/usr/share/gocode/src/github.com/coreos/bbolt/tx_test.go is in golang-github-coreos-bbolt-dev 1.3.1-coreos.5-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
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import (
"bytes"
"errors"
"fmt"
"log"
"os"
"testing"
"github.com/coreos/bbolt"
)
// TestTx_Check_ReadOnly tests consistency checking on a ReadOnly database.
func TestTx_Check_ReadOnly(t *testing.T) {
db := MustOpenDB()
defer db.Close()
if err := db.Update(func(tx *bolt.Tx) error {
b, err := tx.CreateBucket([]byte("widgets"))
if err != nil {
t.Fatal(err)
}
if err := b.Put([]byte("foo"), []byte("bar")); err != nil {
t.Fatal(err)
}
return nil
}); err != nil {
t.Fatal(err)
}
if err := db.DB.Close(); err != nil {
t.Fatal(err)
}
readOnlyDB, err := bolt.Open(db.f, 0666, &bolt.Options{ReadOnly: true})
if err != nil {
t.Fatal(err)
}
defer readOnlyDB.Close()
tx, err := readOnlyDB.Begin(false)
if err != nil {
t.Fatal(err)
}
// ReadOnly DB will load freelist on Check call.
numChecks := 2
errc := make(chan error, numChecks)
check := func() {
err, _ := <-tx.Check()
errc <- err
}
// Ensure the freelist is not reloaded and does not race.
for i := 0; i < numChecks; i++ {
go check()
}
for i := 0; i < numChecks; i++ {
if err := <-errc; err != nil {
t.Fatal(err)
}
}
}
// Ensure that committing a closed transaction returns an error.
func TestTx_Commit_ErrTxClosed(t *testing.T) {
db := MustOpenDB()
defer db.MustClose()
tx, err := db.Begin(true)
if err != nil {
t.Fatal(err)
}
if _, err := tx.CreateBucket([]byte("foo")); err != nil {
t.Fatal(err)
}
if err := tx.Commit(); err != nil {
t.Fatal(err)
}
if err := tx.Commit(); err != bolt.ErrTxClosed {
t.Fatalf("unexpected error: %s", err)
}
}
// Ensure that rolling back a closed transaction returns an error.
func TestTx_Rollback_ErrTxClosed(t *testing.T) {
db := MustOpenDB()
defer db.MustClose()
tx, err := db.Begin(true)
if err != nil {
t.Fatal(err)
}
if err := tx.Rollback(); err != nil {
t.Fatal(err)
}
if err := tx.Rollback(); err != bolt.ErrTxClosed {
t.Fatalf("unexpected error: %s", err)
}
}
// Ensure that committing a read-only transaction returns an error.
func TestTx_Commit_ErrTxNotWritable(t *testing.T) {
db := MustOpenDB()
defer db.MustClose()
tx, err := db.Begin(false)
if err != nil {
t.Fatal(err)
}
if err := tx.Commit(); err != bolt.ErrTxNotWritable {
t.Fatal(err)
}
}
// Ensure that a transaction can retrieve a cursor on the root bucket.
func TestTx_Cursor(t *testing.T) {
db := MustOpenDB()
defer db.MustClose()
if err := db.Update(func(tx *bolt.Tx) error {
if _, err := tx.CreateBucket([]byte("widgets")); err != nil {
t.Fatal(err)
}
if _, err := tx.CreateBucket([]byte("woojits")); err != nil {
t.Fatal(err)
}
c := tx.Cursor()
if k, v := c.First(); !bytes.Equal(k, []byte("widgets")) {
t.Fatalf("unexpected key: %v", k)
} else if v != nil {
t.Fatalf("unexpected value: %v", v)
}
if k, v := c.Next(); !bytes.Equal(k, []byte("woojits")) {
t.Fatalf("unexpected key: %v", k)
} else if v != nil {
t.Fatalf("unexpected value: %v", v)
}
if k, v := c.Next(); k != nil {
t.Fatalf("unexpected key: %v", k)
} else if v != nil {
t.Fatalf("unexpected value: %v", k)
}
return nil
}); err != nil {
t.Fatal(err)
}
}
// Ensure that creating a bucket with a read-only transaction returns an error.
