Add initial working prototype

.dockerignore

@@ -0,0 +1,9 @@
+node_modules/
+dist/
+
+/packages/ketchup-client/
+/packages/ketchup-react/
+/packages/space-client/
+
+.eslintcache
+*.log

.gitignore

@@ -0,0 +1,5 @@
+node_modules/
+dist/
+
+.eslintcache
+*.log

Dockerfile

@@ -0,0 +1,20 @@
+FROM node:16-alpine
+
+RUN apk add --no-cache tini
+
+RUN yarn global add lerna
+
+WORKDIR /opt/space-server
+COPY packages/ketchup-common/package.json packages/ketchup-common/
+COPY packages/ketchup-server/package.json packages/ketchup-server/
+COPY packages/space-common/package.json packages/space-common/
+COPY packages/space-server/package.json packages/space-server/
+COPY package.json yarn.lock lerna.json ./
+RUN lerna bootstrap
+
+COPY . ./
+RUN lerna run build
+
+ENTRYPOINT ["tini", "--"]
+CMD ["node", "packages/space-server"]
+EXPOSE 80

docker-compose.yaml

@@ -0,0 +1,6 @@
+version: "3.8"
+services:
+  server:
+    build: .
+    ports:
+      - "4000:80"

lerna.json

@@ -0,0 +1,8 @@
+{
+  "packages": [
+    "packages/*"
+  ],
+  "version": "independent",
+  "npmClient": "yarn",
+  "useWorkspaces": true
+}

package.json

@@ -0,0 +1,15 @@
+{
+  "name": "space",
+  "version": "0.0.2",
+  "private": true,
+  "workspaces": [
+    "packages/*"
+  ],
+  "scripts": {},
+  "devDependencies": {
+    "lerna": "^4.0.0"
+  },
+  "resolutions": {
+    "acorn": "^8.0.1"
+  }
+}

packages/ketchup-client/.eslintrc.json

@@ -0,0 +1,23 @@
+{
+    "env": {
+        "es2021": true,
+        "browser": true
+    },
+    "extends": [
+        "standard"
+    ],
+    "parser": "@typescript-eslint/parser",
+    "parserOptions": {
+        "ecmaVersion": 12,
+        "sourceType": "module"
+    },
+    "plugins": [
+        "@typescript-eslint"
+    ],
+    "rules": {
+      "comma-dangle": ["error", "only-multiline"],
+      "padded-blocks": "warn",
+      "no-multiple-empty-lines": "warn",
+      "space-before-function-paren": "off"
+    }
+}

packages/ketchup-client/index.ts

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+import { ExponentialBackoff, Websocket, WebsocketBuilder } from 'websocket-ts'
+import { ActionClientMessage, ActionServerMessage, ConfirmServerMessage, HandshakeClientMessage, HandshakeServerMessage, ServerMessage, KetchupSynced } from 'ketchup-common'
+import EventEmitter from 'events'
+
+export default class KetchupClient<State, Action> extends EventEmitter {
+  readonly ws: Websocket
+  synced?: KetchupSynced<State, Action>
+  clientId?: number
+  lastTimestamp?: number
+
+  constructor(
+    url: string,
+    readonly reducer: (state: State, action: Action) => State,
+    private readonly timeSource = Date.now
+  ) {
+    super()
+    console.log('Building KC')
+    this.ws = new WebsocketBuilder(url)
+      .onClose(() => {
+        this.synced = undefined
+        this.clientId = undefined
+        this.lastTimestamp = undefined
+      })
+      .onOpen(ws => {
+        ws.send(JSON.stringify({
+          message: 'handshake',
+          timestamp: timeSource(),
+        } as HandshakeClientMessage))
+      })
+      .onMessage((_, event) => {
+        this.onMessage(JSON.parse(event.data))
+      })
+      .withBackoff(new ExponentialBackoff(100, 7))
+      .build()
+  }
+
+  private onMessage(msg: ServerMessage<State, Action>) {
+    switch (msg.message) {
+      case 'handshake':
+        const hMsg = msg as HandshakeServerMessage<State, Action>
+        this.clientId = hMsg.clientId
+        this.synced = new KetchupSynced(hMsg.confState, hMsg.confBefore, this.reducer, hMsg.unconfActions)
+        this.synced.on('projection', proj => this.emit('projection', proj))
+        this.emit('projection', this.synced.projState)
+        break
+
+      case 'action':
+        this.synced!.tryProcess(msg as ActionServerMessage<Action>)
+        break
+
+      case 'confirm':
+        this.synced!.confirmBefore((msg as ConfirmServerMessage).confBefore)
+        break
+      
+      default:
+        throw new Error(`Unknown message from server: ${msg}`)
+    }
+  }
+
+  dispatch(action: Action, timestamp = this.timeSource()) {
+    // In case of timestamp collision, shift event 1ms into future until timestamp is novel.
+    // TODO: Better handling of events being submitted out of timestamp order
+    if (this.lastTimestamp !== undefined && timestamp <= this.lastTimestamp) {
+      timestamp = this.lastTimestamp + 1
+    }
+
+    if (this.synced?.tryProcess({ timestamp, action, clientId: this.clientId! })) {
+      this.lastTimestamp = timestamp
+      this.ws.send(JSON.stringify({
+        message: 'action',
+        action,
+        timestamp,
+      } as ActionClientMessage<Action>))
+    }
+  }
+}

