open-consul/api/lock_test.go
Aestek 24c29e195b kv: do not trigger watches when setting the same value (#5885)
If a KVSet is performed but does not update the entry, do not trigger
watches for this key.
This avoids releasing blocking queries for KV values that did not
actually changed.
2019-06-18 15:06:29 +02:00

585 lines
12 KiB
Go

package api
import (
"log"
"net/http"
"net/http/httptest"
"net/http/httputil"
"strings"
"sync"
"testing"
"time"
"github.com/hashicorp/consul/sdk/testutil/retry"
)
func createTestLock(t *testing.T, c *Client, key string) (*Lock, *Session) {
t.Helper()
session := c.Session()
se := &SessionEntry{
Name: DefaultLockSessionName,
TTL: DefaultLockSessionTTL,
Behavior: SessionBehaviorDelete,
}
id, _, err := session.CreateNoChecks(se, nil)
if err != nil {
t.Fatalf("err: %v", err)
}
opts := &LockOptions{
Key: key,
Session: id,
SessionName: se.Name,
SessionTTL: se.TTL,
}
lock, err := c.LockOpts(opts)
if err != nil {
t.Fatalf("err: %v", err)
}
return lock, session
}
func TestAPI_LockLockUnlock(t *testing.T) {
t.Parallel()
c, s := makeClientWithoutConnect(t)
defer s.Stop()
lock, session := createTestLock(t, c, "test/lock")
defer session.Destroy(lock.opts.Session, nil)
// Initial unlock should fail
err := lock.Unlock()
if err != ErrLockNotHeld {
t.Fatalf("err: %v", err)
}
// Should work
leaderCh, err := lock.Lock(nil)
if err != nil {
t.Fatalf("err: %v", err)
}
if leaderCh == nil {
t.Fatalf("not leader")
}
// Double lock should fail
_, err = lock.Lock(nil)
if err != ErrLockHeld {
t.Fatalf("err: %v", err)
}
// Should be leader
select {
case <-leaderCh:
t.Fatalf("should be leader")
default:
}
// Initial unlock should work
err = lock.Unlock()
if err != nil {
t.Fatalf("err: %v", err)
}
// Double unlock should fail
err = lock.Unlock()
if err != ErrLockNotHeld {
t.Fatalf("err: %v", err)
}
// Should lose leadership
select {
case <-leaderCh:
case <-time.After(time.Second):
t.Fatalf("should not be leader")
}
}
func TestAPI_LockForceInvalidate(t *testing.T) {
t.Parallel()
c, s := makeClientWithoutConnect(t)
defer s.Stop()
retry.Run(t, func(r *retry.R) {
lock, session := createTestLock(t, c, "test/lock")
defer session.Destroy(lock.opts.Session, nil)
// Should work
leaderCh, err := lock.Lock(nil)
if err != nil {
t.Fatalf("err: %v", err)
}
if leaderCh == nil {
t.Fatalf("not leader")
}
defer lock.Unlock()
go func() {
// Nuke the session, simulator an operator invalidation
// or a health check failure
session := c.Session()
session.Destroy(lock.lockSession, nil)
}()
// Should loose leadership
select {
case <-leaderCh:
case <-time.After(time.Second):
t.Fatalf("should not be leader")
}
})
}
func TestAPI_LockDeleteKey(t *testing.T) {
t.Parallel()
c, s := makeClientWithoutConnect(t)
defer s.Stop()
// This uncovered some issues around special-case handling of low index
// numbers where it would work with a low number but fail for higher
// ones, so we loop this a bit to sweep the index up out of that
// territory.
