Simplify tlsync types (#3139)

Replace enums with (const) object types. Was supposed to include
https://github.com/tldraw/tldraw/pull/3144, but had to bail out

### Change Type

<!-- ❗ Please select a 'Scope' label ❗️ -->

- [ ] `sdk` — Changes the tldraw SDK
- [ ] `dotcom` — Changes the tldraw.com web app
- [ ] `docs` — Changes to the documentation, examples, or templates.
- [ ] `vs code` — Changes to the vscode plugin
- [x] `internal` — Does not affect user-facing stuff

<!-- ❗ Please select a 'Type' label ❗️ -->

- [ ] `bugfix` — Bug fix
- [ ] `feature` — New feature
- [ ] `improvement` — Improving existing features
- [ ] `chore` — Updating dependencies, other boring stuff
- [ ] `galaxy brain` — Architectural changes
- [ ] `tests` — Changes to any test code
- [ ] `tools` — Changes to infrastructure, CI, internal scripts,
debugging tools, etc.
- [x] `dunno` — I don't know

packages/tlsync/src/lib/RoomSession.ts

@@ -2,11 +2,13 @@ import { SerializedSchema, UnknownRecord } from '@tldraw/store'
 import { TLRoomSocket } from './TLSyncRoom'
 import { TLSocketServerSentDataEvent } from './protocol'
 
-export enum RoomSessionState {
+export const RoomSessionState = {
-	AWAITING_CONNECT_MESSAGE = 'awaiting-connect-message',
+	AwaitingConnectMessage: 'awaiting-connect-message',
-	AWAITING_REMOVAL = 'awaiting-removal',
+	AwaitingRemoval: 'awaiting-removal',
-	CONNECTED = 'connected',
+	Connected: 'connected',
-}
+} as const
+
+export type RoomSessionState = (typeof RoomSessionState)[keyof typeof RoomSessionState]
 
 export const SESSION_START_WAIT_TIME = 10000
 export const SESSION_REMOVAL_WAIT_TIME = 10000
@@ -14,21 +16,21 @@ export const SESSION_IDLE_TIMEOUT = 20000
 
 export type RoomSession<R extends UnknownRecord> =
 	| {
-			state: RoomSessionState.AWAITING_CONNECT_MESSAGE
+			state: typeof RoomSessionState.AwaitingConnectMessage
 			sessionKey: string
 			presenceId: string
 			socket: TLRoomSocket<R>
 			sessionStartTime: number
 	  }
 	| {
-			state: RoomSessionState.AWAITING_REMOVAL
+			state: typeof RoomSessionState.AwaitingRemoval
 			sessionKey: string
 			presenceId: string
 			socket: TLRoomSocket<R>
 			cancellationTime: number
 	  }
 	| {
-			state: RoomSessionState.CONNECTED
+			state: typeof RoomSessionState.Connected
 			sessionKey: string
 			presenceId: string
 			socket: TLRoomSocket<R>

packages/tlsync/src/lib/TLSyncRoom.ts

@@ -140,14 +140,14 @@ export class TLSyncRoom<R extends UnknownRecord> {
 	pruneSessions = () => {
 		for (const client of this.sessions.values()) {
 			switch (client.state) {
-				case RoomSessionState.CONNECTED: {
+				case RoomSessionState.Connected: {
 					const hasTimedOut = timeSince(client.lastInteractionTime) > SESSION_IDLE_TIMEOUT
 					if (hasTimedOut || !client.socket.isOpen) {
 						this.cancelSession(client.sessionKey)
 					}
 					break
 				}
-				case RoomSessionState.AWAITING_CONNECT_MESSAGE: {
+				case RoomSessionState.AwaitingConnectMessage: {
 					const hasTimedOut = timeSince(client.sessionStartTime) > SESSION_START_WAIT_TIME
 					if (hasTimedOut || !client.socket.isOpen) {
 						// remove immediately
@@ -155,7 +155,7 @@ export class TLSyncRoom<R extends UnknownRecord> {
 					}
 					break
 				}
-				case RoomSessionState.AWAITING_REMOVAL: {
+				case RoomSessionState.AwaitingRemoval: {
 					const hasTimedOut = timeSince(client.cancellationTime) > SESSION_REMOVAL_WAIT_TIME
 					if (hasTimedOut) {
 						this.removeSession(client.sessionKey)
@@ -397,7 +397,7 @@ export class TLSyncRoom<R extends UnknownRecord> {
 			console.warn('Tried to send message to unknown session', message.type)
 			return
 		}
-		if (session.state !== RoomSessionState.CONNECTED) {
+		if (session.state !== RoomSessionState.Connected) {
 			console.warn('Tried to send message to disconnected client', message.type)
 			return
 		}
@@ -433,7 +433,7 @@ export class TLSyncRoom<R extends UnknownRecord> {
 	_flushDataMessages(sessionKey: string) {
 		const session = this.sessions.get(sessionKey)
 
