added ClearEntries function (#2)

README.md

@@ -16,7 +16,7 @@ kb, err := keybase.Open(keybase.WithStorage("/tmp/keybase.db"), keybase.WithTTL(
 ```
 
 This will initialize a database at `/tmp/keybase.db` with a key timeout of one minute. Once
-keybase is open, it is ready to store and maintain keys. Each key is assigned to a nanespace
+keybase is open, it is ready to store and maintain keys. Each key is assigned to a namespace
 and can be inserted using the `Put` function:
 
 ```go

keybase.go

@@ -218,6 +218,17 @@ func (k *Keybase) PruneEntries(ctx context.Context) error {
 	return nil
 }
 
+// ClearEntries removes all entries.
+func (k *Keybase) ClearEntries(ctx context.Context) error {
+	k.mu.Lock()
+	defer k.mu.Unlock()
+	err := newClearEntriesQuery().queryExec(ctx, k.db)
+	if err != nil {
+		return fmt.Errorf("keybase.PruneEntries: failed to insert key: %v", err)
+	}
+	return nil
+}
+
 func sqlOpen(driverName string, dataSourceName string) (*sql.DB, error) {
 	db, _ := sql.Open(driverName, dataSourceName)
 	err := db.Ping()

keybase_test.go

@@ -169,7 +169,7 @@ func TestNamespaces(t *testing.T) {
 	assert.Error(t, err)
 }
 
-// TestEntries tests CountEntries and PruneEntries
+// TestEntries tests CountEntries, PruneEntries, and ClearEntries
 func TestEntries(t *testing.T) {
 	keybase, err := Open(context.TODO(), WithTTL(time.Millisecond*50))
 	assert.NoError(t, err)
@@ -206,12 +206,28 @@ func TestEntries(t *testing.T) {
 	assert.Zero(t, count)
 	assert.NoError(t, err)
 
+	err = keybase.Put(context.TODO(), "namespace", "key")
+	assert.NoError(t, err)
+
+	count, err = keybase.CountEntries(context.TODO(), false, false)
+	assert.Equal(t, 1, count)
+	assert.NoError(t, err)
+
+	err = keybase.ClearEntries(context.TODO())
+	assert.NoError(t, err)
+
+	count, err = keybase.CountEntries(context.TODO(), false, false)
+	assert.Zero(t, count)
+	assert.NoError(t, err)
+
 	ctx, cancel := context.WithTimeout(context.TODO(), time.Duration(0))
 	defer cancel()
 	_, err = keybase.CountEntries(ctx, true, true)
 	assert.Error(t, err)
 	err = keybase.PruneEntries(ctx)
 	assert.Error(t, err)
+	err = keybase.ClearEntries(ctx)
+	assert.Error(t, err)
 }
 
 // TestStorage tests filesystem

query.go

@@ -155,6 +155,12 @@ func newPruneEntriesQuery(timestamp int64) *dbtx {
 	return tx
 }
 
+func newClearEntriesQuery() *dbtx {
+	return &dbtx{
+		query: "DELETE FROM keybase;",
+	}
+}
+
 func (tx dbtx) queryExec(ctx context.Context, db *sql.DB) error {
 	_, err := db.ExecContext(ctx, tx.query, tx.args...)
 	if err != nil {

query_test.go

@@ -184,6 +184,19 @@ func TestNewPruneEntriesQuery(t *testing.T) {
 	assert.NoError(t, err)
 }
 
+func TestNewClearEntriesQuery(t *testing.T) {
+	db, mock := newMock()
+	tx := newClearEntriesQuery()
+
+	mock.ExpectExec(regexp.QuoteMeta(tx.query)).WillReturnError(errors.New("some error"))
+	err := tx.queryExec(context.TODO(), db)
+	assert.Error(t, err)
+
+	mock.ExpectExec(regexp.QuoteMeta(tx.query)).WillReturnResult(sqlmock.NewResult(1, 1))
+	err = tx.queryExec(context.TODO(), db)
+	assert.NoError(t, err)
+}
+
 func TestQueryCount(t *testing.T) {
 	db, mock := newMock()
 	tx := &dbtx{query: ""}