Let's start caching some of the backlog data on the server

socketserver/internal/server/backend.go

@@ -74,14 +74,16 @@ func HBackendPublishRequest(w http.ResponseWriter, r *http.Request) {
 
 	cmd := formData.Get("cmd")
 	json := formData.Get("args")
-	chat := formData.Get("chat")
-	watchChannel := formData.Get("channel")
+	channel := formData.Get("channel")
+	scope := formData.Get("scope")
 	cm := ClientMessage{MessageID: -1, Command: Command(cmd), origArguments: json}
 	var count int
-	if chat != "" {
-		count = PublishToChat(chat, cm)
-	} else if watchChannel != "" {
-		count = PublishToWatchers(watchChannel, cm)
+	if scope == "chat" {
+		count = PublishToChat(channel, cm)
+	} else if scope == "channel" {
+		count = PublishToWatchers(channel, cm)
+	} else if scope == "global" {
+		count = PublishToAll(cm)
 	} else {
 		w.WriteHeader(400)
 		fmt.Fprint(w, "Need to specify either chat or channel")

socketserver/internal/server/backlog.go

@@ -1 +1,89 @@
 package server
+
+import (
+	"errors"
+	"fmt"
+	"net/http"
+)
+
+// this value is just docs right now
+var ServerInitiatedCommands = []string{
+	/// Global updates & notices
+	"update_news", // timecache:global
+	"message",     // timecache:global
+	"reload_ff",   // timecache:global
+
+	/// Emote updates
+	"reload_badges", // timecache:global
+	"set_badge",     // timecache:multichat
+	"reload_set",    // timecache:multichat
+	"load_set",      // TODO what are the semantics of this?
+
+	/// User auth
+	"do_authorize", // nocache:single
+
+	/// Channel data
+	// extra emote sets included in the chat
+	"follow_sets", // mustcache:chat
+	// extra follow buttons below the stream
+	"follow_buttons", // mustcache:watching
+	// SRL race data
+	"srl_race", // cachelast:watching
+
+	/// Chatter/viewer counts
+	"chatters", // cachelast:watching
+	"viewers",  // cachelast:watching
+}
+var _ = ServerInitiatedCommands
+
+type BacklogCacheType int
+
+const (
+	// This is not a cache type.
+	CacheTypeInvalid BacklogCacheType = iota
+	// This message cannot be cached.
+	CacheTypeNever
+	// Save the last 24 hours of this message.
+	// If a client indicates that it has reconnected, replay the messages sent after the disconnect.
+	CacheTypeTimestamps
+	// Save only the last copy of this message, and always send it when the backlog is requested.
+	CacheTypeLastOnly
+	// Save this backlog data to disk with its timestamp.
+	// Send it when the backlog is requested, or after a reconnect if it was updated.
+	CacheTypePersistent
+)
+
+type MessageTargetType int
+
+const (
+	// This is not a message target.
+	MsgTargetTypeInvalid MessageTargetType = iota
+	// This message is targeted to a single TODO(user or connection)
+	MsgTargetTypeSingle
+	// This message is targeted to all users in a chat
+	MsgTargetTypeChat
+	// This message is targeted to all users in multiple chats
+	MsgTargetTypeMultichat
+	// This message is targeted to all users watching a stream
+	MsgTargetTypeWatching
+	// This message is sent to all FFZ users.
+	MsgTargetTypeGlobal
+)
+
+// Returned by BacklogCacheType.UnmarshalJSON()
+var ErrorUnrecognizedCacheType = errors.New("Invalid value for cachetype")
+
+// Returned by MessageTargetType.UnmarshalJSON()
+var ErrorUnrecognizedTargetType = errors.New("Invalid value for message target")
+
+// note: see types.go for methods on these
+
+func HBackendSaveBacklog(w http.ResponseWriter, r *http.Request) {
+	formData, err := UnsealRequest(r.Form)
+	if err != nil {
+		w.WriteHeader(403)
+		fmt.Fprintf(w, "Error: %v", err)
+		return
+	}
+
+}

socketserver/internal/server/commands.go

@@ -54,6 +54,8 @@ func HandleHello(conn *websocket.Conn, client *ClientInfo, msg ClientMessage) (r
 		client.ClientID = uuid.NewV4()
 	}
 
