package cache import ( "context" "errors" "fmt" "sort" "sync" "sync/atomic" "testing" "time" "github.com/hashicorp/consul/sdk/testutil" "github.com/stretchr/testify/assert" "github.com/stretchr/testify/mock" "github.com/stretchr/testify/require" ) // Test a basic Get with no indexes (and therefore no blocking queries). func TestCacheGet_noIndex(t *testing.T) { t.Parallel() require := require.New(t) typ := TestType(t) defer typ.AssertExpectations(t) c := New(Options{}) c.RegisterType("t", typ) // Configure the type typ.Static(FetchResult{Value: 42}, nil).Times(1) // Get, should fetch req := TestRequest(t, RequestInfo{Key: "hello"}) result, meta, err := c.Get(context.Background(), "t", req) require.NoError(err) require.Equal(42, result) require.False(meta.Hit) // Get, should not fetch since we already have a satisfying value result, meta, err = c.Get(context.Background(), "t", req) require.NoError(err) require.Equal(42, result) require.True(meta.Hit) // Sleep a tiny bit just to let maybe some background calls happen // then verify that we still only got the one call time.Sleep(20 * time.Millisecond) typ.AssertExpectations(t) } // Test a basic Get with no index and a failed fetch. func TestCacheGet_initError(t *testing.T) { t.Parallel() require := require.New(t) typ := TestType(t) defer typ.AssertExpectations(t) c := New(Options{}) c.RegisterType("t", typ) // Configure the type fetcherr := fmt.Errorf("error") typ.Static(FetchResult{}, fetcherr).Times(2) // Get, should fetch req := TestRequest(t, RequestInfo{Key: "hello"}) result, meta, err := c.Get(context.Background(), "t", req) require.Error(err) require.Nil(result) require.False(meta.Hit) // Get, should fetch again since our last fetch was an error result, meta, err = c.Get(context.Background(), "t", req) require.Error(err) require.Nil(result) require.False(meta.Hit) // Sleep a tiny bit just to let maybe some background calls happen // then verify that we still only got the one call time.Sleep(20 * time.Millisecond) typ.AssertExpectations(t) } // Test a cached error is replaced by a successful result. See // https://github.com/hashicorp/consul/issues/4480 func TestCacheGet_cachedErrorsDontStick(t *testing.T) { t.Parallel() require := require.New(t) typ := TestType(t) defer typ.AssertExpectations(t) c := New(Options{}) c.RegisterType("t", typ) // Configure the type fetcherr := fmt.Errorf("initial error") // First fetch errors, subsequent fetches are successful and then block typ.Static(FetchResult{}, fetcherr).Times(1) typ.Static(FetchResult{Value: 42, Index: 123}, nil).Times(1) // We trigger this to return same value to simulate a timeout. triggerCh := make(chan time.Time) typ.Static(FetchResult{Value: 42, Index: 123}, nil).WaitUntil(triggerCh) // Get, should fetch and get error req := TestRequest(t, RequestInfo{Key: "hello"}) result, meta, err := c.Get(context.Background(), "t", req) require.Error(err) require.Nil(result) require.False(meta.Hit) // Get, should fetch again since our last fetch was an error, but get success result, meta, err = c.Get(context.Background(), "t", req) require.NoError(err) require.Equal(42, result) require.False(meta.Hit) // Now get should block until timeout and then get the same response NOT the // cached error. getCh1 := TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{ Key: "hello", MinIndex: 123, // We _don't_ set a timeout here since that doesn't trigger the bug - the // bug occurs when the Fetch call times out and returns the same value when // an error is set. If it returns a new value the blocking loop works too. })) time.AfterFunc(50*time.Millisecond, func() { // "Timeout" the Fetch after a short time. close(triggerCh) }) select { case result := <-getCh1: t.Fatalf("result or error returned before an update happened. "+ "If this is nil look above for the error log: %v", result) case <-time.After(100 * time.Millisecond): // It _should_ keep blocking for a new value here } // Sleep a tiny bit just to let maybe some background calls happen // then verify the calls. time.Sleep(20 * time.Millisecond) typ.AssertExpectations(t) } // Test a Get with a request that returns a blank cache key. This should // force a backend request and skip the cache entirely. func TestCacheGet_blankCacheKey(t *testing.T) { t.Parallel() require := require.New(t) typ := TestType(t) defer typ.AssertExpectations(t) c := New(Options{}) c.RegisterType("t", typ) // Configure the type typ.Static(FetchResult{Value: 42}, nil).Times(2) // Get, should fetch req := TestRequest(t, RequestInfo{Key: ""}) result, meta, err := c.Get(context.Background(), "t", req) require.NoError(err) require.Equal(42, result) require.False(meta.Hit) // Get, should not fetch since we