func TestTx_CreateBucket_ErrTxNotWritable(t *testing.T) {
db := MustOpenDB()
defer db.MustClose()
if err := db.View(func(tx *bolt.Tx) error {
_, err := tx.CreateBucket([]byte("foo"))
if err != bolt.ErrTxNotWritable {
t.Fatalf("unexpected error: %s", err)
}
return nil
}); err != nil {
t.Fatal(err)
}
}
// Ensure that creating a bucket on a closed transaction returns an error.
func TestTx_CreateBucket_ErrTxClosed(t *testing.T) {
db := MustOpenDB()
defer db.MustClose()
tx, err := db.Begin(true)
if err != nil {
t.Fatal(err)
}
if err := tx.Commit(); err != nil {
t.Fatal(err)
}
if _, err := tx.CreateBucket([]byte("foo")); err != bolt.ErrTxClosed {
t.Fatalf("unexpected error: %s", err)
}
}
// Ensure that a Tx can retrieve a bucket.
func TestTx_Bucket(t *testing.T) {
db := MustOpenDB()
defer db.MustClose()
if err := db.Update(func(tx *bolt.Tx) error {
if _, err := tx.CreateBucket([]byte("widgets")); err != nil {
t.Fatal(err)
}
if tx.Bucket([]byte("widgets")) == nil {
t.Fatal("expected bucket")
}
return nil
}); err != nil {
t.Fatal(err)
}
}
// Ensure that a Tx retrieving a non-existent key returns nil.
func TestTx_Get_NotFound(t *testing.T) {
db := MustOpenDB()
defer db.MustClose()
if err := db.Update(func(tx *bolt.Tx) error {
b, err := tx.CreateBucket([]byte("widgets"))
if err != nil {
t.Fatal(err)
}
if err := b.Put([]byte("foo"), []byte("bar")); err != nil {
t.Fatal(err)
}
if b.Get([]byte("no_such_key")) != nil {
t.Fatal("expected nil value")
}
return nil
}); err != nil {
t.Fatal(err)
}
}
// Ensure that a bucket can be created and retrieved.
func TestTx_CreateBucket(t *testing.T) {
db := MustOpenDB()
defer db.MustClose()
// Create a bucket.
if err := db.Update(func(tx *bolt.Tx) error {
b, err := tx.CreateBucket([]byte("widgets"))
if err != nil {
t.Fatal(err)
} else if b == nil {
t.Fatal("expected bucket")
}
return nil
}); err != nil {
t.Fatal(err)
}
// Read the bucket through a separate transaction.
if err := db.View(func(tx *bolt.Tx) error {
if tx.Bucket([]byte("widgets")) == nil {
t.Fatal("expected bucket")
}
return nil
}); err != nil {
t.Fatal(err)
}
}
// Ensure that a bucket can be created if it doesn't already exist.
func TestTx_CreateBucketIfNotExists(t *testing.T) {
db := MustOpenDB()
defer db.MustClose()
if err := db.Update(func(tx *bolt.Tx) error {
// Create bucket.
if b, err := tx.CreateBucketIfNotExists([]byte("widgets")); err != nil {
t.Fatal(err)
} else if b == nil {
t.Fatal("expected bucket")
}
// Create bucket again.
if b, err := tx.CreateBucketIfNotExists([]byte("widgets")); err != nil {
t.Fatal(err)
} else if b == nil {
t.Fatal("expected bucket")
}
return nil
}); err != nil {
t.Fatal(err)
}
// Read the bucket through a separate transaction.
if err := db.View(func(tx *bolt.Tx) error {
if tx.Bucket([]byte("widgets")) == nil {
t.Fatal("expected bucket")
}
return nil
}); err != nil {
t.Fatal(err)
}
}
// Ensure transaction returns an error if creating an unnamed bucket.
