diff --git a/db.go b/db.go index c768ce3..1a1f997 100644 --- a/db.go +++ b/db.go @@ -4,7 +4,6 @@ import ( "errors" "fmt" "hash/fnv" - "io" "os" "strings" "sync" @@ -483,65 +482,6 @@ func (db *DB) View(fn func(*Tx) error) error { return nil } -// Copy writes the entire database to a writer. -// A reader transaction is maintained during the copy so it is safe to continue -// using the database while a copy is in progress. -func (db *DB) Copy(w io.Writer) error { - // Maintain a reader transaction so pages don't get reclaimed. - t, err := db.Begin(false) - if err != nil { - return err - } - - // Open reader on the database. - f, err := os.Open(db.path) - if err != nil { - _ = t.Rollback() - return err - } - - // Copy the meta pages. - db.metalock.Lock() - _, err = io.CopyN(w, f, int64(db.pageSize*2)) - db.metalock.Unlock() - if err != nil { - _ = t.Rollback() - _ = f.Close() - return fmt.Errorf("meta copy: %s", err) - } - - // Copy data pages. - if _, err := io.Copy(w, f); err != nil { - _ = t.Rollback() - _ = f.Close() - return err - } - - // Close read transaction and exit. - if err := t.Rollback(); err != nil { - _ = f.Close() - return err - } - return f.Close() -} - -// CopyFile copies the entire database to file at the given path. -// A reader transaction is maintained during the copy so it is safe to continue -// using the database while a copy is in progress. -func (db *DB) CopyFile(path string, mode os.FileMode) error { - f, err := os.OpenFile(path, os.O_RDWR|os.O_CREATE|os.O_TRUNC, mode) - if err != nil { - return err - } - - err = db.Copy(f) - if err != nil { - _ = f.Close() - return err - } - return f.Close() -} - // Stats retrieves ongoing performance stats for the database. // This is only updated when a transaction closes. func (db *DB) Stats() Stats { diff --git a/db_test.go b/db_test.go index 903f65e..7b1f554 100644 --- a/db_test.go +++ b/db_test.go @@ -238,30 +238,6 @@ func TestDB_View_Error(t *testing.T) { }) } -// Ensure that the database can be copied to a file path. -func TestDB_CopyFile(t *testing.T) { - withOpenDB(func(db *DB, path string) { - var dest = tempfile() - db.Update(func(tx *Tx) error { - tx.CreateBucket([]byte("widgets")) - tx.Bucket([]byte("widgets")).Put([]byte("foo"), []byte("bar")) - tx.Bucket([]byte("widgets")).Put([]byte("baz"), []byte("bat")) - return nil - }) - assert.NoError(t, db.CopyFile(dest, 0600)) - - db2, err := Open(dest, 0600) - assert.NoError(t, err) - defer db2.Close() - - db2.View(func(tx *Tx) error { - assert.Equal(t, []byte("bar"), tx.Bucket([]byte("widgets")).Get([]byte("foo"))) - assert.Equal(t, []byte("bat"), tx.Bucket([]byte("widgets")).Get([]byte("baz"))) - return nil - }) - }) -} - // Ensure that an error is returned when a database write fails. func TestDB_Commit_WriteFail(t *testing.T) { t.Skip("pending") // TODO(benbjohnson) @@ -450,39 +426,6 @@ func ExampleDB_Begin_ReadOnly() { // zephyr likes purple } -func ExampleDB_CopyFile() { - // Open the database. - db, _ := Open(tempfile(), 0666) - defer os.Remove(db.Path()) - defer db.Close() - - // Create a bucket and a key. - db.Update(func(tx *Tx) error { - tx.CreateBucket([]byte("widgets")) - tx.Bucket([]byte("widgets")).Put([]byte("foo"), []byte("bar")) - return nil - }) - - // Copy the database to another file. - toFile := tempfile() - db.CopyFile(toFile, 0666) - defer os.Remove(toFile) - - // Open the cloned database. - db2, _ := Open(toFile, 0666) - defer db2.Close() - - // Ensure that the key exists in the copy. - db2.View(func(tx *Tx) error { - value := tx.Bucket([]byte("widgets")).Get([]byte("foo")) - fmt.Printf("The value for 'foo' in the clone is: %s\n", value) - return nil - }) - - // Output: - // The value for 'foo' in the clone is: bar -} - // tempfile returns a temporary file path. func tempfile() string { f, _ := ioutil.TempFile("", "bolt-") @@ -523,7 +466,7 @@ func mustCheck(db *DB) { if err := db.Check(); err != nil { // Copy db off first. var path = tempfile() - db.CopyFile(path, 0600) + db.View(func(tx *Tx) error { return tx.CopyFile(path, 0600) }) if errors, ok := err.