Fix auto create db dir (#123)

* 1. adding util existing check func

* 2. make bbolt.Open() auto create db dir if not exist

* 3. adding test for that

* 4. modify example for it

db_test.go

@@ -410,6 +410,9 @@ func TestOpenExisting(t *testing.T) {
 	defer os.RemoveAll(dir)
 	require.NoError(t, err)
 
+	err = os.RemoveAll(dir)
+	require.NoError(t, err)
+
 	db, err := c.Open(dir)
 	require.NoError(t, err)
 

examples/collections/main.go

@@ -3,11 +3,13 @@ package main
 import (
 	"fmt"
 	"log"
+	"os"
 
 	c "github.com/ostafen/clover/v2"
 )
 
 func main() {
+	_ = os.RemoveAll("clover-db")
 	db, err := c.Open("clover-db")
 	if err != nil {
 		log.Panicf("Failed to open db: %v", err)

store/bbolt/bbolt.go

@@ -2,9 +2,11 @@ package bbolt
 
 import (
 	"bytes"
+	"os"
 	"path/filepath"
 
 	"github.com/ostafen/clover/v2/store"
+	"github.com/ostafen/clover/v2/util"
 	"go.etcd.io/bbolt"
 )
 
@@ -18,6 +20,16 @@ const (
 )
 
 func Open(dir string) (store.Store, error) {
+	dirExists, err := util.PathExists(dir)
+	if err != nil {
+		return nil, err
+	}
+	if !dirExists {
+		err = os.MkdirAll(dir, 0700)
+		if err != nil {
+			return nil, err
+		}
+	}
 	db, err := bbolt.Open(filepath.Join(dir, dbFileName), 0600, nil)
 	if err != nil {
 		return nil, err

util/fs.go

@@ -0,0 +1,14 @@
+package util
+
+import "os"
+
+func PathExists(path string) (bool, error) {
+	_, err := os.Stat(path)
+	if err == nil {
+		return true, nil
+	}
+	if os.IsNotExist(err) {
+		return false, nil
+	}
+	return true, err
+}