A test for GCReclaim

clovertest.go

package main

import (
	"fmt"
	"log"
	"math/rand"
	"time"

	"github.com/ostafen/clover/v2"
)

var letterRunes = []rune("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789")

func checkErr(err error) {
	if err != nil {
		log.Fatal(err)
	}
}

func main() {
	db, err := clover.Open("./db", clover.WithGCReclaimInterval(time.Second*5))
	checkErr(err)
	defer db.Close()

	has, err := db.HasCollection("test")
	checkErr(err)
	if !has {
		checkErr(db.CreateCollection("test"))
		// checkErr(db.CreateIndex("test", "timestamp"))
	}

	// create a 10,000 byte string
	str := RandStringRunes(10000)

	log.Println("Inserting 100,000 documents")
	for i := 0; i < 100000; i++ {
		if i > 0 && i%1000 == 0 {
			log.Printf("Inserted %d documents", i)
		}

		doc := clover.NewDocument()
		doc.Set("timestamp", time.Now().UnixNano())
		doc.Set("Data", str)
		_, err := db.InsertOne("test", doc)
		checkErr(err)
	}

	printDocumentsInDB(db)

	fmt.Println("Deleting 100,000 documents")

	deleteAll(db)

	printDocumentsInDB(db)

	for i := 0; i < 10; i++ {
		n := 1000
		log.Printf("Inserting %d documents", n)
		for i := 0; i < n; i++ {
			doc := clover.NewDocument()
			doc.Set("timestamp", time.Now().UnixNano())
			doc.Set("Data", str)
			_, err := db.InsertOne("test", doc)
			checkErr(err)
		}

		printDocumentsInDB(db)
		log.Printf("Deleting %d documents", n)
		deleteAll(db)
		printDocumentsInDB(db)
	}

	log.Println("Pause an extra 30 seconds to show GC isn't cleaning up an empty database effectively")
	time.Sleep(30 * time.Second)
}

func deleteAll(db *clover.DB) {
	for {
		toDelete, err := db.Count(clover.NewQuery("test"))
		checkErr(err)
		if toDelete == 0 {
			break
		}
		checkErr(db.Delete(clover.NewQuery("test").Limit(2500)))
	}

	// makes no difference if I delete documents or drop/create the collection
	// checkErr(db.DropCollection("test"))
	// checkErr(db.CreateCollection("test"))
}

// print totals
func printDocumentsInDB(db *clover.DB) {
	n, err := db.Count(clover.NewQuery("test"))
	checkErr(err)
	log.Printf("There are now %d documents in DB", n)
}

// RandStringRunes generates a random string
func RandStringRunes(n int) string {
	b := make([]rune, n)
	for i := range b {
		b[i] = letterRunes[rand.Intn(len(letterRunes))]
	}
	return string(b)
}