initial implementation of draft/persistence

gencapdefs.py

@@ -189,6 +189,12 @@
         url="https://github.com/ircv3/ircv3-specifications/pull/489",
         standard="draft IRCv3",
     ),
+    CapDef(
+        identifier="Persistence",
+        name="draft/persistence",
+        url="https://github.com/ircv3/ircv3-specifications/pull/503",
+        standard="proposed IRCv3",
+    ),
 ]
 
 def validate_defs():

irc/caps/defs.go

@@ -7,7 +7,7 @@ package caps
 
 const (
 	// number of recognized capabilities:
-	numCapabs = 29
+	numCapabs = 30
 	// length of the uint64 array that represents the bitset:
 	bitsetLen = 1
 )
@@ -61,6 +61,10 @@ const (
 	// https://github.com/ircv3/ircv3-specifications/pull/398
 	Multiline Capability = iota
 
+	// Persistence is the proposed IRCv3 capability named "draft/persistence":
+	// https://github.com/ircv3/ircv3-specifications/pull/503
+	Persistence Capability = iota
+
 	// ReadMarker is the draft IRCv3 capability named "draft/read-marker":
 	// https://github.com/ircv3/ircv3-specifications/pull/489
 	ReadMarker Capability = iota
@@ -145,6 +149,7 @@ var (
 		"draft/event-playback",
 		"draft/languages",
 		"draft/multiline",
+		"draft/persistence",
 		"draft/read-marker",
 		"draft/relaymsg",
 		"echo-message",

irc/commands.go

@@ -233,6 +233,10 @@ func init() {
 			usablePreReg: true,
 			minParams:    1,
 		},
+		"PERSISTENCE": {
+			handler:   persistenceHandler,
+			minParams: 1,
+		},
 		"PING": {
 			handler:      pingHandler,
 			usablePreReg: true,

irc/handlers.go

@@ -2599,6 +2599,91 @@ func passHandler(server *Server, client *Client, msg ircmsg.Message, rb *Respons
 	return false
 }
 
+// PERSISTENCE <subcommand> [params...]
+func persistenceHandler(server *Server, client *Client, msg ircmsg.Message, rb *ResponseBuffer) bool {
+	account := client.Account()
+	if account == "" {
+		rb.Add(nil, server.name, "FAIL", "PERSISTENCE", "ACCOUNT_REQUIRED", client.t("You're not logged into an account"))
+		return false
+	}
+
+	switch strings.ToUpper(msg.Params[0]) {
+	case "GET":
+		reportPersistenceStatus(client, rb, false)
+	case "SET":
+		if len(msg.Params) == 1 {
+			goto fail
+		}
+		var desiredSetting PersistentStatus
+		switch strings.ToUpper(msg.Params[1]) {
+		case "DEFAULT":
+			desiredSetting = PersistentUnspecified
+		case "OFF":
+			desiredSetting = PersistentDisabled
+		case "ON":
+			desiredSetting = PersistentMandatory
+		default:
+			goto fail
+		}
+
+		broadcast := false
+		_, err := server.accounts.ModifyAccountSettings(account,
+			func(input AccountSettings) (output AccountSettings, err error) {
+				output = input
+				output.AlwaysOn = desiredSetting
+				broadcast = output.AlwaysOn != input.AlwaysOn
+				return
+			})
+		if err != nil {
+			server.logger.Error("internal", "couldn't modify persistence setting", err.Error())
+			rb.Add(nil, server.name, "FAIL", "PERSISTENCE", "UNKNOWN_ERROR", client.t("An error occurred"))
+			return false
+		}
+
+		reportPersistenceStatus(client, rb, broadcast)
+
+	default:
+		goto fail
+	}
+
+	return false
+
+fail:
+	rb.Add(nil, server.name, "FAIL", "PERSISTENCE", "INVALID_PARAMS", client.t("Invalid parameters"))
+	return false
+}
+
+func reportPersistenceStatus(client *Client, rb *ResponseBuffer, broadcast bool) {
+	settings := client.AccountSettings()
+	serverSetting := client.server.Config().Accounts.Multiclient.AlwaysOn
+	effectiveSetting := persistenceEnabled(serverSetting, settings.AlwaysOn)
+	toString := func(setting PersistentStatus) string {
+		switch setting {
+		case PersistentUnspecified:
+			return "DEFAULT"
+		case PersistentDisabled:
+			return "OFF"
+		case PersistentMandatory:
+			return "ON"
+		default:
+			return "*" // impossible
+		}
+	}
+	storedSettingStr := toString(settings.AlwaysOn)
+	effectiveSettingStr := "OFF"
+	if effectiveSetting {
+		effectiveSettingStr = "ON"
+	}
+	rb.Add(nil, client.server.name, "PERSISTENCE", "STATUS", storedSettingStr, effectiveSettingStr)
+	if broadcast {
+		for _, session := range client.Sessions() {
+			if session != rb.session && session.capabilities.Has(caps.Persistence) {
+				session.Send(nil, client.server.name, "PERSISTENCE", "STATUS", storedSettingStr, effectiveSettingStr)
+			}
+		}
+	}
+}
+
 // PING [params...]
 func pingHandler(server *Server, client *Client, msg ircmsg.Message, rb *ResponseBuffer) bool {
 	rb.Add(nil, server.name, "PONG", server.name, msg.Params[0])

irc/help.go

@@ -413,6 +413,13 @@ Leaves the given channels and shows people the given reason.`,
 
 When the server requires a connection password to join, used to send us the
 password.`,
+	},
+	"persistence": {
+		text: `PERSISTENCE [params]
+
+PERSISTENCE is a command associated with an IRC protocol extension for
+persistent connections. End users should probably use /NS GET ALWAYS-ON
+and /NS SET ALWAYS-ON instead.`,
 	},
 	"ping": {
 		text: `PING <args>...

irc/server.go

@@ -420,6 +420,9 @@ func (server *Server) playRegistrationBurst(session *Session) {
 
 	rb := NewResponseBuffer(session)
 	server.RplISupport(c, rb)
+	if d.account != "" && session.capabilities.Has(caps.Persistence) {
+		reportPersistenceStatus(c, rb, false)
+	}
 	server.Lusers(c, rb)
 	server.MOTD(c, rb)
 	rb.Send(true)