add communicator api

Godeps/Godeps.json

@@ -101,6 +101,10 @@
 			"Comment": "1.0-2-ga096ffc",
 			"Rev": "a096ffc9ada929bb7d920224cad058207d95054b"
 		},
+		{
+			"ImportPath": "github.com/zr-hebo/validator",
+			"Rev": "f57849af19b4b7782c8151eda271eac1b701943b"
+		},
 		{
 			"ImportPath": "golang.org/x/crypto/ssh/terminal",
 			"Rev": "eb71ad9bd329b5ac0fd0148dd99bd62e8be8e035"

capture/config.go

@@ -1,16 +1,17 @@
 package capture
 
 import (
-	sd "github.com/zr-hebo/sniffer-agent/session-dealer"
 	log "github.com/sirupsen/logrus"
-	"sync"
+	sd "github.com/zr-hebo/sniffer-agent/session-dealer"
+	"math/rand"
+	"time"
 )
 
 var (
 	localIPAddr *string
 
 	sessionPool = make(map[string]sd.ConnSession)
-	sessionPoolLock sync.Mutex
+	// sessionPoolLock sync.Mutex
 )
 
 func init() {
@@ -21,4 +22,6 @@ func init() {
 
 	localIPAddr = &ipAddr
 	log.Infof("parsed local ip address:%s", *localIPAddr)
+
+	rand.Seed(time.Now().UnixNano())
 }

capture/network.go

@@ -6,7 +6,9 @@ import (
 	"github.com/google/gopacket"
 	"github.com/google/gopacket/layers"
 	"github.com/google/gopacket/pcap"
+	"github.com/zr-hebo/sniffer-agent/communicator"
 	"golang.org/x/net/bpf"
+	"math/rand"
 	"time"
 
 	"github.com/google/gopacket/pcapgo"
@@ -114,6 +116,20 @@ func (nc *networkCard) listenNormal() {
 				continue
 			}
 
+			// throw packets according to a certain probability
+			throwPacketRate := communicator.GetConfig(communicator.THROW_PACKET_RATE).(float64)
+			if throwPacketRate >= 1.0 {
+				time.Sleep(time.Second*3)
+				continue
+
+			} else if 0 < throwPacketRate && throwPacketRate < 1.0 {
+				// fall into throw range
+				rn := rand.Float64()
+				if rn <= throwPacketRate {
+					continue
+				}
+			}
+
 			packet := gopacket.NewPacket(data, layers.LayerTypeEthernet, gopacket.NoCopy)
 			m := packet.Metadata()
 			m.CaptureInfo = ci

communicator/config.go

@@ -2,13 +2,13 @@ package communicator
 
 import (
 	"flag"
-	"net/http"
-	"strconv"
-	"time"
-
 	"github.com/gorilla/mux"
-	hu "github.com/zr-hebo/util-http"
 	_ "net/http/pprof"
+	"sync"
+)
+
+const (
+	THROW_PACKET_RATE = "throw_packet_rate"
 )
 
 var (
@@ -16,34 +16,15 @@ var (
 	router = mux.NewRouter()
 )
 
+var (
+	configMapLock sync.RWMutex
+	configMap map[string]configItem
+)
+
 func init()  {
 	flag.IntVar(&communicatePort, "communicate_port", 8088, "http server port. Default is 8088")
 
-	router.Path("/get_status").Methods("GET").HandlerFunc(getStatus)
+	configMap = make(map[string]configItem)
-	router.Path("/set_config").Methods("POST").HandlerFunc(setConfig)
+	tprc := newThrowPacketRateConfig()
+	configMap[tprc.name] = tprc
 }
-
-func Server()  {
-	server := &http.Server{
-		Addr:        "0.0.0.0:" + strconv.Itoa(communicatePort),
-		IdleTimeout: time.Second * 5,
-	}
-
-	http.Handle("/", router)
-	if err := server.ListenAndServe(); err != nil {
-		panic(err)
-	}
-}
-
-func getStatus(resp http.ResponseWriter, req *http.Request) {
-	mp := hu.NewMouthpiece(resp)
-	defer mp.Convey()
-	mp.Data = "OK"
-}
-
-func setConfig(resp http.ResponseWriter, req *http.Request) {
-	mp := hu.NewMouthpiece(resp)
-	defer mp.Convey()
-	mp.Data = "OK"
-}
-

communicator/controller.go

@@ -0,0 +1,83 @@
+package communicator
+
+import (
+	"fmt"
+	"net/http"
+	"strconv"
+	"time"
+
+	hu "github.com/zr-hebo/util-http"
+	"github.com/zr-hebo/validator"
+)
+
+func Server() {
+	server := &http.Server{
+		Addr:        "0.0.0.0:" + strconv.Itoa(communicatePort),
+		IdleTimeout: time.Second * 5,
+	}
+
+	http.Handle("/", router)
+	if err := server.ListenAndServe(); err != nil {
+		panic(err)
+	}
+}
+
+func outletCheckAlive(resp http.ResponseWriter, req *http.Request) {
+	mp := hu.NewMouthpiece(resp)
+	defer func() {
+		_ = mp.Convey()
+	}()
+
+	mp.Data = "OK"
+}
+
+func outletGetConfig(resp http.ResponseWriter, req *http.Request) {
+	mp := hu.NewMouthpiece(resp)
+	defer func() {
+		_ = mp.Convey()
+	}()
+
+	ep := &struct {
+		ConfigName string  `validate:"nonzero" json:"config_name"`
+	}{}
+	up := hu.NewUnpacker(req, ep, nil)
+	if err := up.Unpack(); err != nil {
+		mp.Err = err
+		return
+	}
+	if err := validator.Validate(*ep); err != nil {
+		mp.Err = err
+		return
+	}
+
+	_, ok := configMap[ep.ConfigName]
+	if !ok {
+		mp.Err = fmt.Errorf("no config %s found", ep.ConfigName)
+		return
+	}
+
+	mp.Data = GetConfig(ep.ConfigName)
+}
+
+func outletSetConfig(resp http.ResponseWriter, req *http.Request) {
+	mp := hu.NewMouthpiece(resp)
+	defer func() {
+		_ = mp.Convey()
+	}()
+
+	ep := &struct {
+		ConfigName string  `validate:"nonzero" json:"config_name"`
+		Value interface{}  `json:"value"`
+	}{}
+	up := hu.NewUnpacker(req, ep, nil)
+	if err := up.Unpack(); err != nil {
+		mp.Err = err
+		return
+	}
+	if err := validator.Validate(*ep); err != nil {
+		mp.Err = err
+		return
+	}
+
+	mp.Err = SetConfig(ep.ConfigName, ep.Value)
+}