packages/ketchup-client/package.json

@@ -0,0 +1,26 @@
+{
+  "name": "ketchup-client",
+  "version": "0.1.2",
+  "description": "WebSocket-based rollback state synchronization server.",
+  "main": "dist/index.js",
+  "license": "MIT",
+  "private": true,
+  "dependencies": {
+    "ketchup-common": "^0.1.1",
+    "websocket-ts": "^1.1.0"
+  },
+  "devDependencies": {
+    "@tsconfig/node14": "^1.0.0",
+    "@types/jest": "^26.0.20",
+    "@types/node": "^14.14.22",
+    "@typescript-eslint/eslint-plugin": "^4.14.1",
+    "@typescript-eslint/parser": "^4.14.1",
+    "eslint": "^7.18.0",
+    "jest": "^26.6.3",
+    "ts-jest": "^26.5.0",
+    "typescript": "^4.1.3"
+  },
+  "scripts": {
+    "build": "tsc"
+  }
+}

packages/ketchup-client/tsconfig.json

@@ -0,0 +1,7 @@
+{
+  "extends": "@tsconfig/node14/tsconfig.json",
+  "compilerOptions": {
+    "rootDir": ".",
+    "outDir": "dist"
+  }
+}

packages/ketchup-common/.eslintrc.json

@@ -0,0 +1,24 @@
+{
+    "env": {
+        "es2021": true,
+        "node": true,
+        "browser": true
+    },
+    "extends": [
+        "standard"
+    ],
+    "parser": "@typescript-eslint/parser",
+    "parserOptions": {
+        "ecmaVersion": 12,
+        "sourceType": "module"
+    },
+    "plugins": [
+        "@typescript-eslint"
+    ],
+    "rules": {
+      "comma-dangle": ["error", "only-multiline"],
+      "padded-blocks": "warn",
+      "no-multiple-empty-lines": "warn",
+      "space-before-function-paren": "off"
+    }
+}

