[apache#24789][prism] Add testdofns for later (apache#25557)

* [prism] Add testdofns for later

* [prism] typo comments

sdks/go/pkg/beam/runners/prism/internal/testdofns.go

@@ -0,0 +1,349 @@
+// 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 internal
+
+import (
+	"context"
+	"fmt"
+	"sort"
+	"time"
+
+	"github.com/apache/beam/sdks/v2/go/pkg/beam"
+	"github.com/apache/beam/sdks/v2/go/pkg/beam/core/sdf"
+	"github.com/apache/beam/sdks/v2/go/pkg/beam/io/rtrackers/offsetrange"
+	"github.com/apache/beam/sdks/v2/go/pkg/beam/log"
+	"github.com/apache/beam/sdks/v2/go/pkg/beam/register"
+	"github.com/google/go-cmp/cmp"
+)
+
+// The Test DoFns live outside of the test files to get coverage information on DoFn
+// Lifecycle method execution. This inflates binary size, but ensures the runner is
+// exercising the expected feature set.
+//
+// Once there's enough confidence in the runner, we can move these into a dedicated testing
+// package along with the pipelines that use them.
+
+// Registrations should happen in the test files, so the compiler can prune these
+// when they are not in use.
+
+func dofn1(imp []byte, emit func(int64)) {
+	emit(1)
+	emit(2)
+	emit(3)
+}
+
+func dofn1kv(imp []byte, emit func(int64, int64)) {
+	emit(0, 1)
+	emit(0, 2)
+	emit(0, 3)
+}
+
+func dofn1x2(imp []byte, emitA func(int64), emitB func(int64)) {
+	emitA(1)
+	emitA(2)
+	emitA(3)
+	emitB(4)
+	emitB(5)
+	emitB(6)
+}
+
+func dofn1x5(imp []byte, emitA, emitB, emitC, emitD, emitE func(int64)) {
+	emitA(1)
+	emitB(2)
+	emitC(3)
+	emitD(4)
+	emitE(5)
+	emitA(6)
+	emitB(7)
+	emitC(8)
+	emitD(9)
+	emitE(10)
+}
+
+func dofn2x1(imp []byte, iter func(*int64) bool, emit func(int64)) {
+	var v, sum, c int64
+	for iter(&v) {
+		fmt.Println("dofn2x1 v", v, " c ", c)
+		sum += v
+		c++
+	}
+	fmt.Println("dofn2x1 sum", sum, "count", c)
+	emit(sum)
+}
+
+func dofn2x2KV(imp []byte, iter func(*string, *int64) bool, emitK func(string), emitV func(int64)) {
+	var k string
+	var v, sum int64
+	for iter(&k, &v) {
+		sum += v
+		emitK(k)
+	}
+	emitV(sum)
+}
+
+func dofnMultiMap(key string, lookup func(string) func(*int64) bool, emitK func(string), emitV func(int64)) {
+	var v, sum int64
+	iter := lookup(key)
+	for iter(&v) {
+		sum += v
+	}
+	emitK(key)
+	emitV(sum)
+}
+
+func dofn3x1(sum int64, iter1, iter2 func(*int64) bool, emit func(int64)) {
+	var v int64
+	for iter1(&v) {
+		sum += v
+	}
+	for iter2(&v) {
+		sum += v
+	}
+	emit(sum)
+}
+
+// int64Check validates that within a single bundle,
+// we received the expected int64 values & sends them downstream.
+//
+// Invalid pattern for general testing, as it will fail
+// on other valid execution patterns, like single element bundles.
+type int64Check struct {
+	Name string
+	Want []int
+	got  []int
+}
+
+func (fn *int64Check) ProcessElement(v int64, _ func(int64)) {
+	fn.got = append(fn.got, int(v))
+}
+
+func (fn *int64Check) FinishBundle(_ func(int64)) error {
+	sort.Ints(fn.got)
+	sort.Ints(fn.Want)
+	if d := cmp.Diff(fn.Want, fn.got); d != "" {
+		return fmt.Errorf("int64Check[%v] (-want, +got): %v", fn.Name, d)
+	}
+	// Clear for subsequent calls.
