Testcase for FoundationDB Go binding issue 11621

repro11621.go

package main

import (
	"fmt"
	"os"
	"time"

	"github.com/apple/foundationdb/bindings/go/src/fdb"
)

func main() {
	const useMultiVersion = true

	err := setup(useMultiVersion)
	if err != nil {
		panic(err)
	}

	for _, d := range []time.Duration{0, time.Millisecond * 50} {
		err := runTestcase("/fdb/cluster-file", useMultiVersion, d)
		if err != nil {
			panic(err)
		}
	}
}

func setup(useMultiVersion bool) error {
	err := fdb.APIVersion(730)
	if err != nil {
		return err
	}

	v, err := fdb.GetAPIVersion()
	if err != nil {
		return err
	}
	if v != 730 {
		return fmt.Errorf("unexpected API version: %v", v)
	}

	if useMultiVersion {
		if err := fdb.Options().SetExternalClientDirectory("/usr/lib/multiversion-fdb"); err != nil {
			return fmt.Errorf("failed to enable multiversion client: %w", err)
		}
	}

	return nil
}

func runTestcase(clusterFile string, useMultiVersion bool, initialDelay time.Duration) error {
	db, err := fdb.OpenDatabase(clusterFile)
	if err != nil {
		b, _ := os.ReadFile(clusterFile)
		return fmt.Errorf("failed to initialize FDB with cluster file %v (content: %q): %w", clusterFile, string(b), err)
	}

	var emptyD time.Duration
	if initialDelay != emptyD {
		fmt.Printf("initial delay of %.2f seconds\n", initialDelay.Seconds())
		time.Sleep(initialDelay)
	} else {
		fmt.Printf("no initial delay\n")
	}

	var f fdb.FutureInt64
	_, err = db.ReadTransact(func(rt fdb.ReadTransaction) (interface{}, error) {
		f = rt.GetReadVersion()
		return nil, nil
	})
	if err != nil {
		fmt.Printf("initial empty R/O tx: %v (using multiversion client = %v)\n", err, useMultiVersion)
	} else {
		rv, err := f.Get()
		if err != nil {
			fmt.Printf("initial empty R/O tx, failed to get future: %v (using multiversion client = %v)\n", err, useMultiVersion)
		} else {
			fmt.Printf("initial empty R/O tx: got read version %v (using multiversion client = %v)\n", rv, useMultiVersion)
		}
	}

	// second tx always works
	_, err = db.ReadTransact(func(rt fdb.ReadTransaction) (interface{}, error) {
		f = rt.GetReadVersion()
		return nil, nil
	})
	if err != nil {
		return err
	}

	rv, err := f.Get()
	if err != nil {
		return err
	}
	fmt.Printf("second empty R/O tx: got read version %v (using multiversion client = %v)\n", rv, useMultiVersion)

	return nil
}