packages/ketchup-common/index.spec.ts

@@ -0,0 +1,180 @@
+import { KetchupSynced } from '.'
+
+interface TTTState {
+  board: ('X' | 'O' | undefined)[][]
+}
+const tttInitial = {
+  board: [
+    [undefined, undefined, undefined],
+    [undefined, undefined, undefined],
+    [undefined, undefined, undefined],
+  ],
+}
+interface TTTAction {
+  row: number
+  col: number
+  mark: 'X' | 'O'
+}
+function tttReducer(state: TTTState, { row, col, mark }: TTTAction): TTTState {
+  if (state.board[row][col] !== undefined) {
+    return state
+  }
+  return {
+    board: state.board.map((rArr, rIdx) =>
+      rArr.map((cell, cIdx) => rIdx === row && cIdx === col ? mark : cell)
+    ),
+  }
+}
+
+test('Basic linear', () => {
+  const s = new KetchupSynced(tttInitial, 1000, tttReducer)
+  expect(s.tryProcess({
+    action: { row: 0, col: 0, mark: 'X' },
+    timestamp: 1010,
+    clientId: 0,
+  })).toBe(true)
+  expect(s.tryProcess({
+    action: { row: 1, col: 2, mark: 'O' },
+    timestamp: 1020,
+    clientId: 0,
+  })).toBe(true)
+  expect(s.tryProcess({
+    action: { row: 2, col: 1, mark: 'X' },
+    timestamp: 1030,
+    clientId: 0,
+  })).toBe(true)
+  expect(s.projState).toEqual({
+    board: [
+      ['X', undefined, undefined],
+      [undefined, undefined, 'O'],
+      [undefined, 'X', undefined],
+    ],
+  })
+})
+
+test('Out-of-order', () => {
+  const s = new KetchupSynced(tttInitial, 1000, tttReducer)
+  expect(s.tryProcess({
+    action: { row: 0, col: 0, mark: 'X' },
+    timestamp: 1010,
+    clientId: 0,
+  })).toBe(true)
+  expect(s.tryProcess({
+    action: { row: 1, col: 2, mark: 'X' },
+    timestamp: 1040,
+    clientId: 0,
+  })).toBe(true)
+  expect(s.projState).toEqual({
+    board: [
+      ['X', undefined, undefined],
+      [undefined, undefined, 'X'],
+      [undefined, undefined, undefined],
+    ],
+  })
+  expect(s.tryProcess({
+    action: { row: 1, col: 2, mark: 'O' },
+    timestamp: 1030,
+    clientId: 0,
+  })).toBe(true)
+  expect(s.tryProcess({
+    action: { row: 2, col: 1, mark: 'X' },
+    timestamp: 1020,
+    clientId: 0,
+  })).toBe(true)
+  expect(s.projState).toEqual({
+    board: [
+      ['X', undefined, undefined],
+      [undefined, undefined, 'O'],
+      [undefined, 'X', undefined],
+    ],
+  })
+})
+
+test('Out-of-order with confirms', () => {
+  const s = new KetchupSynced(tttInitial, 1000, tttReducer)
+  expect(s.tryProcess({
+    action: { row: 0, col: 0, mark: 'X' },
+    timestamp: 1010,
+    clientId: 0,
+  })).toBe(true)
+
+  expect(s.confirmBefore(1010)).toBe(0)
+  expect(s.confState).toEqual(tttInitial)
+  expect(s.projs).toEqual([{
+    action: { row: 0, col: 0, mark: 'X' },
+    timestamp: 1010,
+    clientId: 0,
+    state: {
+      board: [
+        ['X', undefined, undefined],
+        [undefined, undefined, undefined],
+        [undefined, undefined, undefined],
+      ],
+    },
+  }])
+
+  expect(s.confirmBefore(1011)).toBe(1)
+  expect(s.confState).toEqual({
+    board: [
+      ['X', undefined, undefined],
+      [undefined, undefined, undefined],
+      [undefined, undefined, undefined],
+    ],
+  })
+  expect(s.projs).toEqual([])
+
+  expect(s.tryProcess({
+    action: { row: 0, col: 1, mark: 'X' },
+    timestamp: 1040,
+    clientId: 0,
+  })).toBe(true)
+  expect(s.tryProcess({
+    action: { row: 0, col: 2, mark: 'O' },
+    timestamp: 1030,
+    clientId: 0,
+  })).toBe(true)
+  expect(s.tryProcess({
+    action: { row: 1, col: 0, mark: 'X' },
+    timestamp: 1020,
+    clientId: 0,
+  })).toBe(true)
+
+  expect(s.confirmBefore(1021)).toBe(1)
+  expect(s.confState).toEqual({
+    board: [
+      ['X', undefined, undefined],
+      ['X', undefined, undefined],
+      [undefined, undefined, undefined],
+    ],
+  })
+  expect(s.projs).toEqual([{
+    action: { row: 0, col: 2, mark: 'O' },
+    timestamp: 1030,
+    clientId: 0,
+    state: {
+      board: [
+        ['X', undefined, 'O'],
+        ['X', undefined, undefined],
+        [undefined, undefined, undefined],
+      ],
+    },
+  }, {
+    action: { row: 0, col: 1, mark: 'X' },
+    timestamp: 1040,
+    clientId: 0,
+    state: {
+      board: [
+        ['X', 'X', 'O'],
+        ['X', undefined, undefined],
+        [undefined, undefined, undefined],
+      ],
+    },
+  }])
+  expect(s.projState).toEqual({
+    board: [
+      ['X', 'X', 'O'],
+      ['X', undefined, undefined],
+      [undefined, undefined, undefined],
+    ],
+  })
+})