already have a satisfying value result, meta, err = c.Get(context.Background(), "t", req) require.NoError(err) require.Equal(42, result) require.False(meta.Hit) // Sleep a tiny bit just to let maybe some background calls happen // then verify that we still only got the one call time.Sleep(20 * time.Millisecond) typ.AssertExpectations(t) } // Test that Get blocks on the initial value func TestCacheGet_blockingInitSameKey(t *testing.T) { t.Parallel() typ := TestType(t) defer typ.AssertExpectations(t) c := New(Options{}) c.RegisterType("t", typ) // Configure the type triggerCh := make(chan time.Time) typ.Static(FetchResult{Value: 42}, nil).WaitUntil(triggerCh).Times(1) // Perform multiple gets getCh1 := TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{Key: "hello"})) getCh2 := TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{Key: "hello"})) // They should block select { case <-getCh1: t.Fatal("should block (ch1)") case <-getCh2: t.Fatal("should block (ch2)") case <-time.After(50 * time.Millisecond): } // Trigger it close(triggerCh) // Should return TestCacheGetChResult(t, getCh1, 42) TestCacheGetChResult(t, getCh2, 42) } // Test that Get with different cache keys both block on initial value // but that the fetches were both properly called. func TestCacheGet_blockingInitDiffKeys(t *testing.T) { t.Parallel() require := require.New(t) typ := TestType(t) defer typ.AssertExpectations(t) c := New(Options{}) c.RegisterType("t", typ) // Keep track of the keys var keysLock sync.Mutex var keys []string // Configure the type triggerCh := make(chan time.Time) typ.Static(FetchResult{Value: 42}, nil). WaitUntil(triggerCh). Times(2). Run(func(args mock.Arguments) { keysLock.Lock() defer keysLock.Unlock() keys = append(keys, args.Get(1).(Request).CacheInfo().Key) }) // Perform multiple gets getCh1 := TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{Key: "hello"})) getCh2 := TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{Key: "goodbye"})) // They should block select { case <-getCh1: t.Fatal("should block (ch1)") case <-getCh2: t.Fatal("should block (ch2)") case <-time.After(50 * time.Millisecond): } // Trigger it close(triggerCh) // Should return both! TestCacheGetChResult(t, getCh1, 42) TestCacheGetChResult(t, getCh2, 42) // Verify proper keys sort.Strings(keys) require.Equal([]string{"goodbye", "hello"}, keys) } // Test a get with an index set will wait until an index that is higher // is set in the cache. func TestCacheGet_blockingIndex(t *testing.T) { t.Parallel() typ := TestType(t) defer typ.AssertExpectations(t) c := New(Options{}) c.RegisterType("t", typ) // Configure the type triggerCh := make(chan time.Time) typ.Static(FetchResult{Value: 1, Index: 4}, nil).Once() typ.Static(FetchResult{Value: 12, Index: 5}, nil).Once() typ.Static(FetchResult{Value: 42, Index: 6}, nil).WaitUntil(triggerCh) // Fetch should block resultCh := TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{ Key: "hello", MinIndex: 5})) // Should block select { case <-resultCh: t.Fatal("should block") case <-time.After(50 * time.Millisecond): } // Wait a bit close(triggerCh) // Should return TestCacheGetChResult(t, resultCh, 42) } func TestCacheGet_cancellation(t *testing.T) { typ := TestType(t) defer typ.AssertExpectations(t) c := New(Options{}) c.RegisterType("t", typ) typ.Static(FetchResult{Value: 1, Index: 4}, nil).Times(0).WaitUntil(time.After(1 * time.Millisecond)) ctx, cancel := context.WithDeadline(context.Background(), time.Now().Add(50*time.Millisecond)) // this is just to keep the linter happy defer cancel() result, _, err := c.Get(ctx, "t", TestRequest(t, RequestInfo{ Key: "hello", MinIndex: 5})) require.Nil(t, result) require.Error(t, err) testutil.RequireErrorContains(t, err, context.DeadlineExceeded.Error()) } // Test a get with an index set will timeout if the fetch doesn't return // anything. func TestCacheGet_blockingIndexTimeout(t *testing.T) { t.Parallel() typ := TestType(t) defer typ.AssertExpectations(t) c := New(Options{}) c.RegisterType("t", typ) // Configure the type triggerCh := make(chan time.Time) typ.Static(FetchResult{Value: 1, Index: 4}, nil).Once() typ.Static(FetchResult{Value: 12, Index: 5}, nil).Once() typ.Static(FetchResult{Value: 42, Index: 6}, nil).WaitUntil(triggerCh) // Fetch should block resultCh := TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{ Key: "hello", MinIndex: 5, Timeout: 200 * time.Millisecond})) // Should block select { case <-resultCh: t.Fatal("should block") case <-time.After(50 * time.Millisecond): } // Should return after more of the timeout select { case result := <-resultCh: require.Equal(t, 12, result) case <-time.After(300 * time.Millisecond): t.Fatal("should've