mirror of
https://github.com/alibaba/higress.git
synced 2026-06-09 04:37:31 +08:00
feat: Add request and response transformer wasm plugin (#549)
This commit is contained in:
WeixinX
GitHub
965
plugins/wasm-go/extensions/transformer/main.go
Normal file
965
plugins/wasm-go/extensions/transformer/main.go
Normal file
@@ -0,0 +1,965 @@
|
||||
// Copyright (c) 2022 Alibaba Group Holding Ltd.
|
||||
//
|
||||
// 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 main
|
||||
|
||||
import (
|
||||
"regexp"
|
||||
"strings"
|
||||
|
||||
"github.com/alibaba/higress/plugins/wasm-go/pkg/wrapper"
|
||||
|
||||
"github.com/pkg/errors"
|
||||
"github.com/tetratelabs/proxy-wasm-go-sdk/proxywasm"
|
||||
"github.com/tetratelabs/proxy-wasm-go-sdk/proxywasm/types"
|
||||
"github.com/tidwall/gjson"
|
||||
"github.com/tidwall/sjson"
|
||||
)
|
||||
|
||||
func main() {
|
||||
wrapper.SetCtx(
|
||||
"transformer",
|
||||
wrapper.ParseConfigBy(parseConfig),
|
||||
wrapper.ProcessRequestHeadersBy(onHttpRequestHeaders),
|
||||
wrapper.ProcessRequestBodyBy(onHttpRequestBody),
|
||||
wrapper.ProcessResponseHeadersBy(onHttpResponseHeaders),
|
||||
wrapper.ProcessResponseBodyBy(onHttpResponseBody),
|
||||
)
|
||||
}
|
||||
|
||||
// @Name transformer
|
||||
// @Category custom
|
||||
// @Phase UNSPECIFIED_PHASE
|
||||
// @Priority 100
|
||||
// @Title zh-CN 请求/响应转换器
|
||||
// @Title en-US Request/Response Transformer
|
||||
// @Description zh-CN transformer 插件可以对请求/响应头、请求查询参数、请求/响应体参数进行转换，支持的转换操作类型包括删除、重命名、更新、添加、追加、映射、去重。
|
||||
// @Description en-US The transformer plugin can transform request/response headers, request query parameters, and request/response body parameters. Supported transform operations include remove, rename, replace, add, append, map, and dedupe.
|
||||
// @IconUrl https://img.alicdn.com/imgextra/i1/O1CN018iKKih1iVx287RltL_!!6000000004419-2-tps-42-42.png
|
||||
// @Version 1.0.0
|
||||
//
|
||||
// @Contact.name Higress Team
|
||||
// @Contact.url http://higress.io/
|
||||
// @Contact.email admin@higress.io
|
||||
//
|
||||
// @Example
|
||||
// type: request
|
||||
// rules:
|
||||
// - operate: remove
|
||||
// headers:
|
||||
// - key: X-remove
|
||||
// querys:
|
||||
// - key: k1
|
||||
// body:
|
||||
// - key: a1
|
||||
// - operate: rename
|
||||
// headers:
|
||||
// - key: X-not-renamed
|
||||
// value: X-renamed
|
||||
// - operate: replace
|
||||
// headers:
|
||||
// - key: X-replace
|
||||
// value: replaced
|
||||
// - operate: add
|
||||
// headers:
|
||||
// - key: X-add-append
|
||||
// value: host-$1
|
||||
// host_pattern: ^(.*)\.com$
|
||||
// - operate: append
|
||||
// headers:
|
||||
// - key: X-add-append
|
||||
// value: path-$1
|
||||
// path_pattern: ^.*?\/(\w+)[\?]{0,1}.*$
|
||||
// body:
|
||||
// - key: a1-new
|
||||
// value: t1-$1-append
|
||||
// value_type: string
|
||||
// host_pattern: ^(.*)\.com$
|
||||
// - operate: map
|
||||
// headers:
|
||||
// - key: X-add-append
|
||||
// value: X-map
|
||||
// - operate: dedupe
|
||||
// headers:
|
||||
// - key: X-dedupe-first
|
||||
// value: RETAIN_FIRST
|
||||
// @End
|
||||
type TransformerConfig struct {
|
||||
// @Title 转换器类型
|
||||
// @Description 指定转换器类型，可选值为 request, response。
|
||||
typ string `yaml:"type"`
|
||||
|
||||
// @Title 转换规则
|
||||
// @Description 指定转换操作类型以及请求/响应头、请求查询参数、请求/响应体参数的转换规则
|
||||
rules []TransformRule `yaml:"rules"`
|
||||
|
||||
// this field is not exposed to the user and is used to store the request/response transformer instance
|
||||
trans Transformer `yaml:"-"`
|
||||
}
|
||||
|
||||
type TransformRule struct {
|
||||
// @Title 转换操作类型
|
||||
// @Description 指定转换操作类型，可选值为 remove, rename, replace, add, append, map, dedupe
|
||||
operate string `yaml:"operate"`
|
||||
|
||||
// @Title 请求/响应头转换规则
|
||||
// @Description 指定请求/响应头转换规则
|
||||
headers []Param `yaml:"headers"`