-		if (!session || session.state !== RoomSessionState.CONNECTED) {
+		if (!session || session.state !== RoomSessionState.Connected) {
 			return
 		}
 
@@ -489,13 +489,13 @@ export class TLSyncRoom<R extends UnknownRecord> {
 			return
 		}
 
-		if (session.state === RoomSessionState.AWAITING_REMOVAL) {
+		if (session.state === RoomSessionState.AwaitingRemoval) {
 			console.warn('Tried to cancel session that is already awaiting removal')
 			return
 		}
 
 		this.sessions.set(sessionKey, {
-			state: RoomSessionState.AWAITING_REMOVAL,
+			state: RoomSessionState.AwaitingRemoval,
 			sessionKey,
 			presenceId: session.presenceId,
 			socket: session.socket,
@@ -517,7 +517,7 @@ export class TLSyncRoom<R extends UnknownRecord> {
 		sourceSessionKey: string
 	}) {
 		this.sessions.forEach((session) => {
-			if (session.state !== RoomSessionState.CONNECTED) return
+			if (session.state !== RoomSessionState.Connected) return
 			if (sourceSessionKey === session.sessionKey) return
 			if (!session.socket.isOpen) {
 				this.cancelSession(session.sessionKey)
@@ -556,7 +556,7 @@ export class TLSyncRoom<R extends UnknownRecord> {
 	handleNewSession = (sessionKey: string, socket: TLRoomSocket<R>) => {
 		const existing = this.sessions.get(sessionKey)
 		this.sessions.set(sessionKey, {
-			state: RoomSessionState.AWAITING_CONNECT_MESSAGE,
+			state: RoomSessionState.AwaitingConnectMessage,
 			sessionKey,
 			socket,
 			presenceId: existing?.presenceId ?? this.presenceType.createId(),
@@ -628,7 +628,7 @@ export class TLSyncRoom<R extends UnknownRecord> {
 				return this.handlePushRequest(session, message)
 			}
 			case 'ping': {
-				if (session.state === RoomSessionState.CONNECTED) {
+				if (session.state === RoomSessionState.Connected) {
 					session.lastInteractionTime = Date.now()
 				}
 				return this.sendMessage(session.sessionKey, { type: 'pong' })
@@ -685,7 +685,7 @@ export class TLSyncRoom<R extends UnknownRecord> {
 
 		const connect = (msg: TLSocketServerSentEvent<R>) => {
 			this.sessions.set(session.sessionKey, {
-				state: RoomSessionState.CONNECTED,
+				state: RoomSessionState.Connected,
 				sessionKey: session.sessionKey,
 				presenceId: session.presenceId,
 				socket: session.socket,
@@ -786,7 +786,7 @@ export class TLSyncRoom<R extends UnknownRecord> {
 		message: Extract<TLSocketClientSentEvent<R>, { type: 'push' }>
 	) {
 		// We must be connected to handle push requests
-		if (session.state !== RoomSessionState.CONNECTED) {
+		if (session.state !== RoomSessionState.Connected) {
 			return
 		}
 

packages/tlsync/src/lib/diff.ts

@@ -3,17 +3,20 @@ import { objectMapEntries, objectMapValues } from '@tldraw/utils'
 import isEqual from 'lodash.isequal'
 
 /** @public */
-export enum RecordOpType {
+export const RecordOpType = {
-	Put = 'put',
+	Put: 'put',
-	Patch = 'patch',
+	Patch: 'patch',
-	Remove = 'remove',
+	Remove: 'remove',
-}
+} as const
+
+/** @public */
+export type RecordOpType = (typeof RecordOpType)[keyof typeof RecordOpType]
 