packages/ketchup-common/index.ts

@@ -0,0 +1,133 @@
+import EventEmitter from 'events'
+import last from 'lodash/last'
+
+interface Timed {
+  timestamp: number
+  clientId?: number
+}
+
+function compareTimed(k0: Timed, k1: Timed): number {
+  const dt = k0.timestamp - k1.timestamp
+  if (dt !== 0) {
+    return dt
+  } else if (k0.clientId === undefined) {
+    return k1.clientId === undefined ? 0 : -1
+  } else {
+    return k1.clientId === undefined ? 1 : k0.clientId - k1.clientId
+  }
+}
+
+export interface UnconfAction<Action> extends Timed {
+  action: Action
+  clientId: number
+}
+
+interface Projection<State, Action> extends UnconfAction<Action> {
+  state: State
+}
+
+/**
+ * Events: projection
+ */
+export class KetchupSynced<State, Action> extends EventEmitter {
+  projs: Projection<State, Action>[] = []
+
+  constructor(
+    public confState: State,
+    public confBefore: number,
+    readonly reducer: (state: State, action: Action) => State,
+    unconfActions: UnconfAction<Action>[] = [],
+  ) {
+    super()
+    unconfActions.forEach(a => this.tryProcess(a))
+  }
+
+  get projState(): State {
+    return last(this.projs)?.state ?? this.confState
+  }
+
+  unconfActions(): UnconfAction<Action>[] {
+    return this.projs.map(({ action, timestamp, clientId }) => ({ action, timestamp, clientId }))
+  }
+
+  tryProcess(msg: UnconfAction<Action>): boolean {
+    if (msg.timestamp < this.confBefore) {
+      return false
+    }
+    let { idx, exact } = this.indexSearch(msg)
+    if (exact) {
+      return false
+    }
+    this.projs.splice(idx, 0, {
+      ...msg,
+      state: this.reducer(this.projs[idx - 1]?.state ?? this.confState, msg.action),
+    })
+    while (++idx < this.projs.length) {
+      this.projs[idx].state = this.reducer(this.projs[idx - 1].state, this.projs[idx].action)
+    }
+    this.emit('projection', this.projState)
+    return true
+  }
+
+  confirmBefore(timestamp: number): number {
+    if (timestamp <= this.confBefore) {
+      return 0
+    }
+    const { idx: numToDel } = this.indexSearch({ timestamp })
+    if (numToDel > 0) {
+      this.confState = this.projs[numToDel - 1].state
+      this.projs.splice(0, numToDel)
+    }
+    this.confBefore = timestamp
+    return numToDel
+  }
+
+  private indexSearch(x: Timed): { idx: number, exact: boolean } {
+    let lo = 0
+    let hi = this.projs.length
+    while (lo < hi) {
+      const mid = Math.floor((lo + hi) / 2)
+      const comp = compareTimed(x, this.projs[mid])
+      if (comp === 0 ) {
+        return { idx: mid, exact: true }
+      } else if (comp > 0) {
+        lo = mid + 1
+      } else {
+        hi = mid
+      }
+    }
+    return { idx: lo, exact: false }
+  }
+}
+
+export interface ActionServerMessage<Action> extends UnconfAction<Action> {
+  message: 'action'
+}
+export interface ConfirmServerMessage {
+  message: 'confirm'
+  confBefore: number
+}
+export interface HandshakeServerMessage<State, Action> {
+  message: 'handshake'
+  clientId: number
+  confState: State
+  confBefore: number
+  unconfActions: UnconfAction<Action>[]
+}
+export type ServerMessage<State, Action> =
+  ActionServerMessage<Action> |
+  ConfirmServerMessage |
+  HandshakeServerMessage<State, Action>
+
+export interface ActionClientMessage<Action> {
+  message: 'action'
+  action: Action
+  timestamp: number
+}
+export interface HandshakeClientMessage {
+  message: 'handshake'
+  timestamp: number
+}
+export type ClientMessage<State, Action> =
+  ActionClientMessage<Action> |
+  HandshakeClientMessage

