From 2ec5934d2e8fafd6f48975e4abb843a7e06cb141 Mon Sep 17 00:00:00 2001
From: Denis Arh <denis.arh@kendu.si>
Date: Wed, 24 Oct 2018 17:17:31 +0200
Subject: [PATCH] User/channel activity echoing service

---
 internal/payload/incoming/channel.go      |  6 ++++++
 internal/payload/incoming/payload.go      |  2 ++
 internal/payload/outgoing/channel.go      | 11 +++++++++++
 internal/payload/outgoing/payload.go      |  2 ++
 sam/websocket/session_incoming.go         |  2 ++
 sam/websocket/session_incoming_channel.go |  9 +++++++++
 6 files changed, 32 insertions(+)

diff --git a/internal/payload/incoming/channel.go b/internal/payload/incoming/channel.go
index a01bdce7d..ab0003970 100644
--- a/internal/payload/incoming/channel.go
+++ b/internal/payload/incoming/channel.go
@@ -32,4 +32,10 @@ type (
 	ChannelDelete struct {
 		ChannelID string `json:"id"`
 	}
+
+	// ChannelActivity is sent from the client when there is an activity on the channel...
+	ChannelActivity struct {
+		ChannelID uint64 `json:"ID,string"`
+		Kind      string `json:"kind,omitempty"`
+	}
 )
diff --git a/internal/payload/incoming/payload.go b/internal/payload/incoming/payload.go
index 48289c9bb..1a4f2a5a9 100644
--- a/internal/payload/incoming/payload.go
+++ b/internal/payload/incoming/payload.go
@@ -12,6 +12,8 @@ type Payload struct {
 
 	*ChannelViewRecord `json:"recordChannelView"`
 
+	*ChannelActivity `json:"channelActivity"`
+
 	// Get channel message history
 	*Messages `json:"messages"`
 
diff --git a/internal/payload/outgoing/channel.go b/internal/payload/outgoing/channel.go
index 692711f95..c25a78a5f 100644
--- a/internal/payload/outgoing/channel.go
+++ b/internal/payload/outgoing/channel.go
@@ -22,6 +22,13 @@ type (
 		UserID string `json:"userID"`
 	}
 
+	// ChannelActivity indicates where the activity is and who is active
+	ChannelActivity struct {
+		ID     uint64 `json:"channelID,string"`
+		UserID uint64 `json:"userID,string"`
+		Kind   string `json:"kind,omitempty"`
+	}
+
 	Channel struct {
 		// Channel to part (nil) for ALL channels
 		ID            string       `json:"ID"`
@@ -49,6 +56,10 @@ func (p *ChannelPart) EncodeMessage() ([]byte, error) {
 	return json.Marshal(Payload{ChannelPart: p})
 }
 
+func (p *ChannelActivity) EncodeMessage() ([]byte, error) {
+	return json.Marshal(Payload{ChannelActivity: p})
+}
+
 func (p *Channel) EncodeMessage() ([]byte, error) {
 	return json.Marshal(Payload{Channel: p})
 }
diff --git a/internal/payload/outgoing/payload.go b/internal/payload/outgoing/payload.go
index 422b95008..92da9df72 100644
--- a/internal/payload/outgoing/payload.go
+++ b/internal/payload/outgoing/payload.go
@@ -15,6 +15,8 @@ type (
 		*Channel     `json:"channel,omitempty"`
 		*ChannelSet  `json:"channels,omitempty"`
 
+		*ChannelActivity `json:"channelActivity,omitempty"`
+
 		*ChannelMember    `json:"channelMember,omitempty"`
 		*ChannelMemberSet `json:"channelMembers,omitempty"`
 
diff --git a/sam/websocket/session_incoming.go b/sam/websocket/session_incoming.go
index 52623ad2c..613e7788f 100644
--- a/sam/websocket/session_incoming.go
+++ b/sam/websocket/session_incoming.go
@@ -39,6 +39,8 @@ func (s *Session) dispatch(raw []byte) error {
 		return s.channelUpdate(ctx, p.ChannelUpdate)
 	case p.ChannelViewRecord != nil:
 		return s.channelViewRecord(ctx, p.ChannelViewRecord)
+	case p.ChannelActivity != nil:
+		return s.channelActivity(ctx, p.ChannelActivity)
 
 	case p.Users != nil:
 		return s.userList(ctx, p.Users)
diff --git a/sam/websocket/session_incoming_channel.go b/sam/websocket/session_incoming_channel.go
index ef7dabbf6..74cb266fb 100644
--- a/sam/websocket/session_incoming_channel.go
+++ b/sam/websocket/session_incoming_channel.go
@@ -119,3 +119,12 @@ func (s *Session) channelViewRecord(ctx context.Context, p *incoming.ChannelView
 
 	return s.svc.ch.With(ctx).RecordView(channelID, userID, lastMessageID)
 }
+
+// Echoes received channel activity back to all subscribers
+func (s *Session) channelActivity(ctx context.Context, p *incoming.ChannelActivity) error {
+	return s.sendToAllSubscribers(&outgoing.ChannelActivity{
+		ID:     p.ChannelID,
+		UserID: auth.GetIdentityFromContext(ctx).Identity(),
+		Kind:   p.Kind,
+	}, payload.Uint64toa(p.ChannelID))
+}