 /** @public */
 export type RecordOp<R extends UnknownRecord> =
-	| [RecordOpType.Put, R]
+	| [typeof RecordOpType.Put, R]
-	| [RecordOpType.Patch, ObjectDiff]
+	| [typeof RecordOpType.Patch, ObjectDiff]
-	| [RecordOpType.Remove]
+	| [typeof RecordOpType.Remove]
 
 /**
  * A one-way (non-reversible) diff designed for small json footprint. These are mainly intended to
@@ -60,20 +63,22 @@ export const getNetworkDiff = <R extends UnknownRecord>(
 }
 
 /** @public */
-export enum ValueOpType {
+export const ValueOpType = {
-	Put = 'put',
+	Put: 'put',
-	Delete = 'delete',
+	Delete: 'delete',
-	Append = 'append',
+	Append: 'append',
-	Patch = 'patch',
+	Patch: 'patch',
-}
+} as const
+export type ValueOpType = (typeof ValueOpType)[keyof typeof ValueOpType]
+
 /** @public */
-export type PutOp = [type: ValueOpType.Put, value: unknown]
+export type PutOp = [type: typeof ValueOpType.Put, value: unknown]
 /** @public */
-export type AppendOp = [type: ValueOpType.Append, values: unknown[], offset: number]
+export type AppendOp = [type: typeof ValueOpType.Append, values: unknown[], offset: number]
 /** @public */
-export type PatchOp = [type: ValueOpType.Patch, diff: ObjectDiff]
+export type PatchOp = [type: typeof ValueOpType.Patch, diff: ObjectDiff]
 /** @public */
-export type DeleteOp = [type: ValueOpType.Delete]
+export type DeleteOp = [type: typeof ValueOpType.Delete]
 
 /** @public */
 export type ValueOp = PutOp | AppendOp | PatchOp | DeleteOp

packages/tlsync/src/lib/protocol.ts

@@ -5,12 +5,16 @@ import { NetworkDiff, ObjectDiff, RecordOpType } from './diff'
 export const TLSYNC_PROTOCOL_VERSION = 5
 
 /** @public */
-export enum TLIncompatibilityReason {
+export const TLIncompatibilityReason = {
-	ClientTooOld = 'clientTooOld',
+	ClientTooOld: 'clientTooOld',
-	ServerTooOld = 'serverTooOld',
+	ServerTooOld: 'serverTooOld',
-	InvalidRecord = 'invalidRecord',
+	InvalidRecord: 'invalidRecord',
-	InvalidOperation = 'invalidOperation',
+	InvalidOperation: 'invalidOperation',
-}
+} as const
+
+/** @public */
+export type TLIncompatibilityReason =
+	(typeof TLIncompatibilityReason)[keyof typeof TLIncompatibilityReason]
 
 /** @public */
 export type TLSocketServerSentEvent<R extends UnknownRecord> =
@@ -55,7 +59,7 @@ export type TLPushRequest<R extends UnknownRecord> =
 	| {
 			type: 'push'
 			clientClock: number
-			presence: [RecordOpType.Patch, ObjectDiff] | [RecordOpType.Put, R]
+			presence: [typeof RecordOpType.Patch, ObjectDiff] | [typeof RecordOpType.Put, R]
 	  }
 	| {
 			type: 'push'

packages/tlsync/src/test/TLServer.test.ts

@@ -109,7 +109,7 @@ describe('TLServer', () => {
 		expect(server.roomState?.persistenceKey).toBe('test-persistence-key')
 		expect(server.roomState?.room.sessions.size).toBe(1)
 		expect(server.roomState?.room.sessions.get('test-session-key')?.state).toBe(
-			RoomSessionState.AWAITING_CONNECT_MESSAGE
+			RoomSessionState.AwaitingConnectMessage
 		)
 	})
 
@@ -135,7 +135,7 @@ describe('TLServer', () => {
 		sockets.client.on('message', onClientMessage)
 
 		expect(server.roomState?.room.sessions.get('test-session-key')?.state).toBe(
-			RoomSessionState.AWAITING_CONNECT_MESSAGE
+			RoomSessionState.AwaitingConnectMessage
 		)
 
 		for (const chunk of chunks) {
@@ -145,7 +145,7 @@ describe('TLServer', () => {
 		await receivedPromise
 
 		expect(server.roomState?.room.sessions.get('test-session-key')?.state).toBe(
-			RoomSessionState.CONNECTED
+			RoomSessionState.Connected
 		)
 
 		expect(onClientMessage).toHaveBeenCalledTimes(1)