returned") } } // Test a get with an index set with requests returning an error // will return that error. func TestCacheGet_blockingIndexError(t *testing.T) { t.Parallel() typ := TestType(t) defer typ.AssertExpectations(t) c := New(Options{}) c.RegisterType("t", typ) // Configure the type var retries uint32 fetchErr := fmt.Errorf("test fetch error") typ.Static(FetchResult{Value: 1, Index: 4}, nil).Once() typ.Static(FetchResult{Value: nil, Index: 5}, fetchErr).Run(func(args mock.Arguments) { atomic.AddUint32(&retries, 1) }) // First good fetch to populate catch resultCh := TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{Key: "hello"})) TestCacheGetChResult(t, resultCh, 1) // Fetch should not block and should return error resultCh = TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{ Key: "hello", MinIndex: 7, Timeout: 1 * time.Minute})) TestCacheGetChResult(t, resultCh, nil) // Wait a bit time.Sleep(100 * time.Millisecond) // Check the number actual := atomic.LoadUint32(&retries) require.True(t, actual < 10, fmt.Sprintf("actual: %d", actual)) } // Test that if a Type returns an empty value on Fetch that the previous // value is preserved. func TestCacheGet_emptyFetchResult(t *testing.T) { t.Parallel() require := require.New(t) typ := TestType(t) defer typ.AssertExpectations(t) c := New(Options{}) c.RegisterType("t", typ) stateCh := make(chan int, 1) // Configure the type typ.Static(FetchResult{Value: 42, State: 31, Index: 1}, nil).Times(1) // Return different State, it should NOT be ignored typ.Static(FetchResult{Value: nil, State: 32}, nil).Run(func(args mock.Arguments) { // We should get back the original state opts := args.Get(0).(FetchOptions) require.NotNil(opts.LastResult) stateCh <- opts.LastResult.State.(int) }) // Get, should fetch req := TestRequest(t, RequestInfo{Key: "hello"}) result, meta, err := c.Get(context.Background(), "t", req) require.NoError(err) require.Equal(42, result) require.False(meta.Hit) // Get, should not fetch since we already have a satisfying value req = TestRequest(t, RequestInfo{ Key: "hello", MinIndex: 1, Timeout: 100 * time.Millisecond}) result, meta, err = c.Get(context.Background(), "t", req) require.NoError(err) require.Equal(42, result) require.False(meta.Hit) // State delivered to second call should be the result from first call. select { case state := <-stateCh: require.Equal(31, state) case <-time.After(20 * time.Millisecond): t.Fatal("timed out") } // Next request should get the SECOND returned state even though the fetch // returns nil and so the previous result is used. req = TestRequest(t, RequestInfo{ Key: "hello", MinIndex: 1, Timeout: 100 * time.Millisecond}) result, meta, err = c.Get(context.Background(), "t", req) require.NoError(err) require.Equal(42, result) require.False(meta.Hit) select { case state := <-stateCh: require.Equal(32, state) case <-time.After(20 * time.Millisecond): t.Fatal("timed out") } // Sleep a tiny bit just to let maybe some background calls happen // then verify that we still only got the one call time.Sleep(20 * time.Millisecond) typ.AssertExpectations(t) } // Test that a type registered with a periodic refresh will perform // that refresh after the timer is up. func TestCacheGet_periodicRefresh(t *testing.T) { t.Parallel() typ := &MockType{} typ.On("RegisterOptions").Return(RegisterOptions{ Refresh: true, RefreshTimer: 100 * time.Millisecond, QueryTimeout: 5 * time.Minute, }) defer typ.AssertExpectations(t) c := New(Options{}) c.RegisterType("t", typ) // This is a bit weird, but we do this to ensure that the final // call to the Fetch (if it happens, depends on timing) just blocks. triggerCh := make(chan time.Time) defer close(triggerCh) // Configure the type typ.Static(FetchResult{Value: 1, Index: 4}, nil).Once() typ.Static(FetchResult{Value: 12, Index: 5}, nil).Once() typ.Static(FetchResult{Value: 12, Index: 5}, nil).WaitUntil(triggerCh) // Fetch should block resultCh := TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{Key: "hello"})) TestCacheGetChResult(t, resultCh, 1) // Fetch again almost immediately should return old result time.Sleep(5 * time.Millisecond) resultCh = TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{Key: "hello"})) TestCacheGetChResult(t, resultCh, 1) // Wait for the timer time.Sleep(200 * time.Millisecond) resultCh = TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{Key: "hello"})) TestCacheGetChResult(t, resultCh, 12) } // Test that a type registered with a periodic refresh will perform // that refresh after the timer is up. func TestCacheGet_periodicRefreshMultiple(t *testing.T) { t.Parallel() typ := &MockType{} typ.On("RegisterOptions").Return(RegisterOptions{ Refresh: true, RefreshTimer: 0 * time.Millisecond, QueryTimeout: 5 * time.Minute, }) defer typ.AssertExpectations(t) c := New(Options{}) c.RegisterType("t", typ) // This is a bit weird, but we do this to ensure that the final // call to the Fetch (if it happens, depends on timing) just blocks. trigger := make([]chan time.Time, 3) for i := range trigger { trigger[i] = make(chan time.Time) } // Configure the type typ.Static(FetchResult{Value: 1, Index: 4}, nil).Once() typ.Static(FetchResult{Value: 12, Index: 5}, nil).Once().WaitUntil(trigger[0]) typ.Static(FetchResult{Value: 24, Index: 6}, nil).Once().WaitUntil(trigger[1]) typ.Static(FetchResult{Value: 42, Index: 7}, nil).WaitUntil(trigger[2]) // Fetch should block resultCh := TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{Key: "hello"})) TestCacheGetChResult(t, resultCh, 1) // Fetch again almost immediately should return old result time.Sleep(5 * time.Millisecond) resultCh = TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{Key: "hello"})) TestCacheGetChResult(t, resultCh, 1) // Trigger the next, sleep a bit, and verify we get the next result close(trigger[0]) time.Sleep(100 * time.Millisecond) resultCh = TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{Key: "hello"})) TestCacheGetChResult(t, resultCh, 12) // Trigger the next, sleep a bit, and verify we get the next result close(trigger[1]) time.Sleep(100 * time.Millisecond) resultCh = TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{Key: "hello"})) TestCacheGetChResult(t, resultCh, 24) } // Test that a refresh performs a backoff. func TestCacheGet_periodicRefreshErrorBackoff(t *testing.T) { t.Parallel() typ := &MockType{} typ.On("RegisterOptions").Return(RegisterOptions{ Refresh: true, RefreshTimer: 0, QueryTimeout: 5 * time.Minute, }) defer typ.AssertExpectations(t) c := New(Options{}) c.RegisterType("t", typ) // Configure the type var retries uint32 fetchErr := fmt.Errorf("test fetch error") typ.Static(FetchResult{Value: 1, Index: 4}, nil).Once() typ.Static(FetchResult{Value: nil, Index: 5}, fetchErr).Run(func(args mock.Arguments) { atomic.AddUint32(&retries, 1) }) // Fetch resultCh := TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{Key: "hello"})) TestCacheGetChResult(t, resultCh, 1) // Sleep a bit. The refresh will quietly fail in the background. What we // want to verify is that it doesn't retry too much. "Too much" is hard // to measure since its CPU dependent if this test is failing. But due // to the short sleep below, we can calculate about what we'd expect if // backoff IS working. time.Sleep(500 * time.Millisecond) // Fetch should work, we should get a 1 still. Errors are ignored. resultCh = TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{Key: "hello"})) TestCacheGetChResult(t, resultCh, 1) // Check the number actual := atomic.LoadUint32(&retries) require.True(t, actual < 10, fmt.Sprintf("actual: %d", actual)) } // Test that a badly behaved RPC that returns 0 index will perform a backoff. func TestCacheGet_periodicRefreshBadRPCZeroIndexErrorBackoff(t *testing.T) { t.Parallel() typ := &MockType{} typ.On("RegisterOptions").Return(RegisterOptions{ Refresh: true, RefreshTimer: 0, QueryTimeout: 5 * time.Minute, }) defer typ.AssertExpectations(t) c := New(Options{}) c.RegisterType("t", typ) // Configure the type var retries uint32 typ.Static(FetchResult{Value: 0, Index: 0}, nil).Run(func(args mock.Arguments) { atomic.AddUint32(&retries, 1) }) // Fetch resultCh := TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{Key: "hello"})) TestCacheGetChResult(t, resultCh, 0) // Sleep a bit. The refresh will quietly fail in the background. What we // want to verify is that it doesn't retry too much. "Too much" is hard // to measure since its CPU dependent if this test is failing. But due // to the short sleep below, we can calculate about what we'd expect if // backoff IS working. time.Sleep(500 * time.Millisecond) // Fetch should work, we should get a 0 still. Errors are ignored. resultCh = TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{Key: "hello"})) TestCacheGetChResult(t, resultCh, 0) // Check the number actual := atomic.LoadUint32(&retries) require.True(t, actual < 10, fmt.Sprintf("%d retries, should be < 10", actual)) } // Test that fetching with no index makes an initial request with no index, but // then ensures all background refreshes have > 0. This ensures we don't end up // with any index 0 loops from background refreshed while also returning // immediately on the initial request if there is no data written to that table // yet. func TestCacheGet_noIndexSetsOne(t *testing.T) { t.Parallel() typ := &MockType{} typ.On("RegisterOptions").Return(RegisterOptions{ SupportsBlocking: true, Refresh: true, RefreshTimer: 0, QueryTimeout: 5 * time.Minute, }) defer typ.AssertExpectations(t) c := New(Options{}) c.RegisterType("t", typ) // Simulate "well behaved" RPC with no data yet but returning 1 { first := int32(1) typ.Static(FetchResult{Value: 0, Index: 1}, nil).Run(func(args mock.Arguments) { opts := args.Get(0).