|
||||
|
||||
// @Title 请求查询参数转换规则
|
||||
// @Description 指定请求查询参数转换规则
|
||||
querys []Param `yaml:"querys"`
|
||||
|
||||
// @Title 请求/响应体参数转换规则
|
||||
// @Description 指定请求/响应体参数转换规则，请求体转换允许 content-type 为 application/json, application/x-www-form-urlencoded, multipart/form-data；响应体转换仅允许 content-type 为 application/json
|
||||
body []Param `yaml:"body"`
|
||||
}
|
||||
|
||||
type Param struct {
|
||||
// @Title 参数的键
|
||||
// @Description 指定键值对的键
|
||||
key string `yaml:"key"`
|
||||
|
||||
// @Title 参数的值
|
||||
// @Description 指定键值对的值，可能的含义有：空 (remove)，key (rename, map), value (replace, add, append), strategy (dedupe)
|
||||
value string `yaml:"value"`
|
||||
|
||||
// @Title 值类型
|
||||
// @Description 当 content-type=application/json 时，为请求/响应体参数指定值类型，可选值为 object, boolean, number, string(default)
|
||||
valueType string `yaml:"value_type"`
|
||||
|
||||
// @Title 请求主机名匹配规则
|
||||
// @Description 指定主机名匹配规则，当转换操作类型为 replace, add, append 时有效
|
||||
hostPattern string `yaml:"host_pattern"`
|
||||
|
||||
// @Title 请求路径匹配规则
|
||||
// @Description 指定路径匹配规则，当转换操作类型为 replace, add, append 时有效
|
||||
pathPattern string `yaml:"path_pattern"`
|
||||
}
|
||||
|
||||
func parseConfig(json gjson.Result, config *TransformerConfig, log wrapper.Log) (err error) {
|
||||
config.typ = strings.ToLower(json.Get("type").String())
|
||||
if config.typ != "request" && config.typ != "response" {
|
||||
return errors.Errorf("invalid transformer type %q", config.typ)
|
||||
}
|
||||
|
||||
config.rules = make([]TransformRule, 0)
|
||||
rules := json.Get("rules").Array()
|
||||
for _, r := range rules {
|
||||
var tRule TransformRule
|
||||
tRule.operate = strings.ToLower(r.Get("operate").String())
|
||||
if !isValidOperation(tRule.operate) {
|
||||
return errors.Errorf("invalid operate type %q", tRule.operate)
|
||||
}
|
||||
for _, h := range r.Get("headers").Array() {
|
||||
tRule.headers = append(tRule.headers, constructParam(&h, tRule.operate, ""))
|
||||
}
|
||||
for _, q := range r.Get("querys").Array() {
|
||||
tRule.querys = append(tRule.querys, constructParam(&q, tRule.operate, ""))
|
||||
}
|
||||
for _, b := range r.Get("body").Array() {
|
||||
valueType := strings.ToLower(b.Get("value_type").String())
|
||||
if valueType == "" { // default
|
||||
valueType = "string"
|
||||
}
|
||||
if !isValidJsonType(valueType) {
|
||||
return errors.Errorf("invalid body params type %q", valueType)
|
||||
}
|
||||
tRule.body = append(tRule.body, constructParam(&b, tRule.operate, valueType))
|
||||
}
|
||||
config.rules = append(config.rules, tRule)
|
||||
}
|
||||
|
||||
switch config.typ {
|
||||
case "request":
|
||||
config.trans, err = newRequestTransformer(config)
|
||||
case "response":
|
||||
config.trans, err = newResponseTransformer(config)
|
||||
}
|
||||
if err != nil {
|
||||
return errors.Wrapf(err, "failed to new %s transformer", config.typ)
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
func constructParam(item *gjson.Result, op, valueType string) Param {
|
||||
p := Param{
|
||||
key: item.Get("key").String(),
|
||||
value: item.Get("value").String(),
|
||||
valueType: valueType,
|
||||
}
|
||||
if op == "replace" || op == "add" || op == "append" {
|
||||
p.hostPattern = item.Get("host_pattern").String()
|
||||
p.pathPattern = item.Get("path_pattern").String()
|
||||
}
|
||||
return p
|
||||
}
|
||||
|
||||
func onHttpRequestHeaders(ctx wrapper.HttpContext, config TransformerConfig, log wrapper.Log) types.Action {
|
||||
// because it may be a response transformer, so the setting of host and path have to advance
|
||||
host, path := ctx.Host(), ctx.Path()
|
||||
ctx.SetContext("host", host)
|
||||
ctx.SetContext("path", path)
|
||||
|
||||
if config.typ == "response" {
|
||||
return types.ActionContinue
|
||||
}
|
||||
|
||||
log.Debug("on http request headers ...")
