反向WS事件过滤器

global/filter.go

@@ -0,0 +1,248 @@
+package global
+
+import (
+	"bytes"
+	"github.com/buger/jsonparser"
+	log "github.com/sirupsen/logrus"
+	"io/ioutil"
+	"regexp"
+	"sync"
+)
+
+type Filter interface {
+	Eval(payload []byte) bool
+}
+
+type OperationNode struct {
+	key string
+	filter Filter
+}
+
+type NotOperator struct {
+	operand_ Filter
+}
+
+func notOperatorConstruct(argument []byte) *NotOperator {
+	op := new(NotOperator)
+	op.operand_ = GetOperatorFactory().Generate("and", argument)
+	return op
+}
+
+func (notOperator NotOperator) Eval(payload []byte) bool {
+	log.Debug("not "+string(payload))
+	return !(notOperator.operand_).Eval(payload)
+}
+
+type AndOperator struct {
+	operands []OperationNode
+}
+
+func andOperatorConstruct(argument []byte) *AndOperator {
+	op := new(AndOperator)
+	_ = jsonparser.ObjectEach(argument, func(key []byte, value []byte, dataType jsonparser.ValueType, offset int) error {
+		if key[0] == '.' {
+			// is an operator
+			//   ".foo": {
+			//       "bar": "baz"
+			//   }
+			opKey := string(key[1:])
+			op.operands = append(op.operands, OperationNode{"", GetOperatorFactory().Generate(opKey, value)})
+		} else if value[0] == '{' {
+			// is an normal key with an object as the value
+			//   "foo": {
+			//       ".bar": "baz"
+			//   }
+			opKey := string(key)
+			op.operands = append(op.operands, OperationNode{opKey, GetOperatorFactory().Generate("and", value)})
+		} else {
+			// is an normal key with a non-object as the value
+			//   "foo": "bar"
+			opKey := string(key)
+			op.operands = append(op.operands, OperationNode{opKey, GetOperatorFactory().Generate("eq", value)})
+		}
+		return nil
+	})
+	return op
+}
+
+func (andOperator *AndOperator) Eval(payload []byte) bool {
+	log.Debug("and "+string(payload))
+	res := true
+	nodesLength := len(andOperator.operands)
+	for i := 0; i < nodesLength ; i++ {
+
+		if len(andOperator.operands[i].key) == 0 {
+			// is an operator
+			res = res && andOperator.operands[i].filter.Eval(payload)
+		} else {
+			// is an normal key
+			val, _, _, _ := jsonparser.Get(payload, andOperator.operands[i].key)
+			res = res && andOperator.operands[i].filter.Eval(val)
+		}
+
+		if res == false {
+			break
+		}
+	}
+	return res
+}
+
+type OrOperator struct {
+	operands []Filter
+}
+
+func orOperatorConstruct(argument []byte) *OrOperator {
+	op := new(OrOperator)
+	_, _ = jsonparser.ArrayEach(argument, func(value []byte, dataType jsonparser.ValueType, offset int, err error) {
+		op.operands = append(op.operands, GetOperatorFactory().Generate("and", value))
+	})
+	return op
+}
+
+func (orOperator OrOperator) Eval(payload []byte) bool {
+	log.Debug("or "+string(payload))
+	res:= false
+	nodesLength := len(orOperator.operands)
+	for i := 0; i < nodesLength ; i++ {
+		res = res || orOperator.operands[i].Eval(payload)
+
+		if res == true {
+			break
+		}
+	}
+	return res
+}
+
+type EqualOperator struct {
+	value []byte
+}
+
+func equalOperatorConstruct(argument []byte) *EqualOperator {
+	op := new(EqualOperator)
+	op.value = argument
+	return op
+}
+
+func (equalOperator EqualOperator) Eval(payload []byte) bool {
+	log.Debug("eq "+string(payload))
+	return bytes.Equal(payload, equalOperator.value)
+}
+
+type NotEqualOperator struct {
+	value []byte
+}
+
+func notEqualOperatorConstruct(argument []byte) *NotEqualOperator {
+	op := new(NotEqualOperator)
+	op.value = argument
+	return op
+}
+
+func (notEqualOperator NotEqualOperator) Eval(payload []byte) bool {
+	log.Debug("neq "+string(payload))
+	return !bytes.Equal(payload, notEqualOperator.value)
+}
+
+
+type InOperator struct {
+	operands [][]byte
+}
+
+func inOperatorConstruct(argument []byte) *InOperator {
+	op := new(InOperator)
+	_, _ = jsonparser.ArrayEach(argument, func(value []byte, dataType jsonparser.ValueType, offset int, err error) {
+		op.operands = append(op.operands, value)
+	})
+	return op
+}
+
+func (inOperator InOperator) Eval(payload []byte) bool {
+	log.Debug("in "+string(payload))
+	res := false
+	for _, v := range inOperator.operands {
+		res = res || bytes.Equal(payload, v)
+		if res == true {
+			break
+		}
+	}
+	return res
+}
+
+type ContainsOperator struct {
+	operand []byte
+}
+
+func containsOperatorConstruct(argument []byte) *ContainsOperator {
+	op := new(ContainsOperator)
+	op.operand = argument
+	return op
+}
+
+func (containsOperator ContainsOperator) Eval(payload []byte) bool {
+	log.Debug("contains "+string(payload))
+	return bytes.Contains(payload, containsOperator.operand)
+}
+
+type RegexOperator struct {
+	regex string
+}
+
+func regexOperatorConstruct(argument []byte) *RegexOperator {
+	op := new(RegexOperator)
+	op.regex = string(argument)
+	return op
+}
+
+func (containsOperator RegexOperator) Eval(payload []byte) bool {
+	log.Debug("regex "+string(payload))
+	matched, _ := regexp.Match(containsOperator.regex, payload)
+	return matched
+}
+// 单例工厂
+type operatorFactory struct{
+}
+
+var instance *operatorFactory = &operatorFactory{}
+
+func GetOperatorFactory() *operatorFactory {
+	return instance
+}
+
+func (o operatorFactory) Generate(opName string, argument []byte) Filter {
+	switch opName {
+	case "not":
+		return notOperatorConstruct(argument)
+	case "and":
+		return andOperatorConstruct(argument)
+	case "or":
+		return orOperatorConstruct(argument)
+	case "neq":
+		return notEqualOperatorConstruct(argument)
+	case "eq":
+		return equalOperatorConstruct(argument)
+	case "in":
+		return inOperatorConstruct(argument)
+	case "contains":
+		return containsOperatorConstruct(argument)
+	case "regex":
+		return regexOperatorConstruct(argument)
+	default:
+		log.Warnf("the operator '%s' is not supported", opName)
+		return nil
+	}
+}
+
+var filter = new(Filter)
+var once sync.Once   // 过滤器单例模式
+
+func GetFilter() *Filter {
+	once.Do(func() {
+		f, err := ioutil.ReadFile("filter.json")
+		if err != nil {
+			filter = nil
+		} else {
+			*filter = GetOperatorFactory().Generate("and", f)
+		}
+	})
+	return filter
+}