+	fn.got = nil
+	return nil
+}
+
+// stringCheck validates that within a single bundle,
+// we received the expected string values.
+// Re-emits them downstream.
+//
+// Invalid pattern for general testing, as it will fail
+// on other valid execution patterns, like single element bundles.
+type stringCheck struct {
+	Name string
+	Want []string
+	got  []string
+}
+
+func (fn *stringCheck) ProcessElement(v string, _ func(string)) {
+	fn.got = append(fn.got, v)
+}
+
+func (fn *stringCheck) FinishBundle(_ func(string)) error {
+	sort.Strings(fn.got)
+	sort.Strings(fn.Want)
+	if d := cmp.Diff(fn.Want, fn.got); d != "" {
+		return fmt.Errorf("stringCheck[%v] (-want, +got): %v", fn.Name, d)
+	}
+	return nil
+}
+
+func dofn2(v int64, emit func(int64)) {
+	emit(v + 1)
+}
+
+func dofnKV(imp []byte, emit func(string, int64)) {
+	emit("a", 1)
+	emit("b", 2)
+	emit("a", 3)
+	emit("b", 4)
+	emit("a", 5)
+	emit("b", 6)
+}
+
+func dofnKV2(imp []byte, emit func(int64, string)) {
+	emit(1, "a")
+	emit(2, "b")
+	emit(1, "a")
+	emit(2, "b")
+	emit(1, "a")
+	emit(2, "b")
+}
+
+func dofnGBK(k string, vs func(*int64) bool, emit func(int64)) {
+	var v, sum int64
+	for vs(&v) {
+		sum += v
+	}
+	emit(sum)
+}
+
+func dofnGBK2(k int64, vs func(*string) bool, emit func(string)) {
+	var v, sum string
+	for vs(&v) {
+		sum += v
+	}
+	emit(sum)
+}
+
+type testRow struct {
+	A string
+	B int64
+}
+
+func dofnKV3(imp []byte, emit func(testRow, testRow)) {
+	emit(testRow{"a", 1}, testRow{"a", 1})
+}
+
+func dofnGBK3(k testRow, vs func(*testRow) bool, emit func(string)) {
+	var v testRow
+	vs(&v)
+	emit(fmt.Sprintf("%v: %v", k, v))
+}
+
+const (
+	ns = "localtest"
+)
+
+func dofnSink(ctx context.Context, _ []byte) {
+	beam.NewCounter(ns, "sunk").Inc(ctx, 73)
+}
+
+func dofn1Counter(ctx context.Context, _ []byte, emit func(int64)) {
+	beam.NewCounter(ns, "count").Inc(ctx, 1)
+}
+
+func combineIntSum(a, b int64) int64 {
+	return a + b
+}
+
+// SourceConfig is a struct containing all the configuration options for a
+// synthetic source. It should be created via a SourceConfigBuilder, not by
+// directly initializing it (the fields are public to allow encoding).
+type SourceConfig struct {
+	NumElements   int64 `json:"num_records" beam:"num_records"`
+	InitialSplits int64 `json:"initial_splits" beam:"initial_splits"`
+}
+
+// intRangeFn is a splittable DoFn for counting from 1 to N.
+type intRangeFn struct{}
+
+// CreateInitialRestriction creates an offset range restriction representing
+// the number of elements to emit.
+func (fn *intRangeFn) CreateInitialRestriction(config SourceConfig) offsetrange.Restriction {
+	return offsetrange.Restriction{
+		Start: 0,
+		End:   int64(config.NumElements),
+	}
+}
+
+// SplitRestriction splits restrictions equally according to the number of
+// initial splits specified in SourceConfig. Each restriction output by this
+// method will contain at least one element, so the number of splits will not
+// exceed the number of elements.