communicator/major_function.go

@@ -0,0 +1,27 @@
+package communicator
+
+import "fmt"
+
+// SetConfig set config by config key(name) and value
+func SetConfig(key string, val interface{}) (err error) {
+	configMapLock.Lock()
+	defer configMapLock.Unlock()
+
+	config, ok := configMap[key]
+	if !ok {
+		err = fmt.Errorf("no config %s exist", key)
+		return
+	}
+
+	err = config.setVal(val)
+	return
+}
+
+// GetConfig get config value by config key(name)
+func GetConfig(key string) (val interface{}) {
+	configMapLock.RLock()
+	defer configMapLock.RUnlock()
+
+	config := configMap[key]
+	return config.getVal()
+}

communicator/model.go

@@ -0,0 +1,36 @@
+package communicator
+
+import "fmt"
+
+type configItem interface {
+	setVal (interface{}) error
+	getVal () interface{}
+}
+
+type throwPacketRateConfig struct {
+	name string
+	value float64
+}
+
+func newThrowPacketRateConfig() (tpr *throwPacketRateConfig) {
+	tpr = &throwPacketRateConfig{
+		name: THROW_PACKET_RATE,
+		value: 0.0,
+	}
+	return
+}
+
+func (tc *throwPacketRateConfig) setVal (val interface{}) (err error){
+	realVal, ok := val.(float64)
+	if !ok {
+		err = fmt.Errorf("cannot reansform val: %v to float64", val)
+		return
+	}
+
+	tc.value = realVal
+	return
+}
+
+func (tc *throwPacketRateConfig) getVal () (val interface{}){
+	return tc.value
+}

communicator/url.go

@@ -0,0 +1,7 @@
+package communicator
+
+func init()  {
+	router.Path("/check_alive").Methods("GET").HandlerFunc(outletCheckAlive)
+	router.Path("/get_config").Methods("GET").HandlerFunc(outletGetConfig)
+	router.Path("/set_config").Methods("POST").HandlerFunc(outletSetConfig)
+}

scripts/generate_mysql_select.sh

@@ -14,11 +14,11 @@ function execute_real(){
     sleep 1
     mysql -h$mysql_host -P$mysql_port -u$user_name -p$passwd sniffer -e ""
     sleep 1
-    insert_cmd="insert into unibase.haha(id, name) values(10, 'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa')"
+    insert_cmd="insert into unibase.haha(id, name) values(10, 'aaaa')"
-    insert_cmd="$insert_cmd,(10, 'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa')"
+    insert_cmd="$insert_cmd,(10, 'aaaa')"
-    insert_cmd="$insert_cmd,(10, 'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa')"
+    insert_cmd="$insert_cmd,(10, 'aaaa')"
-    insert_cmd="$insert_cmd,(10, 'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa')"
+    insert_cmd="$insert_cmd,(10, 'aaaa')"
-    insert_cmd="$insert_cmd,(10, 'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa')"
+    insert_cmd="$insert_cmd,(10, 'aaaa')"
     mysql -h$mysql_host -P$mysql_port -u$user_name -p$passwd sniffer -e "$insert_cmd"
     sleep 1
     mysql -h$mysql_host -P$mysql_port -u$user_name -p$passwd sniffer -e "use unibase; select * from haha; drop table haha"

session-dealer/mysql/const.go

@@ -41,7 +41,7 @@ const (
 )
 
 const (
-	ComAuth = 141
+	maxSQLLen = 5*1024*1024
 )
 
 // Client information.

session-dealer/mysql/session.go

@@ -24,6 +24,7 @@ type MysqlSession struct {
 	packageOffset            int64
 	expectReceiveSize        int
 	coverRanges              []*jigsaw
+	coverRange               *jigsaw
 	expectSendSize           int
 	prepareInfo              *prepareInfo
 	cachedPrepareStmt        map[int][]byte
@@ -137,6 +138,7 @@ func mergeRanges(currRange *jigsaw, pkgRanges []*jigsaw) (mergedRange *jigsaw, n
 		return currRange, newPkgRanges
 
 	} else if len(pkgRanges) == 1 {
+		//
 		nextRange = pkgRanges[0]
 
 	} else {
@@ -253,6 +255,7 @@ func (ms *MysqlSession) GenerateQueryPiece() (qp model.QueryPiece) {
 		ms.expectSendSize = 0
 		ms.prepareInfo = nil
 		ms.coverRanges = make([]*jigsaw, 0, 4)
+		ms.coverRange = nil
 		ms.lastSeq = -1
 		ms.ignoreAckID = -1
 		ms.sendSize = 0
@@ -267,6 +270,11 @@ func (ms *MysqlSession) GenerateQueryPiece() (qp model.QueryPiece) {
 		return
 	}
 