|
||||
|
||||
headers, err := proxywasm.GetHttpRequestHeaders()
|
||||
if err != nil {
|
||||
log.Warn("failed to get request headers")
|
||||
return types.ActionContinue
|
||||
}
|
||||
hs := convertHeaders(headers)
|
||||
if hs[":authority"] == nil {
|
||||
log.Warn(errGetRequestHost.Error())
|
||||
return types.ActionContinue
|
||||
}
|
||||
if hs[":path"] == nil {
|
||||
log.Warn(errGetRequestPath.Error())
|
||||
return types.ActionContinue
|
||||
}
|
||||
contentType := ""
|
||||
if hs["content-type"] != nil {
|
||||
contentType = hs["content-type"][0]
|
||||
}
|
||||
if config.trans.IsBodyChange() && isValidRequestContentType(contentType) {
|
||||
delete(hs, "content-length")
|
||||
ctx.SetContext("content-type", contentType)
|
||||
} else {
|
||||
ctx.DontReadRequestBody()
|
||||
}
|
||||
|
||||
if config.trans.IsHeaderChange() {
|
||||
if err = config.trans.TransformHeaders(host, path, hs); err != nil {
|
||||
log.Warnf("failed to transform request headers: %v", err)
|
||||
return types.ActionContinue
|
||||
}
|
||||
}
|
||||
|
||||
if config.trans.IsQueryChange() {
|
||||
qs, err := parseQueryByPath(path)
|
||||
if err != nil {
|
||||
log.Warnf("failed to parse query params by path: %v", err)
|
||||
return types.ActionContinue
|
||||
}
|
||||
if err = config.trans.TransformQuerys(host, path, qs); err != nil {
|
||||
log.Warnf("failed to transform request query params: %v", err)
|
||||
return types.ActionContinue
|
||||
}
|
||||
path, err = constructPath(path, qs)
|
||||
if err != nil {
|
||||
log.Warnf("failed to construct path: %v", err)
|
||||
return types.ActionContinue
|
||||
}
|
||||
hs[":path"] = []string{path}
|
||||
}
|
||||
|
||||
headers = reconvertHeaders(hs)
|
||||
if err = proxywasm.ReplaceHttpRequestHeaders(headers); err != nil {
|
||||
log.Warnf("failed to replace request headers: %v", err)
|
||||
return types.ActionContinue
|
||||
}
|
||||
|
||||
return types.ActionContinue
|
||||
}
|
||||
|
||||
func onHttpRequestBody(ctx wrapper.HttpContext, config TransformerConfig, body []byte, log wrapper.Log) types.Action {
|
||||
if config.typ == "response" || !config.trans.IsBodyChange() {
|
||||
return types.ActionContinue
|
||||
}
|
||||
|
||||
log.Debug("on http request body ...")
|
||||
|
||||
host, path, err := getHostAndPathFromHttpCtx(ctx)
|
||||
if err != nil {
|
||||
log.Warn(err.Error())
|
||||
return types.ActionContinue
|
||||
}
|
||||
contentType, ok := ctx.GetContext("content-type").(string)
|
||||
if !ok {
|
||||
log.Warn(errGetContentType.Error())
|
||||
return types.ActionContinue
|
||||
}
|
||||
structuredBody, err := parseBody(contentType, body)
|
||||
if err != nil {
|
||||
if !errors.Is(err, errEmptyBody) {
|
||||
log.Warnf("failed to parse request body: %v", err)
|
||||
}
|
||||
log.Debug("request body is empty")
|
||||
return types.ActionContinue
|
||||
}
|
||||
|
||||
if err = config.trans.TransformBody(host, path, structuredBody); err != nil {
|
||||
log.Warnf("failed to transform request body: %v", err)
|
||||
return types.ActionContinue
|
||||
}
|
||||
|
||||
body, err = constructBody(contentType, structuredBody)
|
||||
if err != nil {
|
||||
log.Warnf("failed to construct request body: %v", err)
|
||||
return types.ActionContinue
|
||||
}
|
||||
if err = proxywasm.ReplaceHttpRequestBody(body); err != nil {
|
||||
log.Warnf("failed to replace request body: %v", err)
|
||||
return types.ActionContinue
|
||||
}
|
||||
|
||||
return types.ActionContinue
|
||||
}
|
||||
|
||||
func onHttpResponseHeaders(ctx wrapper.HttpContext, config TransformerConfig, log wrapper.Log) types.Action {
|
||||
if config.typ == "request" {
|
||||
return types.ActionContinue
|
||||
}
|
||||
|
||||
log.Debug("on http response headers ...")