packages/ketchup-common/jest.config.js

@@ -0,0 +1,4 @@
+module.exports = {
+  preset: 'ts-jest',
+  testEnvironment: 'node',
+};

packages/ketchup-common/package.json

@@ -0,0 +1,27 @@
+{
+  "name": "ketchup-common",
+  "version": "0.1.2",
+  "description": "WebSocket-based rollback state synchronization server.",
+  "main": "dist/index.js",
+  "license": "MIT",
+  "private": true,
+  "dependencies": {
+    "lodash": "^4.17.20"
+  },
+  "devDependencies": {
+    "@tsconfig/node14": "^1.0.0",
+    "@types/jest": "^26.0.20",
+    "@types/lodash": "^4.14.168",
+    "@types/node": "^14.14.22",
+    "@typescript-eslint/eslint-plugin": "^4.14.1",
+    "@typescript-eslint/parser": "^4.14.1",
+    "eslint": "^7.18.0",
+    "jest": "^26.6.3",
+    "ts-jest": "^26.5.0",
+    "typescript": "^4.1.3"
+  },
+  "scripts": {
+    "build": "tsc",
+    "test": "tsc && jest"
+  }
+}

packages/ketchup-common/tsconfig.json

@@ -0,0 +1,7 @@
+{
+  "extends": "@tsconfig/node14/tsconfig.json",
+  "compilerOptions": {
+    "rootDir": ".",
+    "outDir": "dist"
+  }
+}

packages/ketchup-react/.eslintrc.json

@@ -0,0 +1,23 @@
+{
+    "env": {
+        "es2021": true,
+        "browser": true
+    },
+    "extends": [
+        "standard"
+    ],
+    "parser": "@typescript-eslint/parser",
+    "parserOptions": {
+        "ecmaVersion": 12,
+        "sourceType": "module"
+    },
+    "plugins": [
+        "@typescript-eslint"
+    ],
+    "rules": {
+      "comma-dangle": ["error", "only-multiline"],
+      "padded-blocks": "warn",
+      "no-multiple-empty-lines": "warn",
+      "space-before-function-paren": "off"
+    }
+}

packages/ketchup-react/index.ts

@@ -0,0 +1,22 @@
+import { useCallback, useEffect, useState } from 'react'
+import KetchupClient from 'ketchup-client'
+
+type Dispatch<Action> = (action: Action, timestamp?: number) => void
+
+export default function useKetchup<State, Action>(
+  url: string,
+  reducer: (state: State, action: Action) => State,
+): [State | undefined, Dispatch<Action>] {
+  const [proj, setProj] = useState<State>()
+  const [kc, setKc] = useState<KetchupClient<State, Action>>()
+
+  useEffect(() => {
+    const newKc = new KetchupClient(url, reducer)
+    setKc(newKc)
+    newKc.on('projection', setProj)
+    return () => { newKc.off('projection', setProj) }
+  }, [url, reducer])
+
+  const dispatch = useCallback((a, ts) => kc?.dispatch(a, ts), [kc])
+  return [proj, dispatch, /* connected */]
+}