for i := 0; i < 10; i++ {
func() {
lock, session := createTestLock(t, c, "test/lock")
defer session.Destroy(lock.opts.Session, nil)
// Should work
leaderCh, err := lock.Lock(nil)
if err != nil {
t.Fatalf("err: %v", err)
}
if leaderCh == nil {
t.Fatalf("not leader")
}
defer lock.Unlock()
go func() {
// Nuke the key, simulate an operator intervention
kv := c.KV()
kv.Delete("test/lock", nil)
}()
// Should loose leadership
select {
case <-leaderCh:
case <-time.After(10 * time.Second):
t.Fatalf("should not be leader")
}
}()
}
}
func TestAPI_LockContend(t *testing.T) {
t.Parallel()
c, s := makeClientWithoutConnect(t)
defer s.Stop()
wg := &sync.WaitGroup{}
acquired := make([]bool, 3)
for idx := range acquired {
wg.Add(1)
go func(idx int) {
defer wg.Done()
lock, session := createTestLock(t, c, "test/lock")
defer session.Destroy(lock.opts.Session, nil)
// Should work eventually, will contend
leaderCh, err := lock.Lock(nil)
if err != nil {
t.Fatalf("err: %v", err)
}
if leaderCh == nil {
t.Fatalf("not leader")
}
defer lock.Unlock()
log.Printf("Contender %d acquired", idx)
// Set acquired and then leave
acquired[idx] = true
}(idx)
}
// Wait for termination
doneCh := make(chan struct{})
go func() {
wg.Wait()
close(doneCh)
}()
// Wait for everybody to get a turn
select {
case <-doneCh:
case <-time.After(3 * DefaultLockRetryTime):
t.Fatalf("timeout")
}
for idx, did := range acquired {
if !did {
t.Fatalf("contender %d never acquired", idx)
}
}
}
func TestAPI_LockDestroy(t *testing.T) {
t.Parallel()
c, s := makeClientWithoutConnect(t)
defer s.Stop()
lock, session := createTestLock(t, c, "test/lock")
defer session.Destroy(lock.opts.Session, nil)
// Should work
leaderCh, err := lock.Lock(nil)
if err != nil {
t.Fatalf("err: %v", err)
}
if leaderCh == nil {
t.Fatalf("not leader")
}
// Destroy should fail
if err := lock.Destroy(); err != ErrLockHeld {
t.Fatalf("err: %v", err)
}
// Should be able to release
err = lock.Unlock()
if err != nil {
t.Fatalf("err: %v", err)
}
// Acquire with a different lock
l2, session := createTestLock(t, c, "test/lock")
defer session.Destroy(lock.opts.Session, nil)
// Should work
leaderCh, err = l2.Lock(nil)
if err != nil {
t.Fatalf("err: %v", err)
}
if leaderCh == nil {
t.Fatalf("not leader")
}
// Destroy should still fail
if err := lock.Destroy(); err != ErrLockInUse {
t.Fatalf("err: %v", err)
}
// Should release
err = l2.Unlock()
if err != nil {
t.Fatalf("err: %v", err)
}
// Destroy should work
err = lock.Destroy()
if err != nil {
t.Fatalf("err: %v", err)
}
// Double destroy should work
err = l2.Destroy()
if err != nil {
t.Fatalf("err: %v", err)
}
}
func TestAPI_LockConflict(t *testing.T) {
t.Parallel()
c, s := makeClientWithoutConnect(t)
defer s.Stop()
sema, session := createTestSemaphore(t, c, "test/lock/", 2)
defer session.Destroy(sema.opts.Session, nil)
// Should work
lockCh, err := sema.Acquire(nil)
if err != nil {
t.Fatalf("err: %v", err)
}
if lockCh == nil {
t.Fatalf("not hold")
}
defer sema.Release()
lock, session := createTestLock(t, c, "test/lock/.lock")
defer session.Destroy(lock.opts.Session, nil)
// Should conflict with semaphore
_, err = lock.Lock(nil)
if err != ErrLockConflict {
t.Fatalf("err: %v", err)
}
// Should conflict with semaphore
err = lock.Destroy()
if err != ErrLockConflict {
t.Fatalf("err: %v", err)
}
}
func TestAPI_LockReclaimLock(t *testing.T) {
t.Parallel()
c, s := makeClientWithoutConnect(t)
defer s.Stop()
s.WaitForSerfCheck(t)
session, _, err := c.Session().Create(&SessionEntry{}, nil)
if err != nil {
t.Fatalf("err: %v", err)
}
lock, err := c.LockOpts(&LockOptions{Key: "test/lock", Session: session})
if err != nil {
t.Fatalf("err: %v", err)
}
// Should work
leaderCh, err := lock.Lock(nil)
if err != nil {
t.Fatalf("err: %v", err)
}
if leaderCh == nil {
t.Fatalf("not leader")
}
defer lock.Unlock()
l2, err := c.LockOpts(&LockOptions{Key: "test/lock", Session: session})
if err != nil {
t.Fatalf("err: %v", err)
}
reclaimed := make(chan (<-chan struct{}), 1)
go func() {
l2Ch, err := l2.Lock(nil)
if err != nil {
t.Fatalf("not locked: %v", err)
}
reclaimed <- l2Ch
}()
// Should reclaim the lock
var leader2Ch <-chan struct{}
select {
case leader2Ch = <-reclaimed:
case <-time.After(time.Second):
t.Fatalf("should have locked")
}
// unlock should work
err = l2.Unlock()
if err != nil {
t.Fatalf("err: %v", err)
}
//Both locks should see the unlock
select {
case <-leader2Ch:
case <-time.After(time.Second):
t.Fatalf("should not be leader")
}
select {
case <-leaderCh:
case <-time.After(time.Second):
t.Fatalf("should not be leader")
}
}
func TestAPI_LockMonitorRetry(t *testing.T) {
t.Parallel()
raw, s := makeClientWithoutConnect(t)
defer s.Stop()
s.WaitForSerfCheck(t)
// Set up a server that always responds with 500 errors.
failer := func(w http.ResponseWriter, req *http.Request) {
w.WriteHeader(500)
}
outage := httptest.NewServer(http.HandlerFunc(failer))
defer outage.Close()
// Set up a reverse proxy that will send some requests to the
// 500 server and pass everything else through to the real Consul
// server.