|
||||
|
||||
host, path, err := getHostAndPathFromHttpCtx(ctx)
|
||||
if err != nil {
|
||||
log.Warn(err.Error())
|
||||
return types.ActionContinue
|
||||
}
|
||||
headers, err := proxywasm.GetHttpResponseHeaders()
|
||||
if err != nil {
|
||||
log.Warnf("failed to get response headers: %v", err)
|
||||
return types.ActionContinue
|
||||
}
|
||||
hs := convertHeaders(headers)
|
||||
contentType := ""
|
||||
if hs["content-type"] != nil {
|
||||
contentType = hs["content-type"][0]
|
||||
}
|
||||
if config.trans.IsBodyChange() && isValidResponseContentType(contentType) {
|
||||
delete(hs, "content-length")
|
||||
ctx.SetContext("content-type", contentType)
|
||||
} else {
|
||||
ctx.DontReadResponseBody()
|
||||
}
|
||||
|
||||
if config.trans.IsHeaderChange() {
|
||||
if err = config.trans.TransformHeaders(host, path, hs); err != nil {
|
||||
log.Warnf("failed to transform response headers: %v", err)
|
||||
return types.ActionContinue
|
||||
}
|
||||
}
|
||||
|
||||
headers = reconvertHeaders(hs)
|
||||
if err = proxywasm.ReplaceHttpResponseHeaders(headers); err != nil {
|
||||
log.Warnf("failed to replace response headers: %v", err)
|
||||
return types.ActionContinue
|
||||
}
|
||||
|
||||
return types.ActionContinue
|
||||
}
|
||||
|
||||
func onHttpResponseBody(ctx wrapper.HttpContext, config TransformerConfig, body []byte, log wrapper.Log) types.Action {
|
||||
if config.typ == "request" || !config.trans.IsBodyChange() {
|
||||
return types.ActionContinue
|
||||
}
|
||||
|
||||
log.Debug("on http response body ...")
|
||||
|
||||
host, path, err := getHostAndPathFromHttpCtx(ctx)
|
||||
if err != nil {
|
||||
log.Warn(err.Error())
|
||||
return types.ActionContinue
|
||||
}
|
||||
contentType, ok := ctx.GetContext("content-type").(string)
|
||||
if !ok {
|
||||
log.Warn(errGetContentType.Error())
|
||||
return types.ActionContinue
|
||||
}
|
||||
structuredBody, err := parseBody(contentType, body)
|
||||
if err != nil {
|
||||
if !errors.Is(err, errEmptyBody) {
|
||||
log.Warnf("failed to parse response body: %v", err)
|
||||
}
|
||||
log.Debug("response body is empty")
|
||||
return types.ActionContinue
|
||||
}
|
||||
|
||||
if err = config.trans.TransformBody(host, path, structuredBody); err != nil {
|
||||
log.Warnf("failed to transform response body: %v", err)
|
||||
return types.ActionContinue
|
||||
}
|
||||
|
||||
body, err = constructBody(contentType, structuredBody)
|
||||
if err != nil {
|
||||
log.Warnf("failed to construct response body: %v", err)
|
||||
return types.ActionContinue
|
||||
}
|
||||
if err = proxywasm.ReplaceHttpResponseBody(body); err != nil {
|
||||
log.Warnf("failed to replace response body: %v", err)
|
||||
return types.ActionContinue
|
||||
}
|
||||
|
||||
return types.ActionContinue
|
||||
}
|
||||
|
||||
func getHostAndPathFromHttpCtx(ctx wrapper.HttpContext) (host, path string, err error) {
|
||||
host, ok := ctx.GetContext("host").(string)
|
||||
if !ok {
|
||||
return "", "", errGetRequestHost
|
||||
}
|
||||
path, ok = ctx.GetContext("path").(string)
|
||||
if !ok {
|
||||
return "", "", errGetRequestPath
|
||||
}
|
||||
return host, path, nil
|
||||
}
|
||||
|
||||
type Transformer interface {
|
||||
TransformHeaders(host, path string, hs map[string][]string) error
|
||||
TransformQuerys(host, path string, qs map[string][]string) error
|
||||
TransformBody(host, path string, body interface{}) error
|
||||
IsHeaderChange() bool
|
||||
IsQueryChange() bool
|
||||
IsBodyChange() bool
|
||||
}
|
||||
|
||||
var _ Transformer = (*requestTransformer)(nil)
|
||||
var _ Transformer = (*responseTransformer)(nil)
|
||||
|
||||
type requestTransformer struct {
|
||||
headerHandler *kvHandler
|
||||
queryHandler *kvHandler
|
||||
bodyHandler *requestBodyHandler
|
||||
isHeaderChange bool
|
||||
isQueryChange bool
|
||||
isBodyChange bool
|
||||
}
|
||||
|
||||
func newRequestTransformer(config *TransformerConfig) (Transformer, error) {
|
||||
headerKvtGroup, isHeaderChange, err := newKvtGroup(config.rules, "headers")
|
||||
if err != nil {
|
||||
return nil, errors.Wrap(err, "failed to new kvt group for headers")
|
||||
}
|
||||
queryKvtGroup, isQueryChange, err := newKvtGroup(config.rules, "querys")
|
||||
if err != nil {
|
||||
return nil, errors.Wrap(err, "failed to new kvt group for querys")
|
||||
}
|
||||
bodyKvtGroup, isBodyChange, err := newKvtGroup(config.rules, "body")
|
||||
if err != nil {
|
||||
return nil, errors.Wrap(err, "failed to new kvt group for body")
|
||||
}