(FetchOptions) isFirst := atomic.SwapInt32(&first, 0) if isFirst == 1 { assert.Equal(t, uint64(0), opts.MinIndex) } else { assert.True(t, opts.MinIndex > 0, "minIndex > 0") } }) // Fetch resultCh := TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{Key: "hello"})) TestCacheGetChResult(t, resultCh, 0) // Sleep a bit so background refresh happens time.Sleep(100 * time.Millisecond) } // Same for "badly behaved" RPC that returns 0 index and no data { first := int32(1) typ.Static(FetchResult{Value: 0, Index: 0}, nil).Run(func(args mock.Arguments) { opts := args.Get(0).(FetchOptions) isFirst := atomic.SwapInt32(&first, 0) if isFirst == 1 { assert.Equal(t, uint64(0), opts.MinIndex) } else { assert.True(t, opts.MinIndex > 0, "minIndex > 0") } }) // Fetch resultCh := TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{Key: "hello"})) TestCacheGetChResult(t, resultCh, 0) // Sleep a bit so background refresh happens time.Sleep(100 * time.Millisecond) } } // Test that the backend fetch sets the proper timeout. func TestCacheGet_fetchTimeout(t *testing.T) { t.Parallel() require := require.New(t) typ := &MockType{} timeout := 10 * time.Minute typ.On("RegisterOptions").Return(RegisterOptions{ QueryTimeout: timeout, SupportsBlocking: true, }) defer typ.AssertExpectations(t) c := New(Options{}) // Register the type with a timeout c.RegisterType("t", typ) // Configure the type var actual time.Duration typ.Static(FetchResult{Value: 42}, nil).Times(1).Run(func(args mock.Arguments) { opts := args.Get(0).(FetchOptions) actual = opts.Timeout }) // Get, should fetch req := TestRequest(t, RequestInfo{Key: "hello"}) result, meta, err := c.Get(context.Background(), "t", req) require.NoError(err) require.Equal(42, result) require.False(meta.Hit) // Test the timeout require.Equal(timeout, actual) } // Test that entries expire func TestCacheGet_expire(t *testing.T) { t.Parallel() require := require.New(t) typ := &MockType{} typ.On("RegisterOptions").Return(RegisterOptions{ LastGetTTL: 400 * time.Millisecond, }) defer typ.AssertExpectations(t) c := New(Options{}) // Register the type with a timeout c.RegisterType("t", typ) // Configure the type typ.Static(FetchResult{Value: 42}, nil).Times(2) // Get, should fetch req := TestRequest(t, RequestInfo{Key: "hello"}) result, meta, err := c.Get(context.Background(), "t", req) require.NoError(err) require.Equal(42, result) require.False(meta.Hit) // Wait for a non-trivial amount of time to sanity check the age increases at // least this amount. Note that this is not a fudge for some timing-dependent // background work it's just ensuring a non-trivial time elapses between the // request above and below serilaly in this thread so short time is OK. time.Sleep(5 * time.Millisecond) // Get, should not fetch, verified via the mock assertions above req = TestRequest(t, RequestInfo{Key: "hello"}) result, meta, err = c.Get(context.Background(), "t", req) require.NoError(err) require.Equal(42, result) require.True(meta.Hit) require.True(meta.Age > 5*time.Millisecond) // Sleep for the expiry time.Sleep(500 * time.Millisecond) // Get, should fetch req = TestRequest(t, RequestInfo{Key: "hello"}) result, meta, err = c.Get(context.Background(), "t", req) require.NoError(err) require.Equal(42, result) require.False(meta.Hit) // Sleep a tiny bit just to let maybe some background calls happen // then verify that we still only got the one call time.Sleep(20 * time.Millisecond) typ.AssertExpectations(t) } // Test that entries reset their TTL on Get func TestCacheGet_expireResetGet(t *testing.T) { t.Parallel() require := require.New(t) typ := &MockType{} typ.On("RegisterOptions").Return(RegisterOptions{ LastGetTTL: 150 * time.Millisecond, }) defer typ.AssertExpectations(t) c := New(Options{}) // Register the type with a timeout c.RegisterType("t", typ) // Configure the type typ.Static(FetchResult{Value: 42}, nil).Times(2) // Get, should fetch req := TestRequest(t, RequestInfo{Key: "hello"}) result, meta, err := c.Get(context.Background(), "t", req) require.NoError(err) require.Equal(42, result) require.False(meta.Hit) // Fetch multiple times, where the total time is well beyond // the TTL. We should not trigger any fetches during this time. for i := 0; i < 5; i++ { // Sleep a bit time.Sleep(50 * time.Millisecond) // Get, should not fetch req = TestRequest(t, RequestInfo{Key: "hello"}) result, meta, err = c.Get(context.Background(), "t", req) require.NoError(err) require.Equal(42, result) require.True(meta.Hit) } time.Sleep(200 * time.Millisecond) // Get, should fetch req = TestRequest(t, RequestInfo{Key: "hello"}) result, meta, err = c.Get(context.Background(), "t", req) require.NoError(err) require.Equal(42, result) require.False(meta.Hit) // Sleep a tiny bit just to let maybe some background calls happen // then verify that we still only got the one call time.Sleep(20 * time.Millisecond) typ.AssertExpectations(t) } // Test a Get with a request that returns the same cache key across // two different "types" returns two separate results. func TestCacheGet_duplicateKeyDifferentType(t *testing.T) { t.Parallel() require := require.New(t) typ := TestType(t) defer typ.AssertExpectations(t) typ2 := TestType(t) defer typ2.AssertExpectations(t) c := New(Options{}) c.RegisterType("t", typ) c.RegisterType("t2", typ2) // Configure the types typ.Static(FetchResult{Value: 100}, nil) typ2.Static(FetchResult{Value: 200}, nil) // Get, should fetch req := TestRequest(t, RequestInfo{Key: "foo"}) result, meta, err := c.Get(context.Background(), "t", req) require.NoError(err) require.Equal(100, result) require.False(meta.Hit) // Get from t2 with same key, should fetch req = TestRequest(t, RequestInfo{Key: "foo"}) result, meta, err = c.Get(context.Background(), "t2", req) require.NoError(err) require.Equal(200, result) require.False(meta.Hit) // Get from t again with same key, should cache req = TestRequest(t, RequestInfo{Key: "foo"}) result, meta, err = c.Get(context.Background(), "t", req) require.NoError(err) require.Equal(100, result) require.True(meta.Hit) // Sleep a tiny bit just to let maybe some background calls happen // then verify that we still only got the one call time.Sleep(20 * time.Millisecond) typ.AssertExpectations(t) typ2.AssertExpectations(t) } // Test that Get partitions the caches based on DC so two equivalent requests // to different datacenters are automatically cached even if their keys are // the same. func TestCacheGet_partitionDC(t *testing.T) { t.Parallel() c := New(Options{}) c.RegisterType("t", &testPartitionType{}) // Perform multiple gets getCh1 := TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{ Datacenter: "dc1", Key: "hello"})) getCh2 := TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{ Datacenter: "dc9", Key: "hello"})) // Should return both! TestCacheGetChResult(t, getCh1, "dc1") TestCacheGetChResult(t, getCh2, "dc9") } // Test that Get partitions the caches based on token so two equivalent requests // with different ACL tokens do not return the same result. func TestCacheGet_partitionToken(t *testing.T) { t.Parallel() c := New(Options{}) c.RegisterType("t", &testPartitionType{}) // Perform multiple gets getCh1 := TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{ Token: "", Key: "hello"})) getCh2 := TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{ Token: "foo", Key: "hello"})) // Should return both! TestCacheGetChResult(t, getCh1, "") TestCacheGetChResult(t, getCh2, "foo") } // testPartitionType implements Type for testing that simply returns a value // comprised of the request DC and ACL token, used for testing cache // partitioning. type testPartitionType struct{} func (t *testPartitionType) Fetch(opts FetchOptions, r Request) (FetchResult, error) { info := r.CacheInfo() return FetchResult{ Value: fmt.Sprintf("%s%s", info.Datacenter, info.Token), }, nil } func (t *testPartitionType) RegisterOptions() RegisterOptions { return RegisterOptions{ SupportsBlocking: true, } } // Test that background refreshing reports correct Age in failure and happy // states. func TestCacheGet_refreshAge(t *testing.T) { t.Parallel() require := require.New(t) typ := &MockType{} typ.On("RegisterOptions").Return(RegisterOptions{ Refresh: true, RefreshTimer: 0, QueryTimeout: 5 * time.Minute, }) defer typ.AssertExpectations(t) c := New(Options{}) c.RegisterType("t", typ) // Configure the type var index, shouldFail uint64 typ.On("Fetch", mock.Anything, mock.Anything). Return(func(o FetchOptions, r Request) FetchResult { idx := atomic.LoadUint64(&index) if atomic.LoadUint64(&shouldFail) == 1 { return FetchResult{Value: nil, Index: idx} } if o.MinIndex == idx { // Simulate waiting for a new value time.Sleep(5 * time.Millisecond) } return FetchResult{Value: int(idx * 2), Index: idx} }, func(o FetchOptions, r Request) error { if atomic.LoadUint64(&shouldFail) == 1 { return errors.New("test error") } return nil }) // Set initial index/value atomic.StoreUint64(&index, 4) // Fetch resultCh := TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{Key: "hello"})) TestCacheGetChResult(t, resultCh, 8) { // Wait a few