var mutex sync.Mutex
errors := 0
director := func(req *http.Request) {
mutex.Lock()
defer mutex.Unlock()
req.URL.Scheme = "http"
if errors > 0 && req.Method == "GET" && strings.Contains(req.URL.Path, "/v1/kv/test/lock") {
req.URL.Host = outage.URL[7:] // Strip off "http://".
errors--
} else {
req.URL.Host = raw.config.Address
}
}
proxy := httptest.NewServer(&httputil.ReverseProxy{Director: director})
defer proxy.Close()
// Make another client that points at the proxy instead of the real
// Consul server.
config := raw.config
config.Address = proxy.URL[7:] // Strip off "http://".
c, err := NewClient(&config)
if err != nil {
t.Fatalf("err: %v", err)
}
// Set up a lock with retries enabled.
opts := &LockOptions{
Key: "test/lock",
SessionTTL: "60s",
MonitorRetries: 3,
}
lock, err := c.LockOpts(opts)
if err != nil {
t.Fatalf("err: %v", err)
}
// Make sure the default got set.
if lock.opts.MonitorRetryTime != DefaultMonitorRetryTime {
t.Fatalf("bad: %d", lock.opts.MonitorRetryTime)
}
// Now set a custom time for the test.
opts.MonitorRetryTime = 250 * time.Millisecond
lock, err = c.LockOpts(opts)
if err != nil {
t.Fatalf("err: %v", err)
}
if lock.opts.MonitorRetryTime != 250*time.Millisecond {
t.Fatalf("bad: %d", lock.opts.MonitorRetryTime)
}
// Should get the lock.
leaderCh, err := lock.Lock(nil)
if err != nil {
t.Fatalf("err: %v", err)
}
if leaderCh == nil {
t.Fatalf("not leader")
}
// Poke the key using the raw client to force the monitor to wake up
// and check the lock again. This time we will return errors for some
// of the responses.
mutex.Lock()
errors = 2
mutex.Unlock()
pair, _, err := raw.KV().Get("test/lock", &QueryOptions{})
if err != nil {
t.Fatalf("err: %v", err)
}
pair.Value = []byte{1}
if _, err := raw.KV().Put(pair, &WriteOptions{}); err != nil {
t.Fatalf("err: %v", err)
}
time.Sleep(5 * opts.MonitorRetryTime)
// Should still be the leader.
select {
case <-leaderCh:
t.Fatalf("should be leader")
default:
}
// Now return an overwhelming number of errors.
mutex.Lock()
errors = 10
mutex.Unlock()
pair.Value = []byte{2}
if _, err := raw.KV().Put(pair, &WriteOptions{}); err != nil {
t.Fatalf("err: %v", err)
}
time.Sleep(5 * opts.MonitorRetryTime)
// Should lose leadership.
select {
case <-leaderCh:
case <-time.After(time.Second):
t.Fatalf("should not be leader")
}
}
func TestAPI_LockOneShot(t *testing.T) {
t.Parallel()
c, s := makeClientWithoutConnect(t)
defer s.Stop()
s.WaitForSerfCheck(t)
// Set up a lock as a one-shot.
opts := &LockOptions{
Key: "test/lock",
LockTryOnce: true,
}
lock, err := c.LockOpts(opts)
if err != nil {
t.Fatalf("err: %v", err)
}
// Make sure the default got set.
if lock.opts.LockWaitTime != DefaultLockWaitTime {
t.Fatalf("bad: %d", lock.opts.LockWaitTime)
}
// Now set a custom time for the test.
opts.LockWaitTime = 250 * time.Millisecond
lock, err = c.LockOpts(opts)
if err != nil {
t.Fatalf("err: %v", err)
}
if lock.opts.LockWaitTime != 250*time.Millisecond {
t.Fatalf("bad: %d", lock.opts.LockWaitTime)
}
// Should get the lock.
ch, err := lock.Lock(nil)
if err != nil {
t.Fatalf("err: %v", err)
}
if ch == nil {
t.Fatalf("not leader")
}
// Now try with another session.
contender, err := c.LockOpts(opts)
if err != nil {
t.Fatalf("err: %v", err)
}
start := time.Now()
ch, err = contender.Lock(nil)
if err != nil {
t.Fatalf("err: %v", err)
}
if ch != nil {
t.Fatalf("should not be leader")
}
diff := time.Since(start)
if diff < contender.opts.LockWaitTime || diff > 2*contender.opts.LockWaitTime {
t.Fatalf("time out of bounds: %9.6f", diff.Seconds())
}
// Unlock and then make sure the contender can get it.
if err := lock.Unlock(); err != nil {
t.Fatalf("err: %v", err)
}
ch, err = contender.Lock(nil)
if err != nil {
t.Fatalf("err: %v", err)
}
if ch == nil {
t.Fatalf("should be leader")
}
}