From e143e2b547ce7c306e05ce22077ac1ff41a97102 Mon Sep 17 00:00:00 2001
From: Vasiliy Tolstov <v.tolstov@unistack.org>
Date: Thu, 16 Dec 2021 15:03:42 +0300
Subject: [PATCH] client: allow to set metadata for message

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>
---
 client/client.go  |  1 +
 client/lookup.go  |  2 +-
 client/noop.go    |  4 ++++
 client/options.go | 15 ++++++++++++++-
 client/retry.go   |  2 +-
 5 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/client/client.go b/client/client.go
index 087f263f..36bbb6db 100644
--- a/client/client.go
+++ b/client/client.go
@@ -49,6 +49,7 @@ type Message interface {
 	Topic() string
 	Payload() interface{}
 	ContentType() string
+	Metadata() metadata.Metadata
 }
 
 // Request is the interface for a synchronous request used by Call or Stream
diff --git a/client/lookup.go b/client/lookup.go
index e2677f90..5c409ba1 100644
--- a/client/lookup.go
+++ b/client/lookup.go
@@ -12,7 +12,7 @@ import (
 type LookupFunc func(context.Context, Request, CallOptions) ([]string, error)
 
 // LookupRoute for a request using the router and then choose one using the selector
-func LookupRoute(ctx context.Context, req Request, opts CallOptions) ([]string, error) {
+func LookupRoute(_ context.Context, req Request, opts CallOptions) ([]string, error) {
 	// check to see if an address was provided as a call option
 	if len(opts.Address) > 0 {
 		return opts.Address, nil
diff --git a/client/noop.go b/client/noop.go
index 809fa3fa..e654388e 100644
--- a/client/noop.go
+++ b/client/noop.go
@@ -139,6 +139,10 @@ func (n *noopMessage) ContentType() string {
 	return n.opts.ContentType
 }
 
+func (n *noopMessage) Metadata() metadata.Metadata {
+	return n.opts.Metadata
+}
+
 func (n *noopClient) newCodec(contentType string) (codec.Codec, error) {
 	if cf, ok := n.opts.Codecs[contentType]; ok {
 		return cf, nil
diff --git a/client/options.go b/client/options.go
index 9a2eb73d..c7abd912 100644
--- a/client/options.go
+++ b/client/options.go
@@ -8,6 +8,7 @@ import (
 	"go.unistack.org/micro/v3/broker"
 	"go.unistack.org/micro/v3/codec"
 	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/metadata"
 	"go.unistack.org/micro/v3/meter"
 	"go.unistack.org/micro/v3/network/transport"
 	"go.unistack.org/micro/v3/register"
@@ -128,7 +129,7 @@ type PublishOptions struct {
 
 // NewMessageOptions creates message options struct
 func NewMessageOptions(opts ...MessageOption) MessageOptions {
-	options := MessageOptions{}
+	options := MessageOptions{Metadata: metadata.New(1)}
 	for _, o := range opts {
 		o(&options)
 	}
@@ -137,7 +138,10 @@ func NewMessageOptions(opts ...MessageOption) MessageOptions {
 
 // MessageOptions holds client message options
 type MessageOptions struct {
+	// Metadata additional metadata
+	Metadata metadata.Metadata
 	// ContentType specify content-type of message
+	// deprecated
 	ContentType string
 }
 
@@ -517,6 +521,7 @@ func WithSelectOptions(sops ...selector.SelectOption) CallOption {
 // Deprecated
 func WithMessageContentType(ct string) MessageOption {
 	return func(o *MessageOptions) {
+		o.Metadata.Set(metadata.HeaderContentType, ct)
 		o.ContentType = ct
 	}
 }
@@ -524,10 +529,18 @@ func WithMessageContentType(ct string) MessageOption {
 // MessageContentType sets the message content type
 func MessageContentType(ct string) MessageOption {
 	return func(o *MessageOptions) {
+		o.Metadata.Set(metadata.HeaderContentType, ct)
 		o.ContentType = ct
 	}
 }
 
+// MessageMetadata sets the message metadata
+func MessageMetadata(k, v string) MessageOption {
+	return func(o *MessageOptions) {
+		o.Metadata.Set(k, v)
+	}
+}
+
 // StreamingRequest specifies that request is streaming
 func StreamingRequest(b bool) RequestOption {
 	return func(o *RequestOptions) {
diff --git a/client/retry.go b/client/retry.go
index 89d22aef..40272fd2 100644
--- a/client/retry.go
+++ b/client/retry.go
@@ -20,7 +20,7 @@ func RetryNever(ctx context.Context, req Request, retryCount int, err error) (bo
 }
 
 // RetryOnError retries a request on a 500 or timeout error
-func RetryOnError(ctx context.Context, req Request, retryCount int, err error) (bool, error) {
+func RetryOnError(_ context.Context, _ Request, _ int, err error) (bool, error) {
 	if err == nil {
 		return false, nil
 	}