+	if len(ms.cachedStmtBytes) > maxSQLLen {
+		log.Warn("sql in cache is too long, ignore it")
+		return
+	}
+
 	var mqp *model.PooledMysqlQueryPiece
 	var querySQLInBytes []byte
 	if ms.cachedStmtBytes[0] > 32 {
@@ -327,7 +335,6 @@ func (ms *MysqlSession) GenerateQueryPiece() (qp model.QueryPiece) {
 		}
 	}
 
-
 	if strictMode && mqp != nil && mqp.VisitUser == nil {
 		user, db, err := querySessionInfo(ms.serverPort, mqp.SessionID)
 		if err != nil {

vendor/github.com/zr-hebo/validator/.gitignore

@@ -0,0 +1,23 @@
+# Compiled Object files, Static and Dynamic libs (Shared Objects)
+*.o
+*.a
+*.so
+
+# Folders
+_obj
+_test
+
+# Architecture specific extensions/prefixes
+*.[568vq]
+[568vq].out
+
+*.cgo1.go
+*.cgo2.c
+_cgo_defun.c
+_cgo_gotypes.go
+_cgo_export.*
+
+_testmain.go
+
+*.exe
+*.test

vendor/github.com/zr-hebo/validator/.travis.yml

@@ -0,0 +1,10 @@
+language: go
+go:
+  - 1.5
+  - 1.6
+  - 1.7
+go_import_path: gopkg.in/validator.v2
+script:
+  - go test -race -v -bench=.
+notifications:
+  email: false

vendor/github.com/zr-hebo/validator/LICENSE

@@ -0,0 +1,201 @@
+Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
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+
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+      and distribution as defined by Sections 1 through 9 of this document.
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+
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+      other entities that control, are controlled by, or are under common
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vendor/github.com/zr-hebo/validator/README.md

@@ -0,0 +1,167 @@
+Package validator
+================
+
+Package validator implements variable validations
+
+Installation
+============
+
+Just use go get.
+
+	go get gopkg.in/validator.v2
+
+And then just import the package into your own code.
+
+	import (
+		"gopkg.in/validator.v2"
+	)
+
+Usage
+=====
+
+Please see http://godoc.org/gopkg.in/validator.v2 for detailed usage docs.
+A simple example would be.
+
+	type NewUserRequest struct {
+		Username string `validate:"min=3,max=40,regexp=^[a-zA-Z]*$"`
+		Name string     `validate:"nonzero"`
+		Age int         `validate:"min=21"`
+		Password string `validate:"min=8"`
+	}
+
+	nur := NewUserRequest{Username: "something", Age: 20}
+	if errs := validator.Validate(nur); errs != nil {
+		// values not valid, deal with errors here
+	}
+
+
+Builtin validators
+
+Here is the list of validators buildin in the package.
+
+	len
+		For numeric numbers, max will simply make sure that the
+		value is equal to the parameter given. For strings, it
+		checks that the string length is exactly that number of
+		characters. For slices,	arrays, and maps, validates the
+		number of items. (Usage: len=10)
+	
+	max
+		For numeric numbers, max will simply make sure that the
+		value is lesser or equal to the parameter given. For strings,
+		it checks that the string length is at most that number of
+		characters. For slices,	arrays, and maps, validates the
+		number of items. (Usage: max=10)
+	
+	min
+		For numeric numbers, min will simply make sure that the value
+		is greater or equal to the parameter given. For strings, it
+		checks that the string length is at least that number of
+		characters. For slices, arrays, and maps, validates the
+		number of items. (Usage: min=10)
+	
+	nonzero
+		This validates that the value is not zero. The appropriate
+		zero value is given by the Go spec (e.g. for int it's 0, for
+		string it's "", for pointers is nil, etc.) For structs, it
+		will not check to see if the struct itself has all zero
+		values, instead use a pointer or put nonzero on the struct's
+		keys that you care about. (Usage: nonzero)
+	
+	regexp
+		Only valid for string types, it will validator that the
+		value matches the regular expression provided as parameter.
+		(Usage: regexp=^a.*b$)
+
+Custom validators
+
+It is possible to define custom validators by using SetValidationFunc.
+First, one needs to create a validation function.
+
+	// Very simple validator
+	func notZZ(v interface{}, param string) error {
+		st := reflect.ValueOf(v)
+		if st.Kind() != reflect.String {
+			return errors.New("notZZ only validates strings")
+		}
+		if st.String() == "ZZ" {
+			return errors.New("value cannot be ZZ")
+		}
+		return nil
+	}
+
+Then one needs to add it to the list of validators and give it a "tag"
+name.
+
+	validator.SetValidationFunc("notzz", notZZ)
+
+Then it is possible to use the notzz validation tag. This will print
+"Field A error: value cannot be ZZ"
+
+	type T struct {
+		A string  `validate:"nonzero,notzz"`
+	}
+	t := T{"ZZ"}
+	if errs := validator.Validate(t); errs != nil {
+		fmt.Printf("Field A error: %s\n", errs["A"][0])
+	}
+
+You can also have multiple sets of validator rules with SetTag().
+
+	type T struct {
+		A int `foo:"nonzero" bar:"min=10"`
+	}
+	t := T{5}
+	SetTag("foo")
+	validator.Validate(t) // valid as it's nonzero
+	SetTag("bar")
+	validator.Validate(t) // invalid as it's less than 10
+
+SetTag is probably better used with multiple validators.
+
+	fooValidator := validator.NewValidator()
+	fooValidator.SetTag("foo")
+	barValidator := validator.NewValidator()
+	barValidator.SetTag("bar")
+	fooValidator.Validate(t)
+	barValidator.Validate(t)
+
+This keeps the default validator's tag clean. Again, please refer to
+godocs for a lot of more examples and different uses.
+
+Pull requests policy
+====================
+
+tl;dr. Contributions are welcome.
+
+The repository is organized in version branches. Pull requests to, say, the
+`v2` branch that break API compatibility will not be accepted. It is okay to
+break the API in master, *not in the branches*.
+
+As for validation functions, the preference is to keep the main code simple
+and add most new functions to the validator-contrib repository.
+
+https://github.com/go-validator/validator-contrib
+
+For improvements and/or fixes to the builtin validation functions, please
+make sure the behaviour will not break existing functionality in the branches.
+If you see a case where the functionality of the builtin will change
+significantly, please send a pull request against `master`. We can discuss then
+whether the changes should be incorporated in the version branches as well.
+
+License
+=======
+
+Copyright 2014 Roberto Teixeira <robteix@robteix.com>
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.

