur
+ return nil
+}
+
+func (v *iter2[T1, T2]) Value() interface{} {
+ return v.invoke
+}
+
+func (v *iter2[T1, T2]) Reset() error {
+ if err := v.cur.Close(); err != nil {
+ return err
+ }
+ v.cur = nil
+ return nil
+}
+
+func (v *iter2[T1, T2]) invoke(key *T1, value *T2) bool {
+ elm, err := v.cur.Read()
+ if err != nil {
+ if err == io.EOF {
+ return false
+ }
+ panic(fmt.Sprintf("broken stream: %v", err))
+ }
+ *key = elm.Elm.(T1)
+ *value = elm.Elm2.(T2)
+ return true
+}
+
+// Iter1 registers parameters from your DoFn with a
+// signature func(*T) bool and optimizes their execution.
+// This must be done by passing in type parameters of all inputs as
constraints,
+// aka: registration.Iter1[T]()
Review Comment:
The input parameter must be a pointer so what you had as *T is correct, but
T itself could be a pointer type like `*Foo`, so the resolved iterator would be
`func(**Foo) bool`
Issue Time Tracking
-------------------
Worklog Id: (was: 768015)
Time Spent: 10h 20m (was: 10h 10m)
> [Go SDK] Allow users to optimize DoFns with a single generic registration
> function
> ----------------------------------------------------------------------------------
>
> Key: BEAM-14347
> URL: https://issues.apache.org/jira/browse/BEAM-14347
> Project: Beam
> Issue Type: New Feature
> Components: sdk-go
> Reporter: Danny McCormick
> Assignee: Danny McCormick
> Priority: P2
> Time Spent: 10h 20m
> Remaining Estimate: 0h
>
> Right now, to optimize DoFn execution, users have to use the code generator.
> This updates to allow them to use generics instead.
--
This message was sent by Atlassian Jira
(v8.20.7#820007)
