initial import

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

go.mod

@@ -0,0 +1,5 @@
+module go.unistack.org/micro-wrapper-metadata/v4
+
+go 1.20
+
+require go.unistack.org/micro/v4 v4.0.17

go.sum

@@ -0,0 +1,2 @@
+go.unistack.org/micro/v4 v4.0.17 h1:mF7uM+J4ILdG+1fcwzKYCwDlxhdbF/e1WnGzKKLnIXc=
+go.unistack.org/micro/v4 v4.0.17/go.mod h1:ZDgU9931vm2l7X6RN/6UuwRIVp24GRdmQ7dKmegArk4=

metadata.go

@@ -0,0 +1,89 @@
+package wrappermetadata
+
+import (
+	"context"
+
+	"go.unistack.org/micro/v4/client"
+	"go.unistack.org/micro/v4/metadata"
+	"go.unistack.org/micro/v4/options"
+	"go.unistack.org/micro/v4/server"
+)
+
+type wrapper struct {
+	client.Client
+	exclude []string
+}
+
+func NewClientWrapper(exclude ...string) client.Wrapper {
+	return func(c client.Client) client.Client {
+		handler := &wrapper{
+			Client:  c,
+			exclude: exclude,
+		}
+		return handler
+	}
+}
+
+func NewClientCallWrapper(exclude ...string) client.CallWrapper {
+	return func(fn client.CallFunc) client.CallFunc {
+		return func(ctx context.Context, addr string, req client.Request, rsp interface{}, opts client.CallOptions) error {
+			if exclude == nil {
+				return fn(ctx, addr, req, rsp, opts)
+			}
+			if imd, iok := metadata.FromIncomingContext(ctx); iok && imd != nil {
+				omd, ook := metadata.FromOutgoingContext(ctx)
+				if !ook || omd == nil {
+					omd = metadata.New(len(imd))
+				}
+				ctx = metadata.NewOutgoingContext(ctx, metadata.Merge(omd, metadata.Copy(imd, exclude...), false))
+			}
+			return fn(ctx, addr, req, rsp, opts)
+		}
+	}
+}
+
+func (w *wrapper) Call(ctx context.Context, req client.Request, rsp interface{}, opts ...options.Option) error {
+	if w.exclude == nil {
+		return w.Client.Call(ctx, req, rsp, opts...)
+	}
+	if imd, iok := metadata.FromIncomingContext(ctx); iok && imd != nil {
+		omd, ook := metadata.FromOutgoingContext(ctx)
+		if !ook || omd == nil {
+			omd = metadata.New(len(imd))
+		}
+		ctx = metadata.NewOutgoingContext(ctx, metadata.Merge(omd, metadata.Copy(imd, w.exclude...), false))
+	}
+	return w.Client.Call(ctx, req, rsp, opts...)
+}
+
+func (w *wrapper) Stream(ctx context.Context, req client.Request, opts ...options.Option) (client.Stream, error) {
+	if w.exclude == nil {
+		return w.Client.Stream(ctx, req, opts...)
+	}
+	if imd, iok := metadata.FromIncomingContext(ctx); iok && imd != nil {
+		omd, ook := metadata.FromOutgoingContext(ctx)
+		if !ook || omd == nil {
+			omd = metadata.New(len(imd))
+		}
+		ctx = metadata.NewOutgoingContext(ctx, metadata.Merge(omd, metadata.Copy(imd, w.exclude...), false))
+	}
+	return w.Client.Stream(ctx, req, opts...)
+}
+
+func NewServerHandlerWrapper(exclude ...string) server.HandlerWrapper {
+	return func(fn server.HandlerFunc) server.HandlerFunc {
+		return func(ctx context.Context, req server.Request, rsp interface{}) error {
+			if exclude == nil {
+				return fn(ctx, req, rsp)
+			}
+			if imd, iok := metadata.FromIncomingContext(ctx); iok && imd != nil {
+				omd, ook := metadata.FromOutgoingContext(ctx)
+				if !ook || omd == nil {
+					omd = metadata.New(len(imd))
+				}
+				ctx = metadata.NewOutgoingContext(ctx, metadata.Merge(omd, metadata.Copy(imd, exclude...), false))
+			}
+			return fn(ctx, req, rsp)
+		}
+	}
+}