vendor/github.com/zr-hebo/validator/builtins.go

@@ -0,0 +1,246 @@
+// Package validator implements value validations
+//
+// Copyright 2014 Roberto Teixeira <robteix@robteix.com>
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package validator
+
+import (
+	"reflect"
+	"regexp"
+	"strconv"
+)
+
+// nonzero tests whether a variable value non-zero
+// as defined by the golang spec.
+func nonzero(v interface{}, param string) error {
+	st := reflect.ValueOf(v)
+	valid := true
+	switch st.Kind() {
+	case reflect.String:
+		valid = len(st.String()) != 0
+	case reflect.Ptr, reflect.Interface:
+		valid = !st.IsNil()
+	case reflect.Slice, reflect.Map, reflect.Array:
+		valid = st.Len() != 0
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		valid = st.Int() != 0
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		valid = st.Uint() != 0
+	case reflect.Float32, reflect.Float64:
+		valid = st.Float() != 0
+	case reflect.Bool:
+		valid = st.Bool()
+	case reflect.Invalid:
+		valid = false // always invalid
+	case reflect.Struct:
+		valid = true // always valid since only nil pointers are empty
+	default:
+		return ErrUnsupported
+	}
+
+	if !valid {
+		return ErrZeroValue
+	}
+	return nil
+}
+
+// length tests whether a variable's length is equal to a given
+// value. For strings it tests the number of characters whereas
+// for maps and slices it tests the number of items.
+func length(v interface{}, param string) error {
+	st := reflect.ValueOf(v)
+	valid := true
+	switch st.Kind() {
+	case reflect.String:
+		p, err := asInt(param)
+		if err != nil {
+			return ErrBadParameter
+		}
+		valid = int64(len(st.String())) == p
+	case reflect.Slice, reflect.Map, reflect.Array:
+		p, err := asInt(param)
+		if err != nil {
+			return ErrBadParameter
+		}
+		valid = int64(st.Len()) == p
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		p, err := asInt(param)
+		if err != nil {
+			return ErrBadParameter
+		}
+		valid = st.Int() == p
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		p, err := asUint(param)
+		if err != nil {
+			return ErrBadParameter
+		}
+		valid = st.Uint() == p
+	case reflect.Float32, reflect.Float64:
+		p, err := asFloat(param)
+		if err != nil {
+			return ErrBadParameter
+		}
+		valid = st.Float() == p
+	default:
+		return ErrUnsupported
+	}
+	if !valid {
+		return ErrLen
+	}
+	return nil
+}
+
+// min tests whether a variable value is larger or equal to a given
+// number. For number types, it's a simple lesser-than test; for
+// strings it tests the number of characters whereas for maps
+// and slices it tests the number of items.
+func min(v interface{}, param string) error {
+	st := reflect.ValueOf(v)
+	invalid := false
+	switch st.Kind() {
+	case reflect.String:
+		p, err := asInt(param)
+		if err != nil {
+			return ErrBadParameter
+		}
+		invalid = int64(len(st.String())) < p
+	case reflect.Slice, reflect.Map, reflect.Array:
+		p, err := asInt(param)
+		if err != nil {
+			return ErrBadParameter
+		}
+		invalid = int64(st.Len()) < p
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		p, err := asInt(param)
+		if err != nil {
+			return ErrBadParameter
+		}
+		invalid = st.Int() < p
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		p, err := asUint(param)
+		if err != nil {
+			return ErrBadParameter
+		}
+		invalid = st.Uint() < p
+	case reflect.Float32, reflect.Float64:
+		p, err := asFloat(param)
+		if err != nil {
+			return ErrBadParameter
+		}
+		invalid = st.Float() < p
+	default:
+		return ErrUnsupported
+	}
+	if invalid {
+		return ErrMin
+	}
+	return nil
+}
+
+// max tests whether a variable value is lesser than a given
+// value. For numbers, it's a simple lesser-than test; for
+// strings it tests the number of characters whereas for maps
+// and slices it tests the number of items.
+func max(v interface{}, param string) error {
+	st := reflect.ValueOf(v)
+	var invalid bool
+	switch st.Kind() {
+	case reflect.String:
+		p, err := asInt(param)
+		if err != nil {
+			return ErrBadParameter
+		}
+		invalid = int64(len(st.String())) > p
+	case reflect.Slice, reflect.Map, reflect.Array:
+		p, err := asInt(param)
+		if err != nil {
+			return ErrBadParameter
+		}
+		invalid = int64(st.Len()) > p
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		p, err := asInt(param)
+		if err != nil {
+			return ErrBadParameter
+		}
+		invalid = st.Int() > p
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		p, err := asUint(param)
+		if err != nil {
+			return ErrBadParameter
+		}
+		invalid = st.Uint() > p
+	case reflect.Float32, reflect.Float64:
+		p, err := asFloat(param)
+		if err != nil {
+			return ErrBadParameter
+		}
+		invalid = st.Float() > p
+	default:
+		return ErrUnsupported
+	}
+	if invalid {
+		return ErrMax
+	}
+	return nil
+}
+
+// regex is the builtin validation function that checks
+// whether the string variable matches a regular expression
+func regex(v interface{}, param string) error {
+	s, ok := v.(string)
+	if !ok {
+		return ErrUnsupported
+	}
+
+	re, err := regexp.Compile(param)
+	if err != nil {
+		return ErrBadParameter
+	}
+
+	if !re.MatchString(s) {
+		return ErrRegexp
+	}
+	return nil
+}
+
+// asInt retuns the parameter as a int64
+// or panics if it can't convert
+func asInt(param string) (int64, error) {
+	i, err := strconv.ParseInt(param, 0, 64)
+	if err != nil {
+		return 0, ErrBadParameter
+	}
+	return i, nil
+}
+
+// asUint retuns the parameter as a uint64
+// or panics if it can't convert
+func asUint(param string) (uint64, error) {
+	i, err := strconv.ParseUint(param, 0, 64)
+	if err != nil {
+		return 0, ErrBadParameter
+	}
+	return i, nil
+}
+
+// asFloat retuns the parameter as a float64
+// or panics if it can't convert
+func asFloat(param string) (float64, error) {
+	i, err := strconv.ParseFloat(param, 64)
+	if err != nil {
+		return 0.0, ErrBadParameter
+	}
+	return i, nil
+}