+func (fn *intRangeFn) SplitRestriction(config SourceConfig, rest offsetrange.Restriction) (splits []offsetrange.Restriction) {
+	return rest.EvenSplits(int64(config.InitialSplits))
+}
+
+// RestrictionSize outputs the size of the restriction as the number of elements
+// that restriction will output.
+func (fn *intRangeFn) RestrictionSize(_ SourceConfig, rest offsetrange.Restriction) float64 {
+	return rest.Size()
+}
+
+// CreateTracker just creates an offset range restriction tracker for the
+// restriction.
+func (fn *intRangeFn) CreateTracker(rest offsetrange.Restriction) *sdf.LockRTracker {
+	return sdf.NewLockRTracker(offsetrange.NewTracker(rest))
+}
+
+// ProcessElement creates a number of random elements based on the restriction
+// tracker received. Each element is a random byte slice key and value, in the
+// form of KV<[]byte, []byte>.
+func (fn *intRangeFn) ProcessElement(rt *sdf.LockRTracker, config SourceConfig, emit func(int64)) error {
+	for i := rt.GetRestriction().(offsetrange.Restriction).Start; rt.TryClaim(i); i++ {
+		// Add 1 since the restrictions are from [0 ,N), but we want [1, N]
+		emit(i + 1)
+	}
+	return nil
+}
+
+func init() {
+	register.DoFn3x1[*sdf.LockRTracker, []byte, func(int64), sdf.ProcessContinuation](&selfCheckpointingDoFn{})
+	register.Emitter1[int64]()
+}
+
+type selfCheckpointingDoFn struct{}
+
+// CreateInitialRestriction creates the restriction being used by the SDF. In this case, the range
+// of values produced by the restriction is [Start, End).
+func (fn *selfCheckpointingDoFn) CreateInitialRestriction(_ []byte) offsetrange.Restriction {
+	return offsetrange.Restriction{
+		Start: int64(0),
+		End:   int64(10),
+	}
+}
+
+// CreateTracker wraps the given restriction into a LockRTracker type.
+func (fn *selfCheckpointingDoFn) CreateTracker(rest offsetrange.Restriction) *sdf.LockRTracker {
+	return sdf.NewLockRTracker(offsetrange.NewTracker(rest))
+}
+
+// RestrictionSize returns the size of the current restriction
+func (fn *selfCheckpointingDoFn) RestrictionSize(_ []byte, rest offsetrange.Restriction) float64 {
+	return rest.Size()
+}
+
+// SplitRestriction modifies the offsetrange.Restriction's sized restriction function to produce a size-zero restriction
+// at the end of execution.
+func (fn *selfCheckpointingDoFn) SplitRestriction(_ []byte, rest offsetrange.Restriction) []offsetrange.Restriction {
+	size := int64(3)
+	s := rest.Start
+	var splits []offsetrange.Restriction
+	for e := s + size; e <= rest.End; s, e = e, e+size {
+		splits = append(splits, offsetrange.Restriction{Start: s, End: e})
+	}
+	splits = append(splits, offsetrange.Restriction{Start: s, End: rest.End})
+	return splits
+}
+
+// ProcessElement continually gets the start position of the restriction and emits it as an int64 value before checkpointing.
+// This causes the restriction to be split after the claimed work and produce no primary roots.
+func (fn *selfCheckpointingDoFn) ProcessElement(rt *sdf.LockRTracker, _ []byte, emit func(int64)) sdf.ProcessContinuation {
+	position := rt.GetRestriction().(offsetrange.Restriction).Start
+
+	for {
+		if rt.TryClaim(position) {
+			// Successful claim, emit the value and move on.
+			emit(position)
+			position++
+		} else if rt.GetError() != nil || rt.IsDone() {
+			// Stop processing on error or completion
+			if err := rt.GetError(); err != nil {
+				log.Errorf(context.Background(), "error in restriction tracker, got %v", err)
+			}
+			return sdf.StopProcessing()
+		} else {
+			// Resume later.
+			return sdf.ResumeProcessingIn(5 * time.Second)
+		}
+	}
+}