|
||||
return &requestTransformer{
|
||||
headerHandler: &kvHandler{headerKvtGroup},
|
||||
queryHandler: &kvHandler{queryKvtGroup},
|
||||
bodyHandler: &requestBodyHandler{
|
||||
formDataHandler: &kvHandler{bodyKvtGroup},
|
||||
jsonHandler: &jsonHandler{bodyKvtGroup},
|
||||
},
|
||||
isHeaderChange: isHeaderChange,
|
||||
isQueryChange: isQueryChange,
|
||||
isBodyChange: isBodyChange,
|
||||
}, nil
|
||||
}
|
||||
|
||||
func (t requestTransformer) TransformHeaders(host, path string, hs map[string][]string) error {
|
||||
return t.headerHandler.handle(host, path, hs)
|
||||
}
|
||||
|
||||
func (t requestTransformer) TransformQuerys(host, path string, qs map[string][]string) error {
|
||||
return t.queryHandler.handle(host, path, qs)
|
||||
}
|
||||
|
||||
func (t requestTransformer) TransformBody(host, path string, body interface{}) error {
|
||||
switch body.(type) {
|
||||
case map[string][]string:
|
||||
return t.bodyHandler.formDataHandler.handle(host, path, body.(map[string][]string))
|
||||
|
||||
case map[string]interface{}:
|
||||
m := body.(map[string]interface{})
|
||||
newBody, err := t.bodyHandler.handle(host, path, m["body"].([]byte))
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
m["body"] = newBody
|
||||
|
||||
default:
|
||||
return errBodyType
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
func (t requestTransformer) IsHeaderChange() bool { return t.isHeaderChange }
|
||||
func (t requestTransformer) IsQueryChange() bool { return t.isQueryChange }
|
||||
func (t requestTransformer) IsBodyChange() bool { return t.isBodyChange }
|
||||
|
||||
type responseTransformer struct {
|
||||
headerHandler *kvHandler
|
||||
bodyHandler *responseBodyHandler
|
||||
isHeaderChange bool
|
||||
isBodyChange bool
|
||||
}
|
||||
|
||||
func newResponseTransformer(config *TransformerConfig) (Transformer, error) {
|
||||
headerKvtGroup, isHeaderChange, err := newKvtGroup(config.rules, "headers")
|
||||
if err != nil {
|
||||
return nil, errors.Wrap(err, "failed to new kvt group for headers")
|
||||
}
|
||||
bodyKvtGroup, isBodyChange, err := newKvtGroup(config.rules, "body")
|
||||
if err != nil {
|
||||
return nil, errors.Wrap(err, "failed to new kvt group for body")
|
||||
}
|
||||
return &responseTransformer{
|
||||
headerHandler: &kvHandler{headerKvtGroup},
|
||||
bodyHandler: &responseBodyHandler{&jsonHandler{bodyKvtGroup}},
|
||||
isHeaderChange: isHeaderChange,
|
||||
isBodyChange: isBodyChange,
|
||||
}, nil
|
||||
}
|
||||
|
||||
func (t responseTransformer) TransformHeaders(host, path string, hs map[string][]string) error {
|
||||
return t.headerHandler.handle(host, path, hs)
|
||||
}
|
||||
|
||||
func (t responseTransformer) TransformQuerys(host, path string, qs map[string][]string) error {
|
||||
// the response does not need to transform the query params, always returns nil
|
||||
return nil
|
||||
}
|
||||
|
||||
func (t responseTransformer) TransformBody(host, path string, body interface{}) error {
|
||||
switch body.(type) {
|
||||
case map[string]interface{}:
|
||||
m := body.(map[string]interface{})
|
||||
newBody, err := t.bodyHandler.handle(host, path, m["body"].([]byte))
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
m["body"] = newBody
|
||||
|
||||
default:
|
||||
return errBodyType
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
func (t responseTransformer) IsHeaderChange() bool { return t.isHeaderChange }
|
||||
func (t responseTransformer) IsQueryChange() bool { return false } // the response does not need to transform the query params, always returns false
|
||||
func (t responseTransformer) IsBodyChange() bool { return t.isBodyChange }
|
||||
|
||||
type requestBodyHandler struct {
|
||||
formDataHandler *kvHandler
|
||||
*jsonHandler
|
||||
}
|
||||
|
||||
type responseBodyHandler struct {
|
||||
*jsonHandler
|
||||
}
|
||||
|
||||
type kvHandler struct {
|
||||
*kvtGroup
|
||||
}
|
||||
|
||||
type jsonHandler struct {
|
||||
*kvtGroup
|
||||
}
|
||||
|
||||
func (h kvHandler) handle(host, path string, kvs map[string][]string) error {
|
||||
// order: remove → rename → replace → add → append → map → dedupe
|
||||
|
||||
// remove
|
||||
for _, key := range h.remove {
|
||||
delete(kvs, key)
|
||||
}
|
||||
|
||||
// rename: 若指定 oldKey 不存在则无操作；否则将 oldKey 的值追加给 newKey，并删除 oldKey:value
|
||||
for _, item := range h.rename {
|
||||
oldKey, newKey := item.key, item.value
|
||||
if ovs, ok := kvs[oldKey]; ok {
|
||||
kvs[newKey] = append(kvs[newKey], ovs...)