packages/ketchup-react/package.json

@@ -0,0 +1,28 @@
+{
+  "name": "ketchup-react",
+  "version": "0.1.2",
+  "description": "WebSocket-based rollback state synchronization server.",
+  "main": "dist/index.js",
+  "license": "MIT",
+  "private": true,
+  "dependencies": {
+    "ketchup-client": "^0.1.1",
+    "ketchup-common": "^0.1.1",
+    "react": "^17.0.1"
+  },
+  "devDependencies": {
+    "@tsconfig/node14": "^1.0.0",
+    "@types/jest": "^26.0.20",
+    "@types/node": "^14.14.22",
+    "@types/react": "^17.0.0",
+    "@typescript-eslint/eslint-plugin": "^4.14.1",
+    "@typescript-eslint/parser": "^4.14.1",
+    "eslint": "^7.18.0",
+    "jest": "^26.6.3",
+    "ts-jest": "^26.5.0",
+    "typescript": "^4.1.3"
+  },
+  "scripts": {
+    "build": "tsc"
+  }
+}

packages/ketchup-react/tsconfig.json

@@ -0,0 +1,7 @@
+{
+  "extends": "@tsconfig/node14/tsconfig.json",
+  "compilerOptions": {
+    "rootDir": ".",
+    "outDir": "dist"
+  }
+}

packages/ketchup-server/.eslintrc.json

@@ -0,0 +1,23 @@
+{
+    "env": {
+        "es2021": true,
+        "node": true
+    },
+    "extends": [
+        "standard"
+    ],
+    "parser": "@typescript-eslint/parser",
+    "parserOptions": {
+        "ecmaVersion": 12,
+        "sourceType": "module"
+    },
+    "plugins": [
+        "@typescript-eslint"
+    ],
+    "rules": {
+      "comma-dangle": ["error", "only-multiline"],
+      "padded-blocks": "warn",
+      "no-multiple-empty-lines": "warn",
+      "space-before-function-paren": "off"
+    }
+}

packages/ketchup-server/index.ts

@@ -0,0 +1,108 @@
+import WebSocket from 'ws'
+import min from 'lodash/min'
+import { ActionClientMessage, KetchupSynced as KetchupSynced, ActionServerMessage, HandshakeServerMessage, ConfirmServerMessage, ClientMessage, HandshakeClientMessage } from 'ketchup-common'
+
+interface RemoteClient {
+  syncedAt?: number
+  ws: WebSocket
+  handshook: boolean
+}
+
+export default class KetchupServer<State, Action> {
+  clients = new Map<number, RemoteClient>()
+  synced: KetchupSynced<State, Action>
+  nextClientId = 0
+
+  constructor(
+    initState: State,
+    reducer: (state: State, action: Action) => State, 
+  ) {
+    this.synced = new KetchupSynced<State, Action>(
+      initState, 
+      Date.now() - 1000, // TODO: Handle clients joining with clocks running significantly behind
+      reducer,
+    )
+  }
+
+  addRemoteClient(ws: WebSocket) {
+    const clientId = this.nextClientId++
+    this.clients.set(clientId, { ws, handshook: false })
+    ws.onmessage = event => this.onMessage(clientId, JSON.parse(event.data as string) as ClientMessage<State, Action>)
+    ws.onclose = () => this.onRemoteClose(clientId)
+  }
+
+  private onMessage(clientId: number, msg: ClientMessage<State, Action>) {
+    const client = this.clients.get(clientId)
+    if (!client) {
+      return
+    }
+    switch (msg.message) {
+      case 'handshake':
+        client.syncedAt = (msg as HandshakeClientMessage).timestamp
+        client.ws.send(JSON.stringify({
+          message: 'handshake',
+          clientId,
+          confState: this.synced.confState,
+          confBefore: this.synced.confBefore,
+          unconfActions: this.synced.unconfActions(),
+        } as HandshakeServerMessage<State, Action>))
+        client.handshook = true
+        break
+
+      case 'action':
+        if (client.handshook) {
+          this.onActionMessage(clientId, msg)
+        }
+        break
+
+      default:
+        throw new Error(`Invalid message from client: ${JSON.stringify(msg)}`)
+    }
+  }
+
+  private onActionMessage(clientId: number, cMsg: ActionClientMessage<Action>) {
+    const client = this.clients.get(clientId)
+    if (client && this.synced.tryProcess({
+      clientId,
+      action: cMsg.action,
+      timestamp: cMsg.timestamp
+    })) {
+      const sMsg = JSON.stringify({
+        message: 'action',
+        clientId,
+        action: cMsg.action,
+        timestamp: cMsg.timestamp,
+      } as ActionServerMessage<Action>)
+      for (const [id, client] of this.clients) {
+        if (id !== clientId) {
+          client.ws.send(sMsg)
+        }
+      }
+
+      client.syncedAt = cMsg.timestamp
+      this.considerConfirm()
+    }
+  }
+
+  private onRemoteClose(clientId: number) {
+    if (this.clients.delete(clientId)) {
+      this.considerConfirm()
+    }
+  }
+
+  private considerConfirm() {
+    const oldestSync = min([...this.clients.values()].map(c => c.syncedAt))
+    if (oldestSync !== undefined && this.synced.confirmBefore(oldestSync) > 0) {
+      console.log('Confirming before', oldestSync)
+      const msg = JSON.stringify({
+        message: 'confirm',
+        confBefore: this.synced.confBefore,
+      } as ConfirmServerMessage)
+      for (const client of this.clients.values()) {
+        client.ws.send(msg)
+      }
+    } else {
+      console.log('Not confirming before', oldestSync)
+    }
+  }
+}