func TestTx_CreateBucketIfNotExists_ErrBucketNameRequired(t *testing.T) {
db := MustOpenDB()
defer db.MustClose()
if err := db.Update(func(tx *bolt.Tx) error {
if _, err := tx.CreateBucketIfNotExists([]byte{}); err != bolt.ErrBucketNameRequired {
t.Fatalf("unexpected error: %s", err)
}
if _, err := tx.CreateBucketIfNotExists(nil); err != bolt.ErrBucketNameRequired {
t.Fatalf("unexpected error: %s", err)
}
return nil
}); err != nil {
t.Fatal(err)
}
}
// Ensure that a bucket cannot be created twice.
func TestTx_CreateBucket_ErrBucketExists(t *testing.T) {
db := MustOpenDB()
defer db.MustClose()
// Create a bucket.
if err := db.Update(func(tx *bolt.Tx) error {
if _, err := tx.CreateBucket([]byte("widgets")); err != nil {
t.Fatal(err)
}
return nil
}); err != nil {
t.Fatal(err)
}
// Create the same bucket again.
if err := db.Update(func(tx *bolt.Tx) error {
if _, err := tx.CreateBucket([]byte("widgets")); err != bolt.ErrBucketExists {
t.Fatalf("unexpected error: %s", err)
}
return nil
}); err != nil {
t.Fatal(err)
}
}
// Ensure that a bucket is created with a non-blank name.
func TestTx_CreateBucket_ErrBucketNameRequired(t *testing.T) {
db := MustOpenDB()
defer db.MustClose()
if err := db.Update(func(tx *bolt.Tx) error {
if _, err := tx.CreateBucket(nil); err != bolt.ErrBucketNameRequired {
t.Fatalf("unexpected error: %s", err)
}
return nil
}); err != nil {
t.Fatal(err)
}
}
// Ensure that a bucket can be deleted.
func TestTx_DeleteBucket(t *testing.T) {
db := MustOpenDB()
defer db.MustClose()
// Create a bucket and add a value.
if err := db.Update(func(tx *bolt.Tx) error {
b, err := tx.CreateBucket([]byte("widgets"))
if err != nil {
t.Fatal(err)
}
if err := b.Put([]byte("foo"), []byte("bar")); err != nil {
t.Fatal(err)
}
return nil
}); err != nil {
t.Fatal(err)
}
// Delete the bucket and make sure we can't get the value.
if err := db.Update(func(tx *bolt.Tx) error {
if err := tx.DeleteBucket([]byte("widgets")); err != nil {
t.Fatal(err)
}
if tx.Bucket([]byte("widgets")) != nil {
t.Fatal("unexpected bucket")
}
return nil
}); err != nil {
t.Fatal(err)
}
if err := db.Update(func(tx *bolt.Tx) error {
// Create the bucket again and make sure there's not a phantom value.
b, err := tx.CreateBucket([]byte("widgets"))
if err != nil {
t.Fatal(err)
}
if v := b.Get([]byte("foo")); v != nil {
t.Fatalf("unexpected phantom value: %v", v)
}
return nil
}); err != nil {
t.Fatal(err)
}
}
// Ensure that deleting a bucket on a closed transaction returns an error.
func TestTx_DeleteBucket_ErrTxClosed(t *testing.T) {
db := MustOpenDB()
defer db.MustClose()
tx, err := db.Begin(true)
if err != nil {
t.Fatal(err)
}
if err := tx.Commit(); err != nil {
t.Fatal(err)
}
if err := tx.DeleteBucket([]byte("foo")); err != bolt.ErrTxClosed {
t.Fatalf("unexpected error: %s", err)
}
}
// Ensure that deleting a bucket with a read-only transaction returns an error.
func TestTx_DeleteBucket_ReadOnly(t *testing.T) {
db := MustOpenDB()
defer db.MustClose()
if err := db.View(func(tx *bolt.Tx) error {
if err := tx.DeleteBucket([]byte("foo")); err != bolt.ErrTxNotWritable {
t.Fatalf("unexpected error: %s", err)
}
return nil
}); err != nil {
t.Fatal(err)
}
}
// Ensure that nothing happens when deleting a bucket that doesn't exist.