(ErrorList); ok { for _, err := range errors { @@ -564,7 +507,7 @@ func truncDuration(d time.Duration) string { // copyAndFailNow copies a database to a new location and then fails then test. func copyAndFailNow(t *testing.T, db *DB) { path := tempfile() - db.CopyFile(path, 0600) + db.View(func(tx *Tx) error { return tx.CopyFile(path, 0600) }) fmt.Println("db copied to: ", path) t.FailNow() } diff --git a/tx.go b/tx.go index fd456eb..35d47f8 100644 --- a/tx.go +++ b/tx.go @@ -3,6 +3,8 @@ package bolt import ( "errors" "fmt" + "io" + "os" "sort" "time" "unsafe" @@ -227,6 +229,55 @@ func (tx *Tx) close() { tx.db = nil } +// Copy writes the entire database to a writer. +// A reader transaction is maintained during the copy so it is safe to continue +// using the database while a copy is in progress. +func (tx *Tx) Copy(w io.Writer) error { + + // Open reader on the database. + f, err := os.Open(tx.db.path) + if err != nil { + _ = tx.Rollback() + return err + } + + // Copy the meta pages. + tx.db.metalock.Lock() + _, err = io.CopyN(w, f, int64(tx.db.pageSize*2)) + tx.db.metalock.Unlock() + if err != nil { + _ = tx.Rollback() + _ = f.Close() + return fmt.Errorf("meta copy: %s", err) + } + + // Copy data pages. + if _, err := io.Copy(w, f); err != nil { + _ = tx.Rollback() + _ = f.Close() + return err + } + + return f.Close() +} + +// CopyFile copies the entire database to file at the given path. +// A reader transaction is maintained during the copy so it is safe to continue +// using the database while a copy is in progress. +func (tx *Tx) CopyFile(path string, mode os.FileMode) error { + f, err := os.OpenFile(path, os.O_RDWR|os.O_CREATE|os.O_TRUNC, mode) + if err != nil { + return err + } + + err = tx.Copy(f) + if err != nil { + _ = f.Close() + return err + } + return f.Close() +} + // Check performs several consistency checks on the database for this transaction. // An error is returned if any inconsistency is found or if executed on a read-only transaction. func (tx *Tx) Check() error { diff --git a/tx_test.go b/tx_test.go index 7bf369b..05e7466 100644 --- a/tx_test.go +++ b/tx_test.go @@ -313,6 +313,31 @@ func TestTx_Check_Corrupt(t *testing.T) { assert.Equal(t, "check fail: 1 errors occurred: page 3: already freed", msg) } +// Ensure that the database can be copied to a file path. +func TestTx_CopyFile(t *testing.T) { + withOpenDB(func(db *DB, path string) { + var dest = tempfile() + db.Update(func(tx *Tx) error { + tx.CreateBucket([]byte("widgets")) + tx.Bucket([]byte("widgets")).Put([]byte("foo"), []byte("bar")) + tx.Bucket([]byte("widgets")).Put([]byte("baz"), []byte("bat")) + return nil + }) + + assert.NoError(t, db.View(func(tx *Tx) error { return tx.CopyFile(dest, 0600) })) + + db2, err := Open(dest, 0600) + assert.NoError(t, err) + defer db2.Close() + + db2.View(func(tx *Tx) error { + assert.Equal(t, []byte("bar"), tx.Bucket([]byte("widgets")).Get([]byte("foo"))) + assert.Equal(t, []byte("bat"), tx.Bucket([]byte("widgets")).Get([]byte("baz"))) + return nil + }) + }) +} + func ExampleTx_Rollback() { // Open the database. db, _ := Open(tempfile(), 0666) @@ -346,3 +371,36 @@ func ExampleTx_Rollback() { // Output: // The value for 'foo' is still: bar } + +func ExampleTx_CopyFile() { + // Open the database. + db, _ := Open(tempfile(), 0666) + defer os.Remove(db.Path()) + defer db.Close() + + // Create a bucket and a key. + db.Update(func(tx *Tx) error { + tx.CreateBucket([]byte("widgets")) + tx.Bucket([]byte("widgets")).Put([]byte("foo"), []byte("bar")) + return nil + }) + + // Copy the database to another file. + toFile := tempfile() + db.View(func(tx *Tx) error { return tx.CopyFile(toFile, 0666) }) + defer os.Remove(toFile) + + // Open the cloned database. + db2, _ := Open(toFile, 0666) + defer db2.Close() + + // Ensure that the key exists in the copy. + db2.View(func(tx *Tx) error { + value := tx.Bucket([]byte("widgets")).Get([]byte("foo")) + fmt.Printf("The value for 'foo' in the clone is: %s\n", value) + return nil + }) + + // Output: + // The value for 'foo' in the clone is: bar +}