vendor/github.com/zr-hebo/validator/doc.go

@@ -0,0 +1,265 @@
+// Package validator implements value validations
+//
+// Copyright 2014 Roberto Teixeira <robteix@robteix.com>
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/*
+Package validator implements value validations based on struct tags.
+
+In code it is often necessary to validate that a given value is valid before
+using it for something. A typical example might be something like this.
+
+	if age < 18 {
+		return error.New("age cannot be under 18")
+	}
+
+This is a simple enough example, but it can get significantly more complex,
+especially when dealing with structs.
+
+	l := len(strings.Trim(s.Username))
+	if l < 3 || l > 40  || !regexp.MatchString("^[a-zA-Z]$", s.Username) ||	s.Age < 18 || s.Password {
+		return errors.New("Invalid request")
+	}
+
+You get the idea. Package validator allows one to define valid values as
+struct tags when defining a new struct type.
+
+	type NewUserRequest struct {
+		Username string `validate:"min=3,max=40,regexp=^[a-zA-Z]*$"`
+		Name string     `validate:"nonzero"`
+		Age int         `validate:"min=18"`
+		Password string `validate:"min=8"`
+	}
+
+Then validating a variable of type NewUserRequest becomes trivial.
+
+	nur := NewUserRequest{Username: "something", ...}
+	if errs := validator.Validate(nur); errs != nil {
+		// do something
+	}
+
+Builtin validator functions
+
+Here is the list of validator functions builtin in the package.
+
+	len
+		For numeric numbers, len will simply make sure that the value is
+		equal to the parameter given. For strings, it checks that
+		the string length is exactly that number of characters. For slices,
+		arrays, and maps, validates the number of items. (Usage: len=10)
+
+	max
+		For numeric numbers, max will simply make sure that the value is
+		lesser or equal to the parameter given. For strings, it checks that
+		the string length is at most that number of characters. For slices,
+		arrays, and maps, validates the number of items. (Usage: max=10)
+
+	min
+		For numeric numbers, min will simply make sure that the value is
+		greater or equal to the parameter given. For strings, it checks that
+		the string length is at least that number of characters. For slices,
+		arrays, and maps, validates the number of items. (Usage: min=10)
+
+	nonzero
+		This validates that the value is not zero. The appropriate zero value
+		is given by the Go spec (e.g. for int it's 0, for string it's "", for
+		pointers is nil, etc.) Usage: nonzero
+
+	regexp
+		Only valid for string types, it will validate that the value matches
+		the regular expression provided as parameter. (Usage: regexp=^a.*b$)
+
+
+Note that there are no tests to prevent conflicting validator parameters. For
+instance, these fields will never be valid.
+
+	...
+	A int     `validate:"max=0,min=1"`
+	B string  `validate:"len=10,regexp=^$"
+	...
+
+Custom validation functions
+
+It is possible to define custom validation functions by using SetValidationFunc.
+First, one needs to create a validation function.
+
+	// Very simple validation func
+	func notZZ(v interface{}, param string) error {
+		st := reflect.ValueOf(v)
+		if st.Kind() != reflect.String {
+			return validate.ErrUnsupported
+		}
+		if st.String() == "ZZ" {
+			return errors.New("value cannot be ZZ")
+		}
+		return nil
+	}
+
+Then one needs to add it to the list of validation funcs and give it a "tag" name.
+
+	validate.SetValidationFunc("notzz", notZZ)
+
+Then it is possible to use the notzz validation tag. This will print
+"Field A error: value cannot be ZZ"
+
+	type T struct {
+		A string  `validate:"nonzero,notzz"`
+	}
+	t := T{"ZZ"}
+	if errs := validator.Validate(t); errs != nil {
+		fmt.Printf("Field A error: %s\n", errs["A"][0])
+	}
+
+To use parameters, it is very similar.
+
+	// Very simple validator with parameter
+	func notSomething(v interface{}, param string) error {
+		st := reflect.ValueOf(v)
+		if st.Kind() != reflect.String {
+			return validate.ErrUnsupported
+		}
+		if st.String() == param {
+			return errors.New("value cannot be " + param)