func TestTx_DeleteBucket_NotFound(t *testing.T) {
db := MustOpenDB()
defer db.MustClose()
if err := db.Update(func(tx *bolt.Tx) error {
if err := tx.DeleteBucket([]byte("widgets")); err != bolt.ErrBucketNotFound {
t.Fatalf("unexpected error: %s", err)
}
return nil
}); err != nil {
t.Fatal(err)
}
}
// Ensure that no error is returned when a tx.ForEach function does not return
// an error.
func TestTx_ForEach_NoError(t *testing.T) {
db := MustOpenDB()
defer db.MustClose()
if err := db.Update(func(tx *bolt.Tx) error {
b, err := tx.CreateBucket([]byte("widgets"))
if err != nil {
t.Fatal(err)
}
if err := b.Put([]byte("foo"), []byte("bar")); err != nil {
t.Fatal(err)
}
if err := tx.ForEach(func(name []byte, b *bolt.Bucket) error {
return nil
}); err != nil {
t.Fatal(err)
}
return nil
}); err != nil {
t.Fatal(err)
}
}
// Ensure that an error is returned when a tx.ForEach function returns an error.
func TestTx_ForEach_WithError(t *testing.T) {
db := MustOpenDB()
defer db.MustClose()
if err := db.Update(func(tx *bolt.Tx) error {
b, err := tx.CreateBucket([]byte("widgets"))
if err != nil {
t.Fatal(err)
}
if err := b.Put([]byte("foo"), []byte("bar")); err != nil {
t.Fatal(err)
}
marker := errors.New("marker")
if err := tx.ForEach(func(name []byte, b *bolt.Bucket) error {
return marker
}); err != marker {
t.Fatalf("unexpected error: %s", err)
}
return nil
}); err != nil {
t.Fatal(err)
}
}
// Ensure that Tx commit handlers are called after a transaction successfully commits.
func TestTx_OnCommit(t *testing.T) {
db := MustOpenDB()
defer db.MustClose()
var x int
if err := db.Update(func(tx *bolt.Tx) error {
tx.OnCommit(func() { x += 1 })
tx.OnCommit(func() { x += 2 })
if _, err := tx.CreateBucket([]byte("widgets")); err != nil {
t.Fatal(err)
}
return nil
}); err != nil {
t.Fatal(err)
} else if x != 3 {
t.Fatalf("unexpected x: %d", x)
}
}
// Ensure that Tx commit handlers are NOT called after a transaction rolls back.
func TestTx_OnCommit_Rollback(t *testing.T) {
db := MustOpenDB()
defer db.MustClose()
var x int
if err := db.Update(func(tx *bolt.Tx) error {
tx.OnCommit(func() { x += 1 })
tx.OnCommit(func() { x += 2 })
if _, err := tx.CreateBucket([]byte("widgets")); err != nil {
t.Fatal(err)
}
return errors.New("rollback this commit")
}); err == nil || err.Error() != "rollback this commit" {
t.Fatalf("unexpected error: %s", err)
} else if x != 0 {
t.Fatalf("unexpected x: %d", x)
}
}
// Ensure that the database can be copied to a file path.
func TestTx_CopyFile(t *testing.T) {
db := MustOpenDB()
defer db.MustClose()
path := tempfile()
if err := db.Update(func(tx *bolt.Tx) error {
b, err := tx.CreateBucket([]byte("widgets"))
if err != nil {
t.Fatal(err)
}
if err := b.Put([]byte("foo"), []byte("bar")); err != nil {
t.Fatal(err)
}
if err := b.Put([]byte("baz"), []byte("bat")); err != nil {
t.Fatal(err)
}
return nil
}); err != nil {
t.Fatal(err)
}
if err := db.View(func(tx *bolt.Tx) error {
return tx.CopyFile(path, 0600)
}); err != nil {
t.Fatal(err)
}
db2, err := bolt.Open(path, 0600, nil)
if err != nil {
t.Fatal(err)
}
if err := db2.View(func(tx *bolt.Tx) error {
if v := tx.Bucket([]byte("widgets")).Get([]byte("foo")); !bytes.Equal(v, []byte("bar")) {
t.Fatalf("unexpected value: %v", v)
}
if v := tx.Bucket([]byte("widgets")).Get([]byte("baz")); !bytes.Equal(v, []byte("bat")) {
t.Fatalf("unexpected value: %v", v)
}
return nil
}); err != nil {
t.Fatal(err)
}
if err := db2.Close(); err != nil {
t.Fatal(err)
}
}
type failWriterError struct{}
func (failWriterError) Error() string {
return "error injected for tests"
}
type failWriter struct {
// fail after this many bytes
After int
}
func (f *failWriter) Write(p []byte) (n int, err error) {
n = len(p)
if n > f.After {
n = f.After
err = failWriterError{}
}
f.After -= n
return n, err
}
// Ensure that Copy handles write errors right.
