Fix GC deleting values without expiry (#54)

* Test MYSQL Fix

* Test

* Add postgres

* Fix mysql

* Fix sqlite

mysql/mysql.go

@@ -82,11 +82,11 @@ func New(config ...Config) *Storage {
 		sqlInsert:  fmt.Sprintf("INSERT INTO %s (k, v, e) VALUES (?,?,?) ON DUPLICATE KEY UPDATE v = ?, e = ?", cfg.Table),
 		sqlDelete:  fmt.Sprintf("DELETE FROM %s WHERE k=?", cfg.Table),
 		sqlReset:   fmt.Sprintf("DELETE FROM %s;", cfg.Table),
-		sqlGC:      fmt.Sprintf("DELETE FROM %s WHERE e <= ?", cfg.Table),
+		sqlGC:      fmt.Sprintf("DELETE FROM %s WHERE e <= ? AND e != 0", cfg.Table),
 	}
 
 	// Start garbage collector
-	go store.gc()
+	go store.gcTicker()
 
 	return store
 }
@@ -160,8 +160,8 @@ func (s *Storage) Close() error {
 	return s.db.Close()
 }
 
-// Garbage collector to delete expired keys
+// gcTicker starts the gc ticker
-func (s *Storage) gc() {
+func (s *Storage) gcTicker() {
 	ticker := time.NewTicker(s.gcInterval)
 	defer ticker.Stop()
 	for {
@@ -169,7 +169,12 @@ func (s *Storage) gc() {
 		case <-s.done:
 			return
 		case t := <-ticker.C:
-			_, _ = s.db.Exec(s.sqlGC, t.Unix())
+			s.gc(t)
 		}
 	}
 }
+
+// gc deletes all expired entries
+func (s *Storage) gc(t time.Time) {
+	_, _ = s.db.Exec(s.sqlGC, t.Unix())
+}

mysql/mysql_test.go

@@ -1,6 +1,7 @@
 package mysql
 
 import (
+	"database/sql"
 	"os"
 	"testing"
 	"time"
@@ -122,6 +123,31 @@ func Test_MYSQL_Reset(t *testing.T) {
 	utils.AssertEqual(t, true, len(result) == 0)
 }
 
+func Test_MYSQL_GC(t *testing.T) {
+	var (
+		testVal = []byte("doe")
+	)
+
+	// This key should expire
+	err := testStore.Set("john", testVal, time.Nanosecond)
+	utils.AssertEqual(t, nil, err)
+
+	testStore.gc(time.Now())
+	row := testStore.db.QueryRow(testStore.sqlSelect, "john")
+	err = row.Scan(nil, nil)
+	utils.AssertEqual(t, sql.ErrNoRows, err)
+
+	// This key should not expire
+	err = testStore.Set("john", testVal, 0)
+	utils.AssertEqual(t, nil, err)
+
+	testStore.gc(time.Now())
+	val, err := testStore.Get("john")
+	utils.AssertEqual(t, nil, err)
+	utils.AssertEqual(t, testVal, val)
+
+}
+
 func Test_MYSQL_Close(t *testing.T) {
 	utils.AssertEqual(t, nil, testStore.Close())
 }

postgres/postgres.go

@@ -100,11 +100,11 @@ func New(config ...Config) *Storage {
 		sqlInsert:  fmt.Sprintf("INSERT INTO %s (k, v, e) VALUES ($1, $2, $3) ON CONFLICT (k) DO UPDATE SET v = $4, e = $5", cfg.Table),
 		sqlDelete:  fmt.Sprintf("DELETE FROM %s WHERE k=$1", cfg.Table),
 		sqlReset:   fmt.Sprintf("DELETE FROM %s;", cfg.Table),
-		sqlGC:      fmt.Sprintf("DELETE FROM %s WHERE e <= $1", cfg.Table),
+		sqlGC:      fmt.Sprintf("DELETE FROM %s WHERE e <= $1 AND e != 0", cfg.Table),
 	}
 
 	// Start garbage collector
-	go store.gc()
+	go store.gcTicker()
 
 	return store
 }
@@ -175,8 +175,8 @@ func (s *Storage) Close() error {
 	return s.db.Close()
 }
 