+		}
+		return nil
+	}
+
+And then the code below should print "Field A error: value cannot be ABC".
+
+	validator.SetValidationFunc("notsomething", notSomething)
+	type T struct {
+		A string  `validate:"notsomething=ABC"`
+	}
+	t := T{"ABC"}
+	if errs := validator.Validate(t); errs != nil {
+		fmt.Printf("Field A error: %s\n", errs["A"][0])
+	}
+
+As well, it is possible to overwrite builtin validation functions.
+
+	validate.SetValidationFunc("min", myMinFunc)
+
+And you can delete a validation function by setting it to nil.
+
+	validate.SetValidationFunc("notzz", nil)
+	validate.SetValidationFunc("nonzero", nil)
+
+Using a non-existing validation func in a field tag will always return
+false and with error validate.ErrUnknownTag.
+
+Finally, package validator also provides a helper function that can be used
+to validate simple variables/values.
+
+    	// errs: nil
+	errs = validator.Valid(42, "min=10, max=50")
+
+	// errs: [validate.ErrZeroValue]
+	errs = validator.Valid(nil, "nonzero")
+
+	// errs: [validate.ErrMin,validate.ErrMax]
+	errs = validator.Valid("hi", "nonzero,min=3,max=2")
+
+Custom tag name
+
+In case there is a reason why one would not wish to use tag 'validate' (maybe due to
+a conflict with a different package), it is possible to tell the package to use
+a different tag.
+
+	validator.SetTag("valid")
+
+Then.
+
+	Type T struct {
+		A int    `valid:"min=8, max=10"`
+		B string `valid:"nonzero"`
+	}
+
+SetTag is permanent. The new tag name will be used until it is again changed
+with a new call to SetTag. A way to temporarily use a different tag exists.
+
+	validator.WithTag("foo").Validate(t)
+	validator.WithTag("bar").Validate(t)
+	// But this will go back to using 'validate'
+	validator.Validate(t)
+
+Multiple validators
+
+You may often need to have a different set of validation
+rules for different situations. In all the examples above,
+we only used the default validator but you could create a
+new one and set specific rules for it.
+
+For instance, you might use the same struct to decode incoming JSON for a REST API
+but your needs will change when you're using it to, say, create a new instance
+in storage vs. when you need to change something.
+
+	type User struct {
+		Username string `validate:"nonzero"`
+		Name string     `validate:"nonzero"`
+		Age int         `validate:"nonzero"`
+		Password string `validate:"nonzero"`
+	}
+
+Maybe when creating a new user, you need to make sure all values in the struct are filled,
+but then you use the same struct to handle incoming requests to, say, change the password,
+in which case you only need the Username and the Password and don't care for the others.
+You might use two different validators.
+
+	type User struct {
+		Username string `creating:"nonzero" chgpw:"nonzero"`
+		Name string     `creating:"nonzero"`
+		Age int         `creating:"nonzero"`
+		Password string `creating:"nonzero" chgpw:"nonzero"`
+	}
+
+	var (
+		creationValidator = validator.NewValidator()
+		chgPwValidator = validator.NewValidator()
+	)
+
+	func init() {
+		creationValidator.SetTag("creating")
+		chgPwValidator.SetTag("chgpw")
+	}
+
+	...
+
+	func CreateUserHandler(w http.ResponseWriter, r *http.Request) {
+		var u User
+		json.NewDecoder(r.Body).Decode(&user)
+		if errs := creationValidator.Validate(user); errs != nil {
+			// the request did not include all of the User
+			// struct fields, so send a http.StatusBadRequest
+			// back or something
+		}
+		// create the new user
+	}
+
+	func SetNewUserPasswordHandler(w http.ResponseWriter, r *http.Request) {
+		var u User
+		json.NewDecoder(r.Body).Decode(&user)
+		if errs := chgPwValidator.Validate(user); errs != nil {
+			// the request did not Username and Password,
+			// so send a http.StatusBadRequest
+			// back or something
+		}
+		// save the new password
+	}
+
+It is also possible to do all of that using only the default validator as long
+as SetTag is always called before calling validator.Validate() or you chain the
+with WithTag().
+
+*/
+package validator

