[#371] Add custom Source IP header configuration

Signed-off-by: Marina Biryukova <m.biryukova@yadro.com>

api/middleware/reqinfo.go

@@ -83,17 +83,24 @@ var (
 )
 
 // NewReqInfo returns new ReqInfo based on parameters.
-func NewReqInfo(w http.ResponseWriter, r *http.Request, req ObjectRequest) *ReqInfo {
-	return &ReqInfo{
+func NewReqInfo(w http.ResponseWriter, r *http.Request, req ObjectRequest, sourceIPHeader string) *ReqInfo {
+	reqInfo := &ReqInfo{
 		API:          req.Method,
 		BucketName:   req.Bucket,
 		ObjectName:   req.Object,
 		UserAgent:    r.UserAgent(),
-		RemoteHost:   getSourceIP(r),
 		RequestID:    GetRequestID(w),
 		DeploymentID: deploymentID.String(),
 		URL:          r.URL,
 	}
+
+	if sourceIPHeader != "" {
+		reqInfo.RemoteHost = r.Header.Get(sourceIPHeader)
+	} else {
+		reqInfo.RemoteHost = getSourceIP(r)
+	}
+
+	return reqInfo
 }
 
 // AppendTags -- appends key/val to ReqInfo.tags.
@@ -193,6 +200,7 @@ func GetReqLog(ctx context.Context) *zap.Logger {
 type RequestSettings interface {
 	NamespaceHeader() string
 	ResolveNamespaceAlias(string) string
+	SourceIPHeader() string
 }
 
 func Request(log *zap.Logger, settings RequestSettings) Func {
@@ -211,7 +219,7 @@ func Request(log *zap.Logger, settings RequestSettings) Func {
 
 			// set request info into context
 			// bucket name and object will be set in reqInfo later (limitation of go-chi)
-			reqInfo := NewReqInfo(w, r, ObjectRequest{})
+			reqInfo := NewReqInfo(w, r, ObjectRequest{}, settings.SourceIPHeader())
 			reqInfo.Namespace = settings.ResolveNamespaceAlias(r.Header.Get(settings.NamespaceHeader()))
 			r = r.WithContext(SetReqInfo(r.Context(), reqInfo))
 
@@ -317,11 +325,14 @@ func getSourceIP(r *http.Request) string {
 		}
 	}
 
-	if addr != "" {
-		return addr
+	if addr == "" {
+		addr = r.RemoteAddr
 	}
 
 	// Default to remote address if headers not set.
-	addr, _, _ = net.SplitHostPort(r.RemoteAddr)
-	return addr
+	raddr, _, _ := net.SplitHostPort(addr)
+	if raddr == "" {
+		return addr
+	}
+	return raddr
 }