func TestTx_CopyFile_Error_Meta(t *testing.T) {
db := MustOpenDB()
defer db.MustClose()
if err := db.Update(func(tx *bolt.Tx) error {
b, err := tx.CreateBucket([]byte("widgets"))
if err != nil {
t.Fatal(err)
}
if err := b.Put([]byte("foo"), []byte("bar")); err != nil {
t.Fatal(err)
}
if err := b.Put([]byte("baz"), []byte("bat")); err != nil {
t.Fatal(err)
}
return nil
}); err != nil {
t.Fatal(err)
}
if err := db.View(func(tx *bolt.Tx) error {
return tx.Copy(&failWriter{})
}); err == nil || err.Error() != "meta 0 copy: error injected for tests" {
t.Fatalf("unexpected error: %v", err)
}
}
// Ensure that Copy handles write errors right.
func TestTx_CopyFile_Error_Normal(t *testing.T) {
db := MustOpenDB()
defer db.MustClose()
if err := db.Update(func(tx *bolt.Tx) error {
b, err := tx.CreateBucket([]byte("widgets"))
if err != nil {
t.Fatal(err)
}
if err := b.Put([]byte("foo"), []byte("bar")); err != nil {
t.Fatal(err)
}
if err := b.Put([]byte("baz"), []byte("bat")); err != nil {
t.Fatal(err)
}
return nil
}); err != nil {
t.Fatal(err)
}
if err := db.View(func(tx *bolt.Tx) error {
return tx.Copy(&failWriter{3 * db.Info().PageSize})
}); err == nil || err.Error() != "error injected for tests" {
t.Fatalf("unexpected error: %v", err)
}
}
// TestTx_releaseRange ensures db.freePages handles page releases
// correctly when there are transaction that are no longer reachable
// via any read/write transactions and are "between" ongoing read
// transactions, which requires they must be freed by
// freelist.releaseRange.
func TestTx_releaseRange(t *testing.T) {
// Set initial mmap size well beyond the limit we will hit in this
// test, since we are testing with long running read transactions
// and will deadlock if db.grow is triggered.
db := MustOpenWithOption(&bolt.Options{InitialMmapSize: os.Getpagesize() * 100})
defer db.MustClose()
bucket := "bucket"
put := func(key, value string) {
if err := db.Update(func(tx *bolt.Tx) error {
b, err := tx.CreateBucketIfNotExists([]byte(bucket))
if err != nil {
t.Fatal(err)
}
return b.Put([]byte(key), []byte(value))
}); err != nil {
t.Fatal(err)
}
}
del := func(key string) {
if err := db.Update(func(tx *bolt.Tx) error {
b, err := tx.CreateBucketIfNotExists([]byte(bucket))
if err != nil {
t.Fatal(err)
}
return b.Delete([]byte(key))
}); err != nil {
t.Fatal(err)
}
}
getWithTxn := func(txn *bolt.Tx, key string) []byte {
return txn.Bucket([]byte(bucket)).Get([]byte(key))
}
openReadTxn := func() *bolt.Tx {
readTx, err := db.Begin(false)
if err != nil {
t.Fatal(err)
}
return readTx
}
checkWithReadTxn := func(txn *bolt.Tx, key string, wantValue []byte) {
value := getWithTxn(txn, key)
if !bytes.Equal(value, wantValue) {
t.Errorf("Wanted value to be %s for key %s, but got %s", wantValue, key, string(value))
}
}
rollback := func(txn *bolt.Tx) {
if err := txn.Rollback(); err != nil {
t.Fatal(err)
}
}
put("k1", "v1")
rtx1 := openReadTxn()
put("k2", "v2")
hold1 := openReadTxn()
put("k3", "v3")
hold2 := openReadTxn()
del("k3")
rtx2 := openReadTxn()
del("k1")
hold3 := openReadTxn()
del("k2")
hold4 := openReadTxn()
put("k4", "v4")
hold5 := openReadTxn()
// Close the read transactions we established to hold a portion of the pages in pending state.
