[query] Add per query enforcer to graphite path (m3db#1459)

src/query/executor/engine.go

@@ -143,10 +143,7 @@ func (e *Engine) ExecuteExpr(
  defer close(results)
 
  perQueryEnforcer := e.globalEnforcer.Child(qcost.QueryLevel)
- defer func() {
- perQueryEnforcer.Close()
- }()
-
+ defer perQueryEnforcer.Close()
  req := newRequest(e, params)
 
  nodes, edges, err := req.compile(ctx, parser)

src/query/graphite/storage/m3_wrapper.go

@@ -139,7 +139,10 @@ func (s *m3WrappedStore) FetchByQuery(
  m3ctx, cancel := context.WithTimeout(ctx.RequestContext(), opts.Timeout)
  defer cancel()
  fetchOptions := storage.NewFetchOptions()
- fetchOptions.Enforcer = s.enforcer
+ perQueryEnforcer := s.enforcer.Child(cost.QueryLevel)
+ defer perQueryEnforcer.Close()
+
+ fetchOptions.Enforcer = perQueryEnforcer
  fetchOptions.FanoutOptions = &storage.FanoutOptions{
  FanoutUnaggregated: storage.FanoutForceDisable,
  FanoutAggregated: storage.FanoutDefault,

src/query/graphite/storage/m3_wrapper_test.go

@@ -33,8 +33,8 @@ import (
  "github.com/m3db/m3/src/query/storage"
  "github.com/m3db/m3/src/query/storage/mock"
  m3ts "github.com/m3db/m3/src/query/ts"
- xcost "github.com/m3db/m3/src/x/cost"
 
+ "github.com/golang/mock/gomock"
  "github.com/stretchr/testify/assert"
  "github.com/stretchr/testify/require"
 )
@@ -139,9 +139,15 @@ func TestFetchByQuery(t *testing.T) {
  }
 
  store.SetFetchResult(&storage.FetchResult{SeriesList: seriesList}, nil)
- enforcers := []xcost.Enforcer{xcost.NewEnforcer(nil, nil, nil)}
- enforcer, err := cost.NewChainedEnforcer("name", enforcers)
- require.NoError(t, err)
+
+ ctrl := gomock.NewController(t)
+ defer ctrl.Finish()
+ childEnforcer := cost.NewMockChainedEnforcer(ctrl)
+ childEnforcer.EXPECT().Close()
+
+ enforcer := cost.NewMockChainedEnforcer(ctrl)
+ enforcer.EXPECT().Child(cost.QueryLevel).Return(childEnforcer).MinTimes(1)
+
  wrapper := NewM3WrappedStorage(store, enforcer)
  ctx := xctx.New()
  ctx.SetRequestContext(context.TODO())
@@ -162,6 +168,6 @@ func TestFetchByQuery(t *testing.T) {
  assert.Equal(t, "a", series.Name())
  assert.Equal(t, []float64{3, 3, 3}, series.SafeValues())
 
- // NB: ensure the fetch was called with enforcer propagated correctly
- assert.Equal(t, enforcer, store.LastFetchOptions().Enforcer)
+ // NB: ensure the fetch was called with the base enforcer's child correctly
+ assert.Equal(t, childEnforcer, store.LastFetchOptions().Enforcer)
 }