|
||||
delete(kvs, oldKey)
|
||||
}
|
||||
}
|
||||
|
||||
// replace: 若指定 key 不存在，则无操作；否则替换 value 为 newValue
|
||||
for _, item := range h.replace {
|
||||
key, newValue := item.key, item.value
|
||||
if _, ok := kvs[key]; !ok {
|
||||
continue
|
||||
}
|
||||
if item.reg != nil {
|
||||
newValue = item.reg.matchAndReplace(newValue, host, path)
|
||||
}
|
||||
kvs[item.key] = []string{newValue}
|
||||
}
|
||||
|
||||
// add: 若指定 key 存在则无操作；否则添加 key:value
|
||||
for _, item := range h.add {
|
||||
key, value := item.key, item.value
|
||||
if _, ok := kvs[key]; ok {
|
||||
continue
|
||||
}
|
||||
if item.reg != nil {
|
||||
value = item.reg.matchAndReplace(value, host, path)
|
||||
}
|
||||
kvs[key] = []string{value}
|
||||
}
|
||||
|
||||
// append: 若指定 key 存在，则追加同名 kv；否则相当于添加操作
|
||||
for _, item := range h.append {
|
||||
key, appendValue := item.key, item.value
|
||||
if item.reg != nil {
|
||||
appendValue = item.reg.matchAndReplace(appendValue, host, path)
|
||||
}
|
||||
kvs[key] = append(kvs[key], appendValue)
|
||||
}
|
||||
|
||||
// map: 若指定 fromKey 不存在则无操作；否则将 fromKey 的值映射给 toKey 的值
|
||||
for _, item := range h.map_ {
|
||||
fromKey, toKey := item.key, item.value
|
||||
if vs, ok := kvs[fromKey]; ok {
|
||||
kvs[toKey] = vs
|
||||
}
|
||||
}
|
||||
|
||||
// dedupe: 根据 strategy 去重：RETAIN_UNIQUE 保留所有唯一值，RETAIN_LAST 保留最后一个值，RETAIN_FIRST 保留第一个值 (default)
|
||||
for _, item := range h.dedupe {
|
||||
key, strategy := item.key, item.value
|
||||
switch strings.ToUpper(strategy) {
|
||||
case "RETAIN_UNIQUE":
|
||||
uniSet, uniques := make(map[string]struct{}), make([]string, 0)
|
||||
for _, v := range kvs[key] {
|
||||
if _, ok := uniSet[v]; !ok {
|
||||
uniSet[v] = struct{}{}
|
||||
uniques = append(uniques, v)
|
||||
}
|
||||
}
|
||||
kvs[key] = uniques
|
||||
|
||||
case "RETAIN_LAST":
|
||||
if vs, ok := kvs[key]; ok && len(vs) >= 1 {
|
||||
kvs[key] = vs[len(vs)-1:]
|
||||
}
|
||||
|
||||
case "RETAIN_FIRST":
|
||||
fallthrough
|
||||
default:
|
||||
if vs, ok := kvs[key]; ok && len(vs) >= 1 {
|
||||
kvs[key] = vs[:1]
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
func (h jsonHandler) handle(host, path string, oriData []byte) (data []byte, err error) {
|
||||
// order: remove → rename → replace → add → append → map → dedupe
|
||||
if !gjson.ValidBytes(oriData) {
|
||||
return nil, errors.New("invalid json body")
|
||||
}
|
||||
data = oriData
|
||||
|
||||
// remove
|
||||
for _, key := range h.remove {
|
||||
if data, err = sjson.DeleteBytes(data, key); err != nil {
|
||||
return nil, errors.Wrap(err, errRemove.Error())
|
||||
}
|
||||
}
|
||||
|
||||
// rename: 若指定 oldKey 不存在则无操作；否则将 oldKey 的值追加给 newKey，并删除 oldKey:value
|
||||
for _, item := range h.rename {
|
||||
oldKey, newKey := item.key, item.value
|
||||
value := gjson.GetBytes(data, oldKey)
|
||||
if !value.Exists() {
|
||||
continue
|
||||
}
|
||||
if data, err = sjson.SetBytes(data, newKey, value.Value()); err != nil {
|
||||
return nil, errors.Wrap(err, errRename.Error())
|
||||
}
|
||||
if data, err = sjson.DeleteBytes(data, oldKey); err != nil {
|
||||
return nil, errors.Wrap(err, errRename.Error())
|
||||
}
|
||||
}
|
||||
|
||||
// replace: 若指定 key 不存在，则无操作；否则替换 value 为 newValue
|
||||
for _, item := range h.replace {
|
||||
key, value, valueType := item.key, item.value, item.typ
|
||||
if !gjson.GetBytes(data, key).Exists() {
|
||||
continue
|
||||
}
|
||||
if valueType == "string" && item.reg != nil {
|
||||
value = item.reg.matchAndReplace(value, host, path)
|
||||
}
|
||||
newValue, err := convertByJsonType(valueType, value)
|
||||
if err != nil {
|
||||
return nil, errors.Wrap(err, errReplace.Error())
|
||||
}
|
||||
if data, err = sjson.SetBytes(data, key, newValue); err != nil {
|
||||
return nil, errors.Wrap(err, errReplace.Error())
