consul/agent/cache/cache_test.go

677 lines
19 KiB
Go

package cache
import (
"fmt"
"sort"
"sync"
"sync/atomic"
"testing"
"time"
"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 := TestCache(t)
c.RegisterType("t", typ, nil)
// Configure the type
typ.Static(FetchResult{Value: 42}, nil).Times(1)
// Get, should fetch
req := TestRequest(t, RequestInfo{Key: "hello"})
result, err := c.Get("t", req)
require.NoError(err)
require.Equal(42, result)
// Get, should not fetch since we already have a satisfying value
result, err = c.Get("t", req)
require.NoError(err)
require.Equal(42, result)
// 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 := TestCache(t)
c.RegisterType("t", typ, nil)
// Configure the type
fetcherr := fmt.Errorf("error")
typ.Static(FetchResult{}, fetcherr).Times(2)
// Get, should fetch
req := TestRequest(t, RequestInfo{Key: "hello"})
result, err := c.Get("t", req)
require.Error(err)
require.Nil(result)
// Get, should fetch again since our last fetch was an error
result, err = c.Get("t", req)
require.Error(err)
require.Nil(result)
// 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 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 := TestCache(t)
c.RegisterType("t", typ, nil)
// Configure the type
typ.Static(FetchResult{Value: 42}, nil).Times(2)
// Get, should fetch
req := TestRequest(t, RequestInfo{Key: ""})
result, err := c.Get("t", req)
require.NoError(err)
require.Equal(42, result)
// Get, should not fetch since we already have a satisfying value
result, err = c.Get("t", req)
require.NoError(err)
require.Equal(42, result)
// 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 := TestCache(t)
c.RegisterType("t", typ, nil)
// 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 := TestCache(t)
c.RegisterType("t", typ, nil)
// 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 := TestCache(t)
c.RegisterType("t", typ, nil)
// 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)
}
// 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 := TestCache(t)
c.RegisterType("t", typ, nil)
// 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 := TestCache(t)
c.RegisterType("t", typ, nil)
// 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 := TestCache(t)
c.RegisterType("t", typ, nil)
// Configure the type
typ.Static(FetchResult{Value: 42, Index: 1}, nil).Times(1)
typ.Static(FetchResult{Value: nil}, nil)
// Get, should fetch
req := TestRequest(t, RequestInfo{Key: "hello"})
result, err := c.Get("t", req)
require.NoError(err)
require.Equal(42, result)
// Get, should not fetch since we already have a satisfying value
req = TestRequest(t, RequestInfo{
Key: "hello", MinIndex: 1, Timeout: 100 * time.Millisecond})
result, err = c.Get("t", req)
require.NoError(err)
require.Equal(42, result)
// 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 := TestType(t)
defer typ.AssertExpectations(t)
c := TestCache(t)
c.RegisterType("t", typ, &RegisterOptions{
Refresh: true,
RefreshTimer: 100 * time.Millisecond,
RefreshTimeout: 5 * time.Minute,
})
// 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 := TestType(t)
defer typ.AssertExpectations(t)
c := TestCache(t)
c.RegisterType("t", typ, &RegisterOptions{
Refresh: true,
RefreshTimer: 0 * time.Millisecond,
RefreshTimeout: 5 * time.Minute,
})
// 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 := TestType(t)
defer typ.AssertExpectations(t)
c := TestCache(t)
c.RegisterType("t", typ, &RegisterOptions{
Refresh: true,
RefreshTimer: 0,
RefreshTimeout: 5 * time.Minute,
})
// 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 fetching with no index actually sets to index to one, including
// for background refreshes. This ensures we don't end up with any index 0
// loops.
func TestCacheGet_noIndexSetsOne(t *testing.T) {
t.Parallel()
typ := TestType(t)
defer typ.AssertExpectations(t)
c := TestCache(t)
c.RegisterType("t", typ, &RegisterOptions{
Refresh: true,
RefreshTimer: 0,
RefreshTimeout: 5 * time.Minute,
})
// Configure the type
fetchErr := fmt.Errorf("test fetch error")
typ.Static(FetchResult{Value: 42, Index: 0}, fetchErr).Run(func(args mock.Arguments) {
opts := args.Get(0).(FetchOptions)
assert.True(t, opts.MinIndex > 0, "minIndex > 0")
})
// Fetch
resultCh := TestCacheGetCh(t, c, "t", TestRequest(t, RequestInfo{Key: "hello"}))
TestCacheGetChResult(t, resultCh, 42)
// 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 := TestType(t)
defer typ.AssertExpectations(t)
c := TestCache(t)
// Register the type with a timeout
timeout := 10 * time.Minute
c.RegisterType("t", typ, &RegisterOptions{
RefreshTimeout: timeout,
})
// 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, err := c.Get("t", req)
require.NoError(err)
require.Equal(42, result)
// Test the timeout
require.Equal(timeout, actual)
}
// Test that entries expire
func TestCacheGet_expire(t *testing.T) {
t.Parallel()
require := require.New(t)
typ := TestType(t)
defer typ.AssertExpectations(t)
c := TestCache(t)
// Register the type with a timeout
c.RegisterType("t", typ, &RegisterOptions{
LastGetTTL: 400 * time.Millisecond,
})
// Configure the type
typ.Static(FetchResult{Value: 42}, nil).Times(2)
// Get, should fetch
req := TestRequest(t, RequestInfo{Key: "hello"})
result, err := c.Get("t", req)
require.NoError(err)
require.Equal(42, result)
// Get, should not fetch, verified via the mock assertions above
hits := c.Hits()
req = TestRequest(t, RequestInfo{Key: "hello"})
result, err = c.Get("t", req)
require.NoError(err)
require.Equal(42, result)
require.Equal(hits+1, c.Hits())
// Sleep for the expiry
time.Sleep(500 * time.Millisecond)
// Get, should fetch
req = TestRequest(t, RequestInfo{Key: "hello"})
result, err = c.Get("t", req)
require.NoError(err)
require.Equal(42, result)
// 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 := TestType(t)
defer typ.AssertExpectations(t)
c := TestCache(t)
// Register the type with a timeout
c.RegisterType("t", typ, &RegisterOptions{
LastGetTTL: 150 * time.Millisecond,
})
// Configure the type
typ.Static(FetchResult{Value: 42}, nil).Times(2)
// Get, should fetch
req := TestRequest(t, RequestInfo{Key: "hello"})
result, err := c.Get("t", req)
require.NoError(err)
require.Equal(42, result)
// 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, err = c.Get("t", req)
require.NoError(err)
require.Equal(42, result)
}
time.Sleep(200 * time.Millisecond)
// Get, should fetch
req = TestRequest(t, RequestInfo{Key: "hello"})
result, err = c.Get("t", req)
require.NoError(err)
require.Equal(42, result)
// 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 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 := TestCache(t)
c.RegisterType("t", &testPartitionType{}, nil)
// 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 := TestCache(t)
c.RegisterType("t", &testPartitionType{}, nil)
// 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
}