vendor/github.com/zr-hebo/validator/validator.go

@@ -0,0 +1,372 @@
+// Package validator implements value validations
+//
+// Copyright 2014 Roberto Teixeira <robteix@robteix.com>
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+package validator
+
+import (
+	"errors"
+	"fmt"
+	"reflect"
+	"regexp"
+	"strings"
+	"unicode"
+)
+
+// TextErr is an error that also implements the TextMarshaller interface for
+// serializing out to various plain text encodings. Packages creating their
+// own custom errors should use TextErr if they're intending to use serializing
+// formats like json, msgpack etc.
+type TextErr struct {
+	Err error
+}
+
+// Error implements the error interface.
+func (t TextErr) Error() string {
+	return t.Err.Error()
+}
+
+// MarshalText implements the TextMarshaller
+func (t TextErr) MarshalText() ([]byte, error) {
+	return []byte(t.Err.Error()), nil
+}
+
+var (
+	// ErrZeroValue is the error returned when variable has zero valud
+	// and nonzero was specified
+	ErrZeroValue = TextErr{errors.New("不能为空！")}
+	// ErrMin is the error returned when variable is less than mininum
+	// value specified
+	ErrMin = TextErr{errors.New("不能小于最小值")}
+	// ErrMax is the error returned when variable is more than
+	// maximum specified
+	ErrMax = TextErr{errors.New("不能大于最大值")}
+	// ErrLen is the error returned when length is not equal to
+	// param specified
+	ErrLen = TextErr{errors.New("无效的长度")}
+	// ErrRegexp is the error returned when the value does not
+	// match the provided regular expression parameter
+	ErrRegexp = TextErr{errors.New("不能匹配对应的正则")}
+	// ErrUnsupported is the error error returned when a validation rule
+	// is used with an unsupported variable type
+	ErrUnsupported = TextErr{errors.New("不支持的验证类型")}
+	// ErrBadParameter is the error returned when an invalid parameter
+	// is provided to a validation rule (e.g. a string where an int was
+	// expected (max=foo,len=bar) or missing a parameter when one is required (len=))
+	ErrBadParameter = TextErr{errors.New("无效的参数")}
+	// ErrUnknownTag is the error returned when an unknown tag is found
+	ErrUnknownTag = TextErr{errors.New("unknown tag")}
+	// ErrInvalid is the error returned when variable is invalid
+	// (normally a nil pointer)
+	ErrInvalid = TextErr{errors.New("invalid value")}
+)
+
+// ErrorMap is a map which contains all errors from validating a struct.
+type ErrorMap map[string]ErrorArray
+
+// ErrorMap implements the Error interface so we can check error against nil.
+// The returned error is if existent the first error which was added to the map.
+func (err ErrorMap) Error() string {
+	for k, errs := range err {
+		if len(errs) > 0 {
+			return fmt.Sprintf("验证 %s 失败: %s", k, errs.Error())
+		}
+	}
+
+	return ""
+}
+
+// ErrorArray is a slice of errors returned by the Validate function.
+type ErrorArray []error
+
+// ErrorArray implements the Error interface and returns the first error as
+// string if existent.
+func (err ErrorArray) Error() string {
+	if len(err) > 0 {
+		return err[0].Error()
+	}
+	return ""
+}
+
+// ValidationFunc is a function that receives the value of a
+// field and a parameter used for the respective validation tag.
+type ValidationFunc func(v interface{}, param string) error
+
+// Validator implements a validator
+type Validator struct {
+	// Tag name being used.
+	tagName string
+	// validationFuncs is a map of ValidationFuncs indexed
+	// by their name.
+	validationFuncs map[string]ValidationFunc
+}
+
+// Helper validator so users can use the
+// functions directly from the package
+var defaultValidator = NewValidator()
+
+// NewValidator creates a new Validator
+func NewValidator() *Validator {
+	return &Validator{
+		tagName: "validate",
+		validationFuncs: map[string]ValidationFunc{
+			"nonzero": nonzero,
+			"len":     length,
+			"min":     min,
+			"max":     max,
+			"regexp":  regex,
+		},
+	}
+}
+
+// SetTag allows you to change the tag name used in structs
+func SetTag(tag string) {
+	defaultValidator.SetTag(tag)
+}
+
+// SetTag allows you to change the tag name used in structs
+func (mv *Validator) SetTag(tag string) {
+	mv.tagName = tag
+}
+
+// WithTag creates a new Validator with the new tag name. It is
+// useful to chain-call with Validate so we don't change the tag
+// name permanently: validator.WithTag("foo").Validate(t)
+func WithTag(tag string) *Validator {
+	return defaultValidator.WithTag(tag)
+}
+
+// WithTag creates a new Validator with the new tag name. It is
+// useful to chain-call with Validate so we don't change the tag
+// name permanently: validator.WithTag("foo").Validate(t)
+func (mv *Validator) WithTag(tag string) *Validator {
+	v := mv.copy()
+	v.SetTag(tag)
+	return v
+}
+
+// Copy a validator
+func (mv *Validator) copy() *Validator {
+	newFuncs := map[string]ValidationFunc{}
+	for k, f := range mv.validationFuncs {
+		newFuncs[k] = f
+	}
+	return &Validator{
+		tagName:         mv.tagName,
+		validationFuncs: newFuncs,
+	}
+}
+
+// SetValidationFunc sets the function to be used for a given
+// validation constraint. Calling this function with nil vf
+// is the same as removing the constraint function from the list.
+func SetValidationFunc(name string, vf ValidationFunc) error {
