Add 'bolt get'.

cmd/bolt/main.go

@@ -0,0 +1,115 @@
+package main
+
+import (
+	"bytes"
+	"log"
+	"os"
+
+	"github.com/boltdb/bolt"
+	"github.com/codegangsta/cli"
+)
+
+func main() {
+	log.SetFlags(0)
+	NewApp().Run(os.Args)
+}
+
+// NewApp creates an Application instance.
+func NewApp() *cli.App {
+	app := cli.NewApp()
+	app.Name = "bolt"
+	app.Usage = "BoltDB toolkit"
+	app.Commands = []cli.Command{
+		{
+			Name:   "get",
+			Usage:  "retrieve a value for given key",
+			Action: Get,
+		},
+	}
+	return app
+}
+
+// Get retrieves the value for a given bucket/key.
+func Get(c *cli.Context) {
+	path, name, key := c.Args().Get(0), c.Args().Get(1), c.Args().Get(2)
+	if _, err := os.Stat(path); os.IsNotExist(err) {
+		fatal(err)
+		return
+	}
+
+	db, err := bolt.Open(path, 0600)
+	if err != nil {
+		fatal(err)
+		return
+	}
+	defer db.Close()
+
+	err = db.With(func(tx *bolt.Tx) error {
+		// Find bucket.
+		b := tx.Bucket(name)
+		if b == nil {
+			fatalf("bucket not found: %s", name)
+			return nil
+		}
+
+		// Find value for a given key.
+		value := b.Get([]byte(key))
+		if value == nil {
+			fatalf("key not found: %s", key)
+			return nil
+		}
+
+		logger.Println(string(value))
+		return nil
+	})
+	if err != nil {
+		fatal(err)
+		return
+	}
+}
+
+var logger = log.New(os.Stderr, "", 0)
+var logBuffer *bytes.Buffer
+
+func fatal(v ...interface{}) {
+	logger.Print(v...)
+	if !testMode {
+		os.Exit(1)
+	}
+}
+
+func fatalf(format string, v ...interface{}) {
+	logger.Printf(format, v...)
+	if !testMode {
+		os.Exit(1)
+	}
+}
+
+func fatalln(v ...interface{}) {
+	logger.Println(v...)
+	if !testMode {
+		os.Exit(1)
+	}
+}
+
+// LogBuffer returns the contents of the log.
+// This only works while the CLI is in test mode.
+func LogBuffer() string {
+	if logBuffer != nil {
+		return logBuffer.String()
+	}
+	return ""
+}
+
+var testMode bool
+
+// SetTestMode sets whether the CLI is running in test mode and resets the logger.
+func SetTestMode(value bool) {
+	testMode = value
+	if testMode {
+		logBuffer = bytes.NewBuffer(nil)
+		logger = log.New(logBuffer, "", 0)
+	} else {
+		logger = log.New(os.Stderr, "", 0)
+	}
+}

cmd/bolt/main_test.go

@@ -0,0 +1,75 @@
+package main_test
+
+import (
+	"io/ioutil"
+	"os"
+	"strings"
+	"testing"
+
+	"github.com/boltdb/bolt"
+	. "github.com/boltdb/bolt/cmd/bolt"
+	"github.com/stretchr/testify/assert"
+)
+
+// Ensure that a value can be retrieved from the CLI.
+func TestGet(t *testing.T) {
+	SetTestMode(true)
+	open(func(db *bolt.DB) {
+		db.Do(func(tx *bolt.Tx) error {
+			tx.CreateBucket("widgets")
+			tx.Bucket("widgets").Put([]byte("foo"), []byte("bar"))
+			return nil
+		})
+		output := run("get", db.Path(), "widgets", "foo")
+		assert.Equal(t, "bar", output)
+	})
+}
+
+// Ensure that an error is reported if the database is not found.
+func TestGetDBNotFound(t *testing.T) {
+	SetTestMode(true)
+	output := run("get", "no/such/db", "widgets", "foo")
+	assert.Equal(t, "stat no/such/db: no such file or directory", output)
+}
+
+// Ensure that an error is reported if the bucket is not found.
+func TestGetBucketNotFound(t *testing.T) {
+	SetTestMode(true)
+	open(func(db *bolt.DB) {
+		output := run("get", db.Path(), "widgets", "foo")
+		assert.Equal(t, "bucket not found: widgets", output)
+	})
+}
+
+// Ensure that an error is reported if the key is not found.
+func TestGetKeyNotFound(t *testing.T) {
+	SetTestMode(true)
+	open(func(db *bolt.DB) {
+		db.Do(func(tx *bolt.Tx) error {
+			return tx.CreateBucket("widgets")
+		})
+		output := run("get", db.Path(), "widgets", "foo")
+		assert.Equal(t, "key not found: foo", output)
+	})
+}
+
+// open creates and opens a Bolt database in the temp directory.
+func open(fn func(*bolt.DB)) {
+	f, _ := ioutil.TempFile("", "bolt-")
+	f.Close()
+	os.Remove(f.Name())
+	defer os.RemoveAll(f.Name())
+
+	db, err := bolt.Open(f.Name(), 0600)
+	if err != nil {
+		panic("db open error: " + err.Error())
+	}
+	fn(db)
+}
+
+// run executes a command against the CLI and returns the output.
+func run(args ...string) string {
+	args = append([]string{"bolt"}, args...)
+	NewApp().Run(args)
+	return strings.TrimSpace(LogBuffer())
+}