milliseconds after initial fetch to check age is not reporting // actual age. time.Sleep(2 * time.Millisecond) // Fetch again, non-blocking result, meta, err := c.Get(context.Background(), "t", TestRequest(t, RequestInfo{Key: "hello"})) require.NoError(err) require.Equal(8, result) require.True(meta.Hit) // Age should be zero since background refresh was "active" require.Equal(time.Duration(0), meta.Age) } // Now fail the next background sync atomic.StoreUint64(&shouldFail, 1) // Wait until the current request times out and starts failing. The request // should take a maximum of 5ms to return but give it some headroom to allow // it to finish 5ms sleep, unblock and next background request to be attemoted // and fail and state updated in noisy CI... We might want to retry if this is // still flaky but see if a longer wait is sufficient for now. time.Sleep(50 * time.Millisecond) var lastAge time.Duration { result, meta, err := c.Get(context.Background(), "t", TestRequest(t, RequestInfo{Key: "hello"})) require.NoError(err) require.Equal(8, result) require.True(meta.Hit) // Age should be non-zero since background refresh was "active" require.True(meta.Age > 0) lastAge = meta.Age } // Wait a bit longer - age should increase by at least this much time.Sleep(5 * time.Millisecond) { result, meta, err := c.Get(context.Background(), "t", TestRequest(t, RequestInfo{Key: "hello"})) require.NoError(err) require.Equal(8, result) require.True(meta.Hit) require.True(meta.Age > (lastAge + (1 * time.Millisecond))) } // Now unfail the background refresh atomic.StoreUint64(&shouldFail, 0) // And update the data so we can see when the background task is working again // (won't be immediate due to backoff on the errors). atomic.AddUint64(&index, 1) t0 := time.Now() timeout := true // Allow up to 5 seconds since the error backoff is likely to have kicked in // and causes this to take different amounts of time depending on how quickly // the test thread got down here relative to the failures. for attempts := 0; attempts < 50; attempts++ { time.Sleep(100 * time.Millisecond) result, meta, err := c.Get(context.Background(), "t", TestRequest(t, RequestInfo{Key: "hello"})) // Should never error even if background is failing as we have cached value require.NoError(err) require.True(meta.Hit) // Got the new value! if result == 10 { // Age should be zero since background refresh is "active" again t.Logf("Succeeded after %d attempts", attempts) require.Equal(time.Duration(0), meta.Age) timeout = false break } } require.False(timeout, "failed to observe update after %s", time.Since(t0)) } func TestCacheGet_nonRefreshAge(t *testing.T) { t.Parallel() require := require.New(t) typ := &MockType{} typ.On("RegisterOptions").Return(RegisterOptions{ Refresh: false, LastGetTTL: 100 * time.Millisecond, }) defer typ.AssertExpectations(t) c := New(Options{}) c.RegisterType("t", typ) // Configure the type var index uint64 typ.On("Fetch", mock.Anything, mock.Anything). Return(func(o FetchOptions, r Request) FetchResult { idx := atomic.LoadUint64(&index) return FetchResult{Value: int(idx * 2), Index: idx} }, nil) // Set initial index/value atomic.StoreUint64(&index, 4) // Fetch resultCh := TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{Key: "hello"})) TestCacheGetChResult(t, resultCh, 8) var lastAge time.Duration { // Wait a few milliseconds after initial fetch to check age IS reporting // actual age. time.Sleep(5 * time.Millisecond) // Fetch again, non-blocking result, meta, err := c.Get(context.Background(), "t", TestRequest(t, RequestInfo{Key: "hello"})) require.NoError(err) require.Equal(8, result) require.True(meta.Hit) require.True(meta.Age > (5 * time.Millisecond)) lastAge = meta.Age } // Wait for expiry time.Sleep(200 * time.Millisecond) { result, meta, err := c.Get(context.Background(), "t", TestRequest(t, RequestInfo{Key: "hello"})) require.NoError(err) require.Equal(8, result) require.False(meta.Hit) // Age should smaller again require.True(meta.Age < lastAge) } { // Wait for a non-trivial amount of time to sanity check the age increases at // least this amount. Note that this is not a fudge for some timing-dependent // background work it's just ensuring a non-trivial time elapses between the // request above and below serilaly in this thread so short time is OK. time.Sleep(5 * time.Millisecond) // Fetch again, non-blocking result, meta, err := c.Get(context.Background(), "t", TestRequest(t, RequestInfo{Key: "hello"})) require.NoError(err) require.Equal(8, result) require.True(meta.Hit) require.True(meta.Age > (5 * time.Millisecond)) lastAge = meta.Age } // Now verify that setting MaxAge results in cache invalidation { result, meta, err := c.Get(context.Background(), "t", TestRequest(t, RequestInfo{ Key: "hello", MaxAge: 1 * time.Millisecond, })) require.NoError(err) require.Equal(8, result) require.False(meta.Hit) // Age should smaller again require.True(meta.Age < lastAge) } } func TestCacheGet_nonBlockingType(t *testing.T) { t.Parallel() typ := TestTypeNonBlocking(t) c := New(Options{}) c.RegisterType("t", typ) // Configure the type typ.Static(FetchResult{Value: 42, Index: 1}, nil).Once() typ.Static(FetchResult{Value: 43, Index: 2}, nil).Twice(). Run(func(args mock.Arguments) { opts := args.Get(0).