rollback(hold1)
rollback(hold2)
rollback(hold3)
rollback(hold4)
rollback(hold5)
// Execute a write transaction to trigger a releaseRange operation in the db
// that will free multiple ranges between the remaining open read transactions, now that the
// holds have been rolled back.
put("k4", "v4")
// Check that all long running reads still read correct values.
checkWithReadTxn(rtx1, "k1", []byte("v1"))
checkWithReadTxn(rtx2, "k2", []byte("v2"))
rollback(rtx1)
rollback(rtx2)
// Check that the final state is correct.
rtx7 := openReadTxn()
checkWithReadTxn(rtx7, "k1", nil)
checkWithReadTxn(rtx7, "k2", nil)
checkWithReadTxn(rtx7, "k3", nil)
checkWithReadTxn(rtx7, "k4", []byte("v4"))
rollback(rtx7)
}
func ExampleTx_Rollback() {
// Open the database.
db, err := bolt.Open(tempfile(), 0666, nil)
if err != nil {
log.Fatal(err)
}
defer os.Remove(db.Path())
// Create a bucket.
if err := db.Update(func(tx *bolt.Tx) error {
_, err := tx.CreateBucket([]byte("widgets"))
return err
}); err != nil {
log.Fatal(err)
}
// Set a value for a key.
if err := db.Update(func(tx *bolt.Tx) error {
return tx.Bucket([]byte("widgets")).Put([]byte("foo"), []byte("bar"))
}); err != nil {
log.Fatal(err)
}
// Update the key but rollback the transaction so it never saves.
tx, err := db.Begin(true)
if err != nil {
log.Fatal(err)
}
b := tx.Bucket([]byte("widgets"))
if err := b.Put([]byte("foo"), []byte("baz")); err != nil {
log.Fatal(err)
}
if err := tx.Rollback(); err != nil {
log.Fatal(err)
}
// Ensure that our original value is still set.
if err := db.View(func(tx *bolt.Tx) error {
value := tx.Bucket([]byte("widgets")).Get([]byte("foo"))
fmt.Printf("The value for 'foo' is still: %s\n", value)
return nil
}); err != nil {
log.Fatal(err)
}
// Close database to release file lock.
if err := db.Close(); err != nil {
log.Fatal(err)
}
// Output:
// The value for 'foo' is still: bar
}
func ExampleTx_CopyFile() {
// Open the database.
db, err := bolt.Open(tempfile(), 0666, nil)
if err != nil {
log.Fatal(err)
}
defer os.Remove(db.Path())
// Create a bucket and a key.
if err := db.Update(func(tx *bolt.Tx) error {
b, err := tx.CreateBucket([]byte("widgets"))
if err != nil {
return err
}
if err := b.Put([]byte("foo"), []byte("bar")); err != nil {
return err
}
return nil
}); err != nil {
log.Fatal(err)
}
// Copy the database to another file.
toFile := tempfile()
if err := db.View(func(tx *bolt.Tx) error {
return tx.CopyFile(toFile, 0666)
}); err != nil {
log.Fatal(err)
}
defer os.Remove(toFile)
// Open the cloned database.
db2, err := bolt.Open(toFile, 0666, nil)
if err != nil {
log.Fatal(err)
}
// Ensure that the key exists in the copy.
if err := db2.View(func(tx *bolt.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
}); err != nil {
log.Fatal(err)
}
// Close database to release file lock.
if err := db.Close(); err != nil {
log.Fatal(err)
}
if err := db2.Close(); err != nil {
log.Fatal(err)
}
// Output:
// The value for 'foo' in the clone is: bar
}
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