+	return defaultValidator.SetValidationFunc(name, vf)
+}
+
+// SetValidationFunc sets the function to be used for a given
+// validation constraint. Calling this function with nil vf
+// is the same as removing the constraint function from the list.
+func (mv *Validator) SetValidationFunc(name string, vf ValidationFunc) error {
+	if name == "" {
+		return errors.New("name cannot be empty")
+	}
+	if vf == nil {
+		delete(mv.validationFuncs, name)
+		return nil
+	}
+	mv.validationFuncs[name] = vf
+	return nil
+}
+
+// Validate validates the fields of a struct based
+// on 'validator' tags and returns errors found indexed
+// by the field name.
+func Validate(v interface{}) error {
+	return defaultValidator.Validate(v)
+}
+
+// Validate validates the fields of a struct based
+// on 'validator' tags and returns errors found indexed
+// by the field name.
+func (mv *Validator) Validate(v interface{}) error {
+	sv := reflect.ValueOf(v)
+	st := reflect.TypeOf(v)
+	if sv.Kind() == reflect.Ptr && !sv.IsNil() {
+		return mv.Validate(sv.Elem().Interface())
+	}
+	if sv.Kind() != reflect.Struct && sv.Kind() != reflect.Interface {
+		return ErrUnsupported
+	}
+
+	nfields := sv.NumField()
+	m := make(ErrorMap)
+	for i := 0; i < nfields; i++ {
+		fname := st.Field(i).Name
+		if !unicode.IsUpper(rune(fname[0])) {
+			continue
+		}
+
+		f := sv.Field(i)
+		// deal with pointers
+		for f.Kind() == reflect.Ptr && !f.IsNil() {
+			f = f.Elem()
+		}
+		tag := st.Field(i).Tag.Get(mv.tagName)
+		if tag == "-" {
+			continue
+		}
+		var errs ErrorArray
+
+		if tag != "" {
+			err := mv.Valid(f.Interface(), tag)
+			if errors, ok := err.(ErrorArray); ok {
+				errs = errors
+			} else {
+				if err != nil {
+					errs = ErrorArray{err}
+				}
+			}
+		}
+
+		mv.deepValidateCollection(f, fname, m) // no-op if field is not a struct, interface, array, slice or map
+
+		showFieldName := st.Field(i).Tag.Get("json")
+		if len(showFieldName) < 1 {
+			showFieldName = st.Field(i).Name
+		}
+		if len(errs) > 0 {
+			m[showFieldName] = errs
+		}
+	}
+
+	if len(m) > 0 {
+		return m
+	}
+	return nil
+}
+
+func (mv *Validator) deepValidateCollection(f reflect.Value, fname string, m ErrorMap) {
+	switch f.Kind() {
+	case reflect.Struct, reflect.Interface, reflect.Ptr:
+		e := mv.Validate(f.Interface())
+		if e, ok := e.(ErrorMap); ok && len(e) > 0 {
+			for j, k := range e {
+				m[fname+"."+j] = k
+			}
+		}
+	case reflect.Array, reflect.Slice:
+		for i := 0; i < f.Len(); i++ {
+			mv.deepValidateCollection(f.Index(i), fmt.Sprintf("%s[%d]", fname, i), m)
+		}
+	case reflect.Map:
+		for _, key := range f.MapKeys() {
+			mv.deepValidateCollection(key, fmt.Sprintf("%s[%+v](key)", fname, key.Interface()), m) // validate the map key
+			value := f.MapIndex(key)
+			mv.deepValidateCollection(value, fmt.Sprintf("%s[%+v](value)", fname, key.Interface()), m)
+		}
+	}
+}
+
+// Valid validates a value based on the provided
+// tags and returns errors found or nil.
+func Valid(val interface{}, tags string) error {
+	return defaultValidator.Valid(val, tags)
+}
+
+// Valid validates a value based on the provided
+// tags and returns errors found or nil.
+func (mv *Validator) Valid(val interface{}, tags string) error {
+	if tags == "-" {
+		return nil
+	}
+	v := reflect.ValueOf(val)
+	if v.Kind() == reflect.Ptr && !v.IsNil() {
+		return mv.Valid(v.Elem().Interface(), tags)
+	}
+	var err error
+	switch v.Kind() {
+	case reflect.Invalid:
+		err = mv.validateVar(nil, tags)
+	default:
+		err = mv.validateVar(val, tags)
+	}
+	return err
+}
+
+// validateVar validates one single variable
+func (mv *Validator) validateVar(v interface{}, tag string) error {
+	tags, err := mv.parseTags(tag)
+	if err != nil {
+		// unknown tag found, give up.
+		return err
+	}
+	errs := make(ErrorArray, 0, len(tags))
+	for _, t := range tags {
+		if err := t.Fn(v, t.Param); err != nil {
+			errs = append(errs, err)
+		}
+	}
+	if len(errs) > 0 {
+		return errs
+	}
+	return nil
+}
+
+// tag represents one of the tag items
+type tag struct {
+	Name  string         // name of the tag
+	Fn    ValidationFunc // validation function to call
+	Param string         // parameter to send to the validation function
+}
+
+// separate by no escaped commas
+var sepPattern = regexp.MustCompile(`((?:^|[^\\])(?:\\\\)*),`)
+
+func splitUnescapedComma(str string) []string {
+	ret := []string{}
+	indexes := sepPattern.FindAllStringIndex(str, -1)
+	last := 0
+	for _, is := range indexes {
+		ret = append(ret, str[last:is[1]-1])
+		last = is[1]
+	}
+	ret = append(ret, str[last:])
+	return ret
+}
+
+// parseTags parses all individual tags found within a struct tag.
+func (mv *Validator) parseTags(t string) ([]tag, error) {
+	tl := splitUnescapedComma(t)
+	tags := make([]tag, 0, len(tl))
+	for _, i := range tl {
+		i = strings.Replace(i, `\,`, ",", -1)
+		tg := tag{}
+		v := strings.SplitN(i, "=", 2)
+		tg.Name = strings.Trim(v[0], " ")
+		if tg.Name == "" {
+			return []tag{}, ErrUnknownTag
+		}
+		if len(v) > 1 {
+			tg.Param = strings.Trim(v[1], " ")
+		}
+		var found bool
+		if tg.Fn, found = mv.validationFuncs[tg.Name]; !found {
+			return []tag{}, ErrUnknownTag
+		}
+		tags = append(tags, tg)
+
+	}
+	return tags, nil
+}