-// GC deletes all expired entries
+// gcTicker starts the gc ticker
-func (s *Storage) gc() {
+func (s *Storage) gcTicker() {
 	ticker := time.NewTicker(s.gcInterval)
 	defer ticker.Stop()
 	for {
@@ -184,7 +184,12 @@ func (s *Storage) gc() {
 		case <-s.done:
 			return
 		case t := <-ticker.C:
-			_, _ = s.db.Exec(s.sqlGC, t.Unix())
+			s.gc(t)
 		}
 	}
 }
+
+// gc deletes all expired entries
+func (s *Storage) gc(t time.Time) {
+	_, _ = s.db.Exec(s.sqlGC, t.Unix())
+}

postgres/postgres_test.go

@@ -1,6 +1,7 @@
 package postgres
 
 import (
+	"database/sql"
 	"os"
 	"testing"
 	"time"
@@ -122,6 +123,31 @@ func Test_Postgres_Reset(t *testing.T) {
 	utils.AssertEqual(t, true, len(result) == 0)
 }
 
+func Test_Postgres_GC(t *testing.T) {
+	var (
+		testVal = []byte("doe")
+	)
+
+	// This key should expire
+	err := testStore.Set("john", testVal, time.Nanosecond)
+	utils.AssertEqual(t, nil, err)
+
+	testStore.gc(time.Now())
+	row := testStore.db.QueryRow(testStore.sqlSelect, "john")
+	err = row.Scan(nil, nil)
+	utils.AssertEqual(t, sql.ErrNoRows, err)
+
+	// This key should not expire
+	err = testStore.Set("john", testVal, 0)
+	utils.AssertEqual(t, nil, err)
+
+	testStore.gc(time.Now())
+	val, err := testStore.Get("john")
+	utils.AssertEqual(t, nil, err)
+	utils.AssertEqual(t, testVal, val)
+
+}
+
 func Test_Postgres_Close(t *testing.T) {
 	utils.AssertEqual(t, nil, testStore.Close())
 }

sqlite3/sqlite3.go

@@ -81,11 +81,11 @@ func New(config ...Config) *Storage {
 		sqlInsert:  fmt.Sprintf("INSERT OR REPLACE INTO %s (k, v, e) VALUES (?,?,?)", cfg.Table),
 		sqlDelete:  fmt.Sprintf("DELETE FROM %s WHERE k=?", cfg.Table),
 		sqlReset:   fmt.Sprintf("DELETE FROM %s;", cfg.Table),
-		sqlGC:      fmt.Sprintf("DELETE FROM %s WHERE e <= ?", cfg.Table),
+		sqlGC:      fmt.Sprintf("DELETE FROM %s WHERE e <= ? AND e != 0", cfg.Table),
 	}
 
 	// Start garbage collector
-	go store.gc()
+	go store.gcTicker()
 
 	return store
 }
@@ -152,8 +152,8 @@ func (s *Storage) Close() error {
 	return s.db.Close()
 }
 
-// GC deletes all expired entries
+// gcTicker starts the gc ticker
-func (s *Storage) gc() {
+func (s *Storage) gcTicker() {
 	ticker := time.NewTicker(s.gcInterval)
 	defer ticker.Stop()
 	for {
@@ -161,7 +161,12 @@ func (s *Storage) gc() {
 		case <-s.done:
 			return
 		case t := <-ticker.C:
-			_, _ = s.db.Exec(s.sqlGC, t.Unix())
+			s.gc(t)
 		}
 	}
 }
+
+// gc deletes all expired entries
+func (s *Storage) gc(t time.Time) {
+	_, _ = s.db.Exec(s.sqlGC, t.Unix())
+}

sqlite3/sqlite3_test.go

@@ -1,6 +1,7 @@
 package sqlite3
 
 import (
+	"database/sql"
 	"testing"
 	"time"
 
@@ -119,6 +120,31 @@ func Test_SQLite3_Reset(t *testing.T) {
 	utils.AssertEqual(t, true, len(result) == 0)
 }
 
+func Test_SQLite3_GC(t *testing.T) {
+	var (
+		testVal = []byte("doe")
+	)
+
+	// This key should expire
+	err := testStore.Set("john", testVal, time.Nanosecond)
+	utils.AssertEqual(t, nil, err)
+
+	testStore.gc(time.Now())
+	row := testStore.db.QueryRow(testStore.sqlSelect, "john")
+	err = row.Scan(nil, nil)
+	utils.AssertEqual(t, sql.ErrNoRows, err)
+
+	// This key should not expire
+	err = testStore.Set("john", testVal, 0)
+	utils.AssertEqual(t, nil, err)
+
+	testStore.gc(time.Now())
+	val, err := testStore.Get("john")
+	utils.AssertEqual(t, nil, err)
+	utils.AssertEqual(t, testVal, val)
+
+}
+
 func Test_SQLite3_Close(t *testing.T) {
 	utils.AssertEqual(t, nil, testStore.Close())
 }