Add content-type to header2body plugin

header2body.go

@@ -3,6 +3,7 @@ package rzluramartian
 import (
 	"bytes"
 	"encoding/json"
+	"fmt"
 	"io/ioutil"
 	"net/http"
 
@@ -12,10 +13,12 @@ import (
 type (
 	HeaderModifierConfig struct {
 		KeysToExtract []string `json:"keys_to_extract"`
+		ContentType   string   `json:"content_type"`
 	}
 
 	Header2BodyModifier struct {
 		keysToExtract []string
+		ContentType   string
 	}
 )
 
@@ -27,44 +30,55 @@ func headerModifierFromJSON(b []byte) (*parse.Result, error) {
 
 	mod := &Header2BodyModifier{
 		keysToExtract: cfg.KeysToExtract,
+		ContentType:   cfg.ContentType,
 	}
 	return parse.NewResult(mod, []parse.ModifierType{parse.Request})
 }
 
 func (m *Header2BodyModifier) ModifyRequest(req *http.Request) error {
 	var buf []byte
+
 	if req.Body != nil {
 		body, err := ioutil.ReadAll(req.Body)
 		if err != nil {
 			return err
 		}
 
-		data := make(map[string]interface{})
-		err = json.Unmarshal(body, &data)
-		if err != nil {
-			return err
-		}
+		switch m.ContentType {
+		case _contentType_applicationJSON:
+			data := make(map[string]interface{})
+			json.Unmarshal(body, &data) // Skip error even if it is failed
 
-		for _, k := range m.keysToExtract {
-			data[k] = req.Header.Get(k)
-			req.Header.Del(k)
-		}
+			for _, k := range m.keysToExtract {
+				data[k] = req.Header.Get(k)
+				req.Header.Del(k)
+			}
 
-		buf, err = json.Marshal(data)
-		if err != nil {
-			return err
+			buf, err = json.Marshal(data)
+			if err != nil {
+				return err
+			}
+		default:
+			return fmt.Errorf("unsupport content-type")
 		}
+
 	} else {
-		data := make(map[string]interface{})
-		for _, k := range m.keysToExtract {
-			data[k] = req.Header.Get(k)
-			req.Header.Del(k)
-		}
+		switch m.ContentType {
+		case _contentType_applicationJSON:
+			data := make(map[string]interface{})
 
-		var err error
-		buf, err = json.Marshal(data)
-		if err != nil {
-			return err
+			for _, k := range m.keysToExtract {
+				data[k] = req.Header.Get(k)
+				req.Header.Del(k)
+			}
+
+			var err error
+			buf, err = json.Marshal(data)
+			if err != nil {
+				return err
+			}
+		default:
+			return fmt.Errorf("unsupport content-type")
 		}
 	}
 	req.ContentLength = int64(len(buf))