|
||||
}
|
||||
}
|
||||
|
||||
// add: 若指定 key 存在则无操作；否则添加 key:value
|
||||
for _, item := range h.add {
|
||||
key, value, valueType := item.key, item.value, item.typ
|
||||
if gjson.GetBytes(data, key).Exists() {
|
||||
continue
|
||||
}
|
||||
if valueType == "string" && item.reg != nil {
|
||||
value = item.reg.matchAndReplace(value, host, path)
|
||||
}
|
||||
newValue, err := convertByJsonType(valueType, value)
|
||||
if err != nil {
|
||||
return nil, errors.Wrap(err, errAdd.Error())
|
||||
}
|
||||
if data, err = sjson.SetBytes(data, key, newValue); err != nil {
|
||||
return nil, errors.Wrap(err, errAdd.Error())
|
||||
}
|
||||
}
|
||||
|
||||
// append: 若指定 key 存在，则追加同名 kv；否则相当于添加操作
|
||||
// 当原本的 value 为数组时，追加；当原本的 value 不为数组时，将原本的 value 和 appendValue 组成数组
|
||||
for _, item := range h.append {
|
||||
key, value, valueType := item.key, item.value, item.typ
|
||||
if valueType == "string" && item.reg != nil {
|
||||
value = item.reg.matchAndReplace(value, host, path)
|
||||
}
|
||||
appendValue, err := convertByJsonType(valueType, value)
|
||||
if err != nil {
|
||||
return nil, errors.Wrapf(err, errAppend.Error())
|
||||
}
|
||||
oldValue := gjson.GetBytes(data, key)
|
||||
if !oldValue.Exists() {
|
||||
if data, err = sjson.SetBytes(data, key, appendValue); err != nil { // key: appendValue
|
||||
return nil, errors.Wrap(err, errAppend.Error())
|
||||
}
|
||||
continue
|
||||
}
|
||||
|
||||
// oldValue exists
|
||||
if oldValue.IsArray() {
|
||||
if len(oldValue.Array()) == 0 {
|
||||
if data, err = sjson.SetBytes(data, key, []interface{}{appendValue}); err != nil { // key: [appendValue]
|
||||
return nil, errors.Wrap(err, errAppend.Error())
|
||||
}
|
||||
continue
|
||||
}
|
||||
|
||||
// len(oldValue.Array()) != 0
|
||||
oldValues := make([]interface{}, 0, len(oldValue.Array())+1)
|
||||
for _, val := range oldValue.Array() {
|
||||
oldValues = append(oldValues, val.Value())
|
||||
}
|
||||
if data, err = sjson.SetBytes(data, key, append(oldValues, appendValue)); err != nil { // key: [oldValue..., appendValue]
|
||||
return nil, errors.Wrap(err, errAppend.Error())
|
||||
}
|
||||
continue
|
||||
}
|
||||
|
||||
// oldValue is not array
|
||||
if data, err = sjson.SetBytes(data, key, []interface{}{oldValue.Value(), appendValue}); err != nil { // key: [oldValue, appendValue]
|
||||
return nil, errors.Wrap(err, errAppend.Error())
|
||||
}
|
||||
}
|
||||
|
||||
// map: 若指定 fromKey 不存在则无操作；否则将 fromKey 的值映射给 toKey 的值
|
||||
for _, item := range h.map_ {
|
||||
fromKey, toKey := item.key, item.value
|
||||
fromValue := gjson.GetBytes(data, fromKey)
|
||||
if !fromValue.Exists() {
|
||||
continue
|
||||
}
|
||||
if data, err = sjson.SetBytes(data, toKey, fromValue.Value()); err != nil {
|
||||
return nil, errors.Wrap(err, errMap.Error())
|
||||
}
|
||||
}
|
||||
|
||||
// dedupe: 根据 strategy 去重：RETAIN_UNIQUE 保留所有唯一值，RETAIN_LAST 保留最后一个值，RETAIN_FIRST 保留第一个值 (default)
|
||||
for _, item := range h.dedupe {
|
||||
key, strategy := item.key, item.value
|
||||
value := gjson.GetBytes(data, key)
|
||||
if !value.Exists() || !value.IsArray() {
|
||||
continue
|
||||
}
|
||||
|
||||
// value is array
|
||||
values := value.Array()
|
||||
if len(values) == 0 {
|
||||
continue
|
||||
}
|
||||
|
||||
var dedupedVal interface{}
|
||||
switch strings.ToUpper(strategy) {
|
||||
case "RETAIN_UNIQUE":
|
||||
uniSet, uniques := make(map[string]struct{}), make([]interface{}, 0)
|
||||
for _, v := range values {
|
||||
vstr := v.String()
|
||||
if _, ok := uniSet[vstr]; !ok {
|
||||
uniSet[vstr] = struct{}{}
|
||||
uniques = append(uniques, v.Value())
|
||||
}
|
||||
}
|
||||
if len(uniques) == 1 {
|
||||
dedupedVal = uniques[0] // key: uniques[0]
|
||||
} else if len(uniques) > 1 {
|
||||
dedupedVal = uniques // key: [uniques...]