+	SubscribeGlobal(client)
+
 	return ClientMessage{
 		Arguments: client.ClientID.String(),
 	}, nil

socketserver/internal/server/types.go

@@ -84,5 +84,120 @@ type ClientInfo struct {
 
 	// Server-initiated messages should be sent here
 	// Never nil.
-	MessageChannel   chan <- ClientMessage
+	MessageChannel chan<- ClientMessage
+}
+
+func (bct BacklogCacheType) Name() string {
+	switch bct {
+	case CacheTypeInvalid:
+		return ""
+	case CacheTypeNever:
+		return "never"
+	case CacheTypeTimestamps:
+		return "timed"
+	case CacheTypeLastOnly:
+		return "last"
+	case CacheTypePersistent:
+		return "persist"
+	}
+	panic("Invalid BacklogCacheType value")
+}
+
+var CacheTypesByName = map[string]BacklogCacheType{
+	"never":   CacheTypeNever,
+	"timed":   CacheTypeTimestamps,
+	"last":    CacheTypeLastOnly,
+	"persist": CacheTypePersistent,
+}
+
+func BacklogCacheTypeByName(name string) (bct BacklogCacheType) {
+	// CacheTypeInvalid is the zero value so it doesn't matter
+	bct, _ = CacheTypesByName[name]
+	return
+}
+
+// Implements Stringer
+func (bct BacklogCacheType) String() string { return bct.Name() }
+
+// Implements json.Marshaler
+func (bct BacklogCacheType) MarshalJSON() ([]byte, error) {
+	return json.Marshal(bct.Name())
+}
+
+// Implements json.Unmarshaler
+func (pbct *BacklogCacheType) UnmarshalJSON(data []byte) error {
+	var str string
+	err := json.Unmarshal(data, &str)
+	if err != nil {
+		return err
+	}
+	if str == "" {
+		*pbct = CacheTypeInvalid
+		return nil
+	}
+	val := BacklogCacheTypeByName(str)
+	if val != CacheTypeInvalid {
+		*pbct = val
+		return nil
+	}
+	return ErrorUnrecognizedCacheType
+}
+
+func (mtt MessageTargetType) Name() string {
+	switch mtt {
+	case MsgTargetTypeInvalid:
+		return ""
+	case MsgTargetTypeSingle:
+		return "single"
+	case MsgTargetTypeChat:
+		return "chat"
+	case MsgTargetTypeMultichat:
+		return "multichat"
+	case MsgTargetTypeWatching:
+		return "channel"
+	case MsgTargetTypeGlobal:
+		return "global"
+	}
+	panic("Invalid MessageTargetType value")
+}
+
+var TargetTypesByName = map[string]MessageTargetType{
+	"single":    MsgTargetTypeSingle,
+	"chat":      MsgTargetTypeChat,
+	"multichat": MsgTargetTypeMultichat,
+	"channel":   MsgTargetTypeWatching,
+	"global":    MsgTargetTypeGlobal,
+}
+
+func MessageTargetTypeByName(name string) (mtt MessageTargetType) {
+	// MsgTargetTypeInvalid is the zero value so it doesn't matter
+	mtt, _ = TargetTypesByName[name]
+	return
+}
+
+// Implements Stringer
+func (mtt MessageTargetType) String() string { return mtt.Name() }
+
+// Implements json.Marshaler
+func (mtt MessageTargetType) MarshalJSON() ([]byte, error) {
+	return json.Marshal(mtt.Name())
+}
+
+// Implements json.Unmarshaler
+func (pmtt *MessageTargetType) UnmarshalJSON(data []byte) error {
+	var str string
+	err := json.Unmarshal(data, &str)
+	if err != nil {
+		return err
+	}
+	if str == "" {
+		*pmtt = MsgTargetTypeInvalid
+		return nil
+	}
+	mtt := MessageTargetTypeByName(str)
+	if mtt != MsgTargetTypeInvalid {
+		*pmtt = mtt
+		return nil
+	}
+	return ErrorUnrecognizedTargetType
 }