Add throttle limit distribution empty ratios support (#747)

* Add throttle limit distribution empty ratios support

* Update CI

* Fix review comments

Author: kirillov6

.github/workflows/ci.yml

@@ -34,15 +34,13 @@ jobs:
         env:
           GOFLAGS: ${{ matrix.flags }}
           LOG_LEVEL: error
-        run: go test -coverprofile=profile.out -covermode=atomic -v -coverpkg=./... ./...
+        run: go test -coverprofile=profile${{ matrix.flags }}.out -covermode=atomic -v -coverpkg=./... ./...
 
       - name: Upload artifact
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
-          name: coverage
-          path: |
-            profile.out
-            profile_race.out
+          name: coverage${{ matrix.flags }}
+          path: profile${{ matrix.flags }}.out
           if-no-files-found: error
           retention-days: 1
 
@@ -75,15 +73,13 @@ jobs:
         env:
           GOFLAGS: ${{ matrix.flags }}
           LOG_LEVEL: error
-        run: go test ./e2e -coverprofile=profile_e2e.out -covermode=atomic -tags=e2e_new -timeout=3m -coverpkg=./...
+        run: go test ./e2e -coverprofile=profile-e2e${{ matrix.flags }}.out -covermode=atomic -tags=e2e_new -timeout=3m -coverpkg=./...
 
       - name: Upload artifact
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
-          name: coverage
-          path: |
-            profile_e2e.out
-            profile_e2e_race.out
+          name: coverage-e2e${{ matrix.flags }}
+          path: profile-e2e${{ matrix.flags }}.out
           if-no-files-found: error
           retention-days: 1
 
@@ -97,14 +93,15 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Download artifact
-        uses: actions/download-artifact@v3
+        uses: actions/download-artifact@v4
         with:
-          name: coverage
+          pattern: coverage*
+          merge-multiple: true
 
       - name: Send coverage
         uses: codecov/codecov-action@v3
         with:
-          files: profile.out, profile_race.out, profile_e2e.out, profile_e2e_race.out,
+          files: profile.out, profile-race.out, profile-e2e.out, profile-e2e-race.out,
 
   lint:
     runs-on: ubuntu-latest

plugin/action/throttle/distribution.go

@@ -40,8 +40,12 @@ func parseLimitDistribution(c limitDistributionCfg, totalLimit int64) (limitDist
 	if c.Field == "" {
 		return limitDistributions{}, nil
 	}
+
 	if len(c.Ratios) == 0 {
-		return limitDistributions{}, errors.New("empty 'ratios'")
+		return limitDistributions{
+			field:   cfg.ParseFieldSelector(c.Field),
+			enabled: c.Enabled,
+		}, nil
 	}
 
 	ld := limitDistributions{
@@ -103,7 +107,7 @@ type limitDistributions struct {
 }
 
 func (ld *limitDistributions) isEnabled() bool {
-	return ld.enabled
+	return ld.enabled && ld.size() > 0
 }
 
 func (ld *limitDistributions) size() int {

plugin/action/throttle/distribution_test.go

@@ -21,19 +21,20 @@ func Test_parseLimitDistribution(t *testing.T) {
 		wantErr bool
 	}{
 		{
-			name: "empty_cfg",
+			name: "empty",
 			cfg:  limitDistributionCfg{},
 			want: limitDistributions{},
 		},
 		{
-			name: "valid_cfg",
+			name: "valid_enabled",
 			cfg: limitDistributionCfg{
 				Field: field,
 				Ratios: []limitDistributionRatio{
 					{Ratio: 0.5, Values: []string{"error"}},
 					{Ratio: 0.35, Values: []string{"warn", "info"}},
 					{Ratio: 0.15, Values: []string{"debug"}},
 				},
+				Enabled: true,
 			},
 			totalLimit: 100,
 			want: limitDistributions{
@@ -48,10 +49,38 @@ func Test_parseLimitDistribution(t *testing.T) {
 					"warn":  1, "info": 1,
 					"debug": 2,
 				},
+				enabled: true,
 			},
 		},
 		{
-			name: "valid_cfg_with_def",
+			name: "valid_disabled",
+			cfg: limitDistributionCfg{
+				Field: field,
+				Ratios: []limitDistributionRatio{
+					{Ratio: 0.5, Values: []string{"error"}},
+					{Ratio: 0.35, Values: []string{"warn", "info"}},
+					{Ratio: 0.15, Values: []string{"debug"}},
+				},
+				Enabled: false,
+			},
+			totalLimit: 100,
+			want: limitDistributions{
+				field: fieldSlice,
+				distributions: []complexDistribution{
+					{ratio: 0.5, limit: 50},
+					{ratio: 0.35, limit: 35},
+					{ratio: 0.15, limit: 15},
+				},
+				idxByKey: map[string]int{
+					"error": 0,
+					"warn":  1, "info": 1,
+					"debug": 2,
+				},
+				enabled: false,
+			},
+		},
+		{
+			name: "valid_with_def",
 			cfg: limitDistributionCfg{
 				Field: field,
 				Ratios: []limitDistributionRatio{
@@ -80,11 +109,16 @@ func Test_parseLimitDistribution(t *testing.T) {
 			},
 		},
 		{
-			name: "err_empty_ratios",
+			name: "valid_empty_ratios",
 			cfg: limitDistributionCfg{
-				Field: field,
+				Field:   field,
+				Enabled: true,
+			},
+			totalLimit: 100,
+			want: limitDistributions{
+				field:   fieldSlice,
+				enabled: true,
 			},
-			wantErr: true,
 		},
 		{
 			name: "err_invalid_ratio1",
@@ -152,8 +186,9 @@ func Test_parseLimitDistribution(t *testing.T) {
 			}
 
 			require.Equal(t, tt.want.field, ld.field, "wrong field")
-			require.Equal(t, tt.want.defDistribution, ld.defDistribution, "wrong defPriority")
-			require.Equal(t, true, slices.Equal(tt.want.distributions, ld.distributions), "wrong priorities")
+			require.Equal(t, tt.want.defDistribution, ld.defDistribution, "wrong defDistribution")
+			require.Equal(t, tt.want.enabled, ld.enabled, "wrong enabled")
+			require.True(t, slices.Equal(tt.want.distributions, ld.distributions), "wrong distributions size")
 			require.Equal(t, len(tt.want.idxByKey), len(ld.idxByKey), "wrong idxByKey size")
 			for k, v := range ld.idxByKey {
 				require.Equal(t, tt.want.idxByKey[k], v, fmt.Sprintf("wrong value in idxByKey with key %q", k))