|
||||
}
|
||||
|
||||
case "RETAIN_LAST":
|
||||
dedupedVal = values[len(values)-1].Value() // key: last
|
||||
|
||||
case "RETAIN_FIRST":
|
||||
fallthrough
|
||||
default:
|
||||
dedupedVal = values[0].Value() // key: first
|
||||
}
|
||||
|
||||
if dedupedVal == nil {
|
||||
continue
|
||||
}
|
||||
if data, err = sjson.SetBytes(data, key, dedupedVal); err != nil {
|
||||
return nil, errors.Wrap(err, errDedupe.Error())
|
||||
}
|
||||
}
|
||||
|
||||
return data, nil
|
||||
}
|
||||
|
||||
type kvtGroup struct {
|
||||
remove []string // key
|
||||
rename []kvt // oldKey:newKey
|
||||
replace []kvtReg // key:newValue
|
||||
add []kvtReg // newKey:newValue
|
||||
append []kvtReg // key:appendValue
|
||||
map_ []kvt // fromKey:toKey
|
||||
dedupe []kvt // key:strategy
|
||||
}
|
||||
|
||||
func newKvtGroup(rules []TransformRule, typ string) (g *kvtGroup, isChange bool, err error) {
|
||||
g = &kvtGroup{}
|
||||
for _, r := range rules {
|
||||
var prams []Param
|
||||
switch typ {
|
||||
case "headers":
|
||||
prams = r.headers
|
||||
case "querys":
|
||||
prams = r.querys
|
||||
case "body":
|
||||
prams = r.body
|
||||
}
|
||||
|
||||
for _, p := range prams {
|
||||
switch r.operate {
|
||||
case "remove":
|
||||
key := p.key
|
||||
if typ == "headers" {
|
||||
key = strings.ToLower(key)
|
||||
}
|
||||
g.remove = append(g.remove, key)
|
||||
|
||||
case "rename", "map", "dedupe":
|
||||
var kt kvt
|
||||
kt.key, kt.value = p.key, p.value
|
||||
if typ == "headers" {
|
||||
kt.key = strings.ToLower(kt.key)
|
||||
if r.operate == "rename" || r.operate == "map" {
|
||||
kt.value = strings.ToLower(kt.value)
|
||||
}
|
||||
}
|
||||
if typ == "body" {
|
||||
kt.typ = p.valueType
|
||||
}
|
||||
switch r.operate {
|
||||
case "rename":
|
||||
g.rename = append(g.rename, kt)
|
||||
case "map":
|
||||
g.map_ = append(g.map_, kt)
|
||||
case "dedupe":
|
||||
g.dedupe = append(g.dedupe, kt)
|
||||
}
|
||||
|
||||
case "replace", "add", "append":
|
||||
var kr kvtReg
|
||||
kr.key, kr.value = p.key, p.value
|
||||
if typ == "headers" {
|
||||
kr.key = strings.ToLower(kr.key)
|
||||
}
|
||||
if p.hostPattern != "" || p.pathPattern != "" {
|
||||
kr.reg, err = newReg(p.hostPattern, p.pathPattern)
|
||||
if err != nil {
|
||||
return nil, false, errors.Wrap(err, "failed to new reg")
|
||||
}
|
||||
}
|
||||
if typ == "body" {
|
||||
kr.typ = p.valueType
|
||||
}
|
||||
switch r.operate {
|
||||
case "replace":
|
||||
g.replace = append(g.replace, kr)
|
||||
case "add":
|
||||
g.add = append(g.add, kr)
|
||||
case "append":
|
||||
g.append = append(g.append, kr)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
isChange = len(g.remove) != 0 ||
|
||||
len(g.rename) != 0 || len(g.replace) != 0 ||
|
||||
len(g.add) != 0 || len(g.append) != 0 ||
|
||||
len(g.map_) != 0 || len(g.dedupe) != 0
|
||||
|
||||
return g, isChange, nil
|
||||
}
|
||||
|
||||
type kvtReg struct {
|
||||
kvt
|
||||
*reg
|
||||
}
|
||||
|
||||
type kvt struct {
|
||||
key string
|
||||
value string
|
||||
typ string
|
||||
}
|
||||
|
||||
type reg struct {
|
||||
hostReg *regexp.Regexp
|
||||
pathReg *regexp.Regexp
|
||||
}
|
||||
|
||||
// you can only choose one between host and path
|
||||
func newReg(hostPatten, pathPatten string) (r *reg, err error) {
|
||||
r = ®{}
|
||||
if hostPatten != "" {
|
||||
r.hostReg, err = regexp.Compile(hostPatten)
|
||||
return
|
||||
}
|
||||
if pathPatten != "" {
|
||||
r.pathReg, err = regexp.Compile(pathPatten)
|
||||
return
|
||||
}
|
||||
return
|
||||
}
|
||||
|
||||
func (r reg) matchAndReplace(value, host, path string) string {
|
||||
if r.hostReg != nil && r.hostReg.MatchString(host) {
|
||||
return r.hostReg.ReplaceAllString(host, value)
|
||||
}
|
||||
if r.pathReg != nil && r.pathReg.MatchString(path) {
|
||||
return r.pathReg.ReplaceAllString(path, value)
|
||||
}
|
||||
return value
|
||||
}
|
||||
Reference in New Issue
Block a user