(FetchOptions) // MinIndex should never be set for a non-blocking type. require.Equal(t, uint64(0), opts.MinIndex) }) require := require.New(t) // Get, should fetch req := TestRequest(t, RequestInfo{Key: "hello"}) result, meta, err := c.Get(context.Background(), "t", req) require.NoError(err) require.Equal(42, result) require.False(meta.Hit) // Get, should not fetch since we have a cached value req = TestRequest(t, RequestInfo{Key: "hello"}) result, meta, err = c.Get(context.Background(), "t", req) require.NoError(err) require.Equal(42, result) require.True(meta.Hit) // Get, should not attempt to fetch with blocking even if requested. The // assertions below about the value being the same combined with the fact the // mock will only return that value on first call suffice to show that // blocking request is not being attempted. req = TestRequest(t, RequestInfo{ Key: "hello", MinIndex: 1, Timeout: 10 * time.Minute, }) result, meta, err = c.Get(context.Background(), "t", req) require.NoError(err) require.Equal(42, result) require.True(meta.Hit) time.Sleep(10 * time.Millisecond) // Get with a max age should fetch again req = TestRequest(t, RequestInfo{Key: "hello", MaxAge: 5 * time.Millisecond}) result, meta, err = c.Get(context.Background(), "t", req) require.NoError(err) require.Equal(43, result) require.False(meta.Hit) // Get with a must revalidate should fetch again even without a delay. req = TestRequest(t, RequestInfo{Key: "hello", MustRevalidate: true}) result, meta, err = c.Get(context.Background(), "t", req) require.NoError(err) require.Equal(43, result) require.False(meta.Hit) // Sleep a tiny bit just to let maybe some background calls happen // then verify that we still only got the one call time.Sleep(20 * time.Millisecond) typ.AssertExpectations(t) } // TestCacheThrottle checks the assumptions for the cache throttling. It sets // up a cache with Options{EntryFetchRate: 10.0, EntryFetchMaxBurst: 1}, which // allows for 10req/s, or one request every 100ms. // It configures two different cache types with each 3 updates. Each type has // its own rate limiter which starts initially full, and we expect the // following requests when creating blocking queries against both waiting for // the third update: // at ~0ms: typ1 and typ2 receive first value and are blocked until // ~100ms: typ1 and typ2 receive second value and are blocked until // ~200ms: typ1 and typ2 receive third value which we check // // This test will verify waiting with a blocking query for the last update will // block for 190ms and only afterwards have the expected result. // It demonstrates the ratelimiting waits for the expected amount of time and // also that each type has its own ratelimiter, because results for both types // are arriving at similar times, which wouldn't be the case if they use a // shared limiter. func TestCacheThrottle(t *testing.T) { t.Parallel() typ1 := TestType(t) typ2 := TestType(t) defer typ1.AssertExpectations(t) defer typ2.AssertExpectations(t) c := New(Options{EntryFetchRate: 10.0, EntryFetchMaxBurst: 1}) c.RegisterType("t1", typ1) c.RegisterType("t2", typ2) // Configure the type typ1.Static(FetchResult{Value: 1, Index: 4}, nil).Once() typ1.Static(FetchResult{Value: 12, Index: 5}, nil).Once() typ1.Static(FetchResult{Value: 42, Index: 6}, nil).Once() typ2.Static(FetchResult{Value: 1, Index: 4}, nil).Once() typ2.Static(FetchResult{Value: 12, Index: 5}, nil).Once() typ2.Static(FetchResult{Value: 43, Index: 6}, nil).Once() result1Ch := TestCacheGetCh(t, c, "t1", TestRequest(t, RequestInfo{ Key: "hello1", MinIndex: 5})) result2Ch := TestCacheGetCh(t, c, "t2", TestRequest(t, RequestInfo{ Key: "hello2", MinIndex: 5})) select { case <-result1Ch: t.Fatal("result1Ch should block") case <-result2Ch: t.Fatal("result2Ch should block") case <-time.After(190 * time.Millisecond): } after := time.After(30 * time.Millisecond) var res1, res2 bool OUT: for { select { case result := <-result1Ch: require.Equal(t, 42, result) res1 = true case result := <-result2Ch: require.Equal(t, 43, result) res2 = true case <-after: t.Fatal("shouldn't block that long") } if res1 && res2 { break OUT } } }