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package throttled_test
import (
"testing"
"time"
"github.com/throttled/throttled"
"github.com/throttled/throttled/store/memstore"
)
const deniedStatus = 429
type testStore struct {
store throttled.GCRAStore
clock time.Time
failUpdates bool
}
func (ts *testStore) GetWithTime(key string) (int64, time.Time, error) {
v, _, e := ts.store.GetWithTime(key)
return v, ts.clock, e
}
func (ts *testStore) SetIfNotExistsWithTTL(key string, value int64, ttl time.Duration) (bool, error) {
if ts.failUpdates {
return false, nil
}
return ts.store.SetIfNotExistsWithTTL(key, value, ttl)
}
func (ts *testStore) CompareAndSwapWithTTL(key string, old, new int64, ttl time.Duration) (bool, error) {
if ts.failUpdates {
return false, nil
}
return ts.store.CompareAndSwapWithTTL(key, old, new, ttl)
}
func TestRateLimit(t *testing.T) {
limit := 5
rq := throttled.RateQuota{throttled.PerSec(1), limit - 1}
start := time.Unix(0, 0)
cases := []struct {
now time.Time
volume, remaining int
reset, retry time.Duration
limited bool
}{
// You can never make a request larger than the maximum
0: {start, 6, 5, 0, -1, true},
// Rate limit normal requests appropriately
1: {start, 1, 4, time.Second, -1, false},
2: {start, 1, 3, 2 * time.Second, -1, false},
3: {start, 1, 2, 3 * time.Second, -1, false},
4: {start, 1, 1, 4 * time.Second, -1, false},
5: {start, 1, 0, 5 * time.Second, -1, false},
6: {start, 1, 0, 5 * time.Second, time.Second, true},
7: {start.Add(3000 * time.Millisecond), 1, 2, 3000 * time.Millisecond, -1, false},
8: {start.Add(3100 * time.Millisecond), 1, 1, 3900 * time.Millisecond, -1, false},
9: {start.Add(4000 * time.Millisecond), 1, 1, 4000 * time.Millisecond, -1, false},
10: {start.Add(8000 * time.Millisecond), 1, 4, 1000 * time.Millisecond, -1, false},
11: {start.Add(9500 * time.Millisecond), 1, 4, 1000 * time.Millisecond, -1, false},
// Zero-volume request just peeks at the state
12: {start.Add(9500 * time.Millisecond), 0, 4, time.Second, -1, false},
// High-volume request uses up more of the limit
13: {start.Add(9500 * time.Millisecond), 2, 2, 3 * time.Second, -1, false},
// Large requests cannot exceed limits
14: {start.Add(9500 * time.Millisecond), 5, 2, 3 * time.Second, 3 * time.Second, true},
}
mst, err := memstore.New(0)
if err != nil {
t.Fatal(err)
}
st := testStore{store: mst}
rl, err := throttled.NewGCRARateLimiter(&st, rq)
if err != nil {
t.Fatal(err)
}
// Start the server
for i, c := range cases {
st.clock = c.now
limited, context, err := rl.RateLimit("foo", c.volume)
if err != nil {
t.Fatalf("%d: %#v", i, err)
}
if limited != c.limited {
t.Errorf("%d: expected Limited to be %t but got %t", i, c.limited, limited)
}
if have, want := context.Limit, limit; have != want {
t.Errorf("%d: expected Limit to be %d but got %d", i, want, have)
}
if have, want := context.Remaining, c.remaining; have != want {
t.Errorf("%d: expected Remaining to be %d but got %d", i, want, have)
}
if have, want := context.ResetAfter, c.reset; have != want {
t.Errorf("%d: expected ResetAfter to be %s but got %s", i, want, have)
}
if have, want := context.RetryAfter, c.retry; have != want {
t.Errorf("%d: expected RetryAfter to be %d but got %d", i, want, have)
}
}
}
func TestRateLimitUpdateFailures(t *testing.T) {
rq := throttled.RateQuota{throttled.PerSec(1), 1}
mst, err := memstore.New(0)
if err != nil {
t.Fatal(err)
}
st := testStore{store: mst, failUpdates: true}
rl, err := throttled.NewGCRARateLimiter(&st, rq)
if err != nil {
t.Fatal(err)
}
if _, _, err := rl.RateLimit("foo", 1); err == nil {
t.Error("Expected limiting to fail when store updates fail")
}
}
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