From 20fddcfb4f87e47d9e49eef6ed32cd3c181d6d2b Mon Sep 17 00:00:00 2001
From: nsz <nsz@port70.net>
Date: Wed, 16 Nov 2011 12:14:13 +0100
Subject: [PATCH] simple store implementation

---
 store/store.go | 82 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 82 insertions(+)
 create mode 100644 store/store.go

diff --git a/store/store.go b/store/store.go
new file mode 100644
index 0000000..48614f2
--- /dev/null
+++ b/store/store.go
@@ -0,0 +1,82 @@
+package store
+
+// persistent key-value store
+// TODO: thread safety, persistence, efficient update and query, incremental backup
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"io/ioutil"
+	"sync"
+)
+
+
+type Conn struct {
+	name string
+	path string
+	mutex sync.RWMutex
+	memstore map[string][]byte
+}
+
+func Open(name string) (c *Conn, err error) {
+	c = new(Conn)
+	c.memstore = make(map[string][]byte)
+	c.name = name
+	c.path, err = filepath.Abs(name)
+	if err != nil {
+		return
+	}
+	err = os.MkdirAll(c.path, 0755)
+	if err != nil {
+		return
+	}
+	err = filepath.Walk(c.path, func(path string, info *os.FileInfo, err error) error {
+		if info.IsDirectory() {
+			if info.Name == c.name {
+				return nil
+			}
+			return filepath.SkipDir
+		}
+		if err != nil {
+			return err
+		}
+		k := info.Name
+		v, err := ioutil.ReadFile(filepath.Join(c.path, k))
+		if err != nil {
+			return err
+		}
+		c.memstore[k] = v
+		return nil
+	})
+	return
+}
+
+func (c *Conn) Get(k string) (v []byte, err error) {
+	c.mutex.RLock()
+	defer c.mutex.RUnlock()
+	v, ok := c.memstore[k]
+	if !ok {
+		err = fmt.Errorf("key not found")
+	}
+	return
+}
+
+func (c *Conn) Set(k string, v []byte) (err error) {
+	c.mutex.Lock()
+	defer c.mutex.Unlock()
+	f, err := os.Create(filepath.Join(c.path, k))
+	if err != nil {
+		return
+	}
+	_, err = f.Write(v)
+	if err != nil {
+		return
+	}
+	c.memstore[k] = v
+	return
+}
+
+func (c *Conn) Close() (err error) {
+	return
+}
-- 
2.20.1