go.mod

@@ -4,6 +4,7 @@ go 1.14
 
 require (
 	github.com/Mrs4s/MiraiGo v0.0.0-20200821182324-7654a7a2a106
+	github.com/buger/jsonparser v1.0.0
 	github.com/fastly/go-utils v0.0.0-20180712184237-d95a45783239 // indirect
 	github.com/gin-gonic/gin v1.6.3
 	github.com/gorilla/websocket v1.4.2

go.sum

@@ -6,6 +6,8 @@ github.com/Mrs4s/MiraiGo v0.0.0-20200821164244-fe8e98b9d8c5 h1:LVzj3ahW0LYJQMDcD
 github.com/Mrs4s/MiraiGo v0.0.0-20200821164244-fe8e98b9d8c5/go.mod h1:0je03wji/tSw4bUH4QCF2Z4/EjyNWjSJTyy5tliX6EM=
 github.com/Mrs4s/MiraiGo v0.0.0-20200821182324-7654a7a2a106 h1:z2oaXbvOmu7/O666OkUeH5SGUjyQ3wUSNjtTOagY8Sk=
 github.com/Mrs4s/MiraiGo v0.0.0-20200821182324-7654a7a2a106/go.mod h1:0je03wji/tSw4bUH4QCF2Z4/EjyNWjSJTyy5tliX6EM=
+github.com/buger/jsonparser v1.0.0 h1:etJTGF5ESxjI0Ic2UaLQs2LQQpa8G9ykQScukbh4L8A=
+github.com/buger/jsonparser v1.0.0/go.mod h1:tgcrVJ81GPSF0mz+0nu1Xaz0fazGPrmmJfJtxjbHhUQ=
 github.com/bwmarrin/snowflake v0.3.0 h1:xm67bEhkKh6ij1790JB83OujPR5CzNe8QuQqAgISZN0=
 github.com/bwmarrin/snowflake v0.3.0/go.mod h1:NdZxfVWX+oR6y2K0o6qAYv6gIOP9rjG0/E9WsDpxqwE=
 github.com/census-instrumentation/opencensus-proto v0.2.1/go.mod h1:f6KPmirojxKA12rnyqOA5BBL4O983OfeGPqjHWSTneU=

server/websocket.go

@@ -172,6 +172,12 @@ func (c *websocketClient) listenApi(conn *websocketConn, u bool) {
 }
 
 func (c *websocketClient) onBotPushEvent(m coolq.MSG) {
+	payload := []byte(m.ToJson())
+	filter := global.GetFilter()
+	if filter != nil && (*filter).Eval(payload) == false {
+		log.Debug("Event filtered!")
+		return
+	}
 	if c.eventConn != nil {
 		log.Debugf("向WS服务器 %v 推送Event: %v", c.eventConn.RemoteAddr().String(), m.ToJson())
 		c.eventConn.Lock()