bugfix: remove config check and fix memory leak in traffic-tag (#1435)

plugins/wasm-go/extensions/traffic-tag/content.go

@@ -26,10 +26,6 @@ import (
 )
 
 func onContentRequestHeaders(conditionGroups []ConditionGroup, log wrapper.Log) bool {
-	if len(conditionGroups) == 0 {
-		return false
-	}
-
 	for _, cg := range conditionGroups {
 		if matchCondition(&cg, log) {
 			addTagHeader(cg.HeaderName, cg.HeaderValue, log)

plugins/wasm-go/extensions/traffic-tag/main.go

@@ -16,6 +16,7 @@ package main
 
 import (
 	"math/rand"
+	"strings"
 
 	"github.com/alibaba/higress/plugins/wasm-go/pkg/wrapper"
 	"github.com/higress-group/proxy-wasm-go-sdk/proxywasm/types"
@@ -60,7 +61,6 @@ type TrafficTagConfig struct {
 	WeightGroups    []WeightGroup    `json:"weightGroups,omitempty"`
 	DefaultTagKey   string           `json:"defaultTagKey,omitempty"`
 	DefaultTagVal   string           `json:"defaultTagVal,omitempty"`
-	randGen         *rand.Rand
 }
 
 type ConditionGroup struct {
@@ -93,8 +93,11 @@ func main() {
 }
 
 func parseConfig(json gjson.Result, config *TrafficTagConfig, log wrapper.Log) error {
-	if err := jsonValidate(json, log); err != nil {
-		return err
+
+	jsonStr := strings.TrimSpace(json.Raw)
+	if jsonStr == "{}" || jsonStr == "" {
+		log.Error("plugin config is empty")
+		return nil
 	}
 
 	err := parseContentConfig(json, config, log)
@@ -106,7 +109,17 @@ func parseConfig(json gjson.Result, config *TrafficTagConfig, log wrapper.Log) e
 }
 
 func onHttpRequestHeaders(ctx wrapper.HttpContext, config TrafficTagConfig, log wrapper.Log) types.Action {
-	if add := (onContentRequestHeaders(config.ConditionGroups, log) || onWeightRequestHeaders(config.WeightGroups, config.randGen, log)); !add {
+
+	add := false
+	if len(config.ConditionGroups) != 0 {
+		add = add || onContentRequestHeaders(config.ConditionGroups, log)
+	}
+
+	if !add && len(config.WeightGroups) != 0 {
+		add = add || onWeightRequestHeaders(config.WeightGroups, rand.Uint64(), log)
+	}
+
+	if !add {
 		setDefaultTag(config.DefaultTagKey, config.DefaultTagVal, log)
 	}
 

plugins/wasm-go/extensions/traffic-tag/parse.go

@@ -17,10 +17,8 @@ package main
 import (
 	"errors"
 	"fmt"
-	"math/rand"
 	"strconv"
 	"strings"
-	"time"
 
 	"github.com/higress-group/proxy-wasm-go-sdk/proxywasm"
 	regexp "github.com/wasilibs/go-re2"
@@ -85,7 +83,6 @@ func parseWeightConfig(json gjson.Result, config *TrafficTagConfig, log wrapper.
 	var parseError error
 	var accumulatedWeight int64
 	config.WeightGroups = []WeightGroup{}
-	config.randGen = rand.New(rand.NewSource(time.Now().UnixNano()))
 
 	// parse default tag key and value
 	if k, v := json.Get(DefaultTagKey), json.Get(DefaultTagVal); k.Exists() && v.Exists() {

plugins/wasm-go/extensions/traffic-tag/utils.go

@@ -15,14 +15,12 @@
 package main
 
 import (
-	"errors"
 	"fmt"
 	"net/url"
 	"strings"
 
 	"github.com/alibaba/higress/plugins/wasm-go/pkg/wrapper"
 	"github.com/higress-group/proxy-wasm-go-sdk/proxywasm"
-	"github.com/tidwall/gjson"
 )
 
 func setDefaultTag(k string, v string, log wrapper.Log) {
@@ -75,23 +73,3 @@ func addTagHeader(key string, value string, log wrapper.Log) {
 	}
 	log.Infof("ADD HEADER: %s, value: %s", key, value)
 }
-
-func jsonValidate(json gjson.Result, log wrapper.Log) error {
-	if !json.Exists() {
-		log.Error("plugin config is missing in JSON")
-		return errors.New("plugin config is missing in JSON")
-	}
-
-	jsonStr := strings.TrimSpace(json.Raw)
-	if jsonStr == "{}" || jsonStr == "" {
-		log.Error("plugin config is empty")
-		return errors.New("plugin config is empty")
-	}
-
-	if !gjson.Valid(json.Raw) {
-		log.Error("plugin config is invalid JSON")
-		return errors.New("plugin config is invalid JSON")
-	}
-
-	return nil
-}

plugins/wasm-go/extensions/traffic-tag/weight.go

@@ -15,16 +15,11 @@
 package main
 
 import (
-	"math/rand"
-
 	"github.com/alibaba/higress/plugins/wasm-go/pkg/wrapper"
 )
 
-func onWeightRequestHeaders(weightGroups []WeightGroup, randGen *rand.Rand, log wrapper.Log) bool {
-	if len(weightGroups) == 0 {
-		return false
-	}
-	randomValue := randGen.Uint64() % TotalWeight
+func onWeightRequestHeaders(weightGroups []WeightGroup, randomNum uint64, log wrapper.Log) bool {
+	randomValue := randomNum % TotalWeight
 	log.Debugf("random value for weighted headers : %d", randomValue)
 	// CDF
 	for _, wg := range weightGroups {