packages/ketchup-server/package.json

@@ -0,0 +1,33 @@
+{
+  "name": "ketchup-server",
+  "version": "0.1.3",
+  "description": "WebSocket-based rollback state synchronization server.",
+  "main": "dist/index.js",
+  "license": "MIT",
+  "private": true,
+  "dependencies": {
+    "ketchup-common": "^0.1.1",
+    "lodash": "^4.17.20",
+    "ws": "^7.4.2"
+  },
+  "devDependencies": {
+    "@tsconfig/node14": "^1.0.0",
+    "@types/jest": "^26.0.20",
+    "@types/lodash": "^4.14.168",
+    "@types/node": "^14.14.22",
+    "@types/ws": "^7.4.0",
+    "@typescript-eslint/eslint-plugin": "^4.14.1",
+    "@typescript-eslint/parser": "^4.14.1",
+    "eslint": "^7.18.0",
+    "jest": "^26.6.3",
+    "ts-jest": "^26.5.0",
+    "typescript": "^4.1.3"
+  },
+  "optionalDependencies": {
+    "bufferutil": "^4.0.3",
+    "utf-8-validate": "^5.0.4"
+  },
+  "scripts": {
+    "build": "tsc"
+  }
+}

packages/ketchup-server/tsconfig.json

@@ -0,0 +1,7 @@
+{
+  "extends": "@tsconfig/node14/tsconfig.json",
+  "compilerOptions": {
+    "rootDir": ".",
+    "outDir": "dist"
+  }
+}

packages/space-client/.env

@@ -0,0 +1 @@
+SKIP_PREFLIGHT_CHECK=true

packages/space-client/.gitignore

@@ -0,0 +1,23 @@
+# See https://help.github.com/articles/ignoring-files/ for more about ignoring files.
+
+# dependencies
+/node_modules
+/.pnp
+.pnp.js
+
+# testing
+/coverage
+
+# production
+/build
+
+# misc
+.DS_Store
+.env.local
+.env.development.local
+.env.test.local
+.env.production.local
+
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*

packages/space-client/README.md

@@ -0,0 +1,46 @@
+# Getting Started with Create React App
+
+This project was bootstrapped with [Create React App](https://github.com/facebook/create-react-app).
+
+## Available Scripts
+
+In the project directory, you can run:
+
+### `yarn start`
+
+Runs the app in the development mode.\
+Open [http://localhost:3000](http://localhost:3000) to view it in the browser.
+
+The page will reload if you make edits.\
+You will also see any lint errors in the console.
+
+### `yarn test`
+
+Launches the test runner in the interactive watch mode.\
+See the section about [running tests](https://facebook.github.io/create-react-app/docs/running-tests) for more information.
+
+### `yarn build`
+
+Builds the app for production to the `build` folder.\
+It correctly bundles React in production mode and optimizes the build for the best performance.
+
+The build is minified and the filenames include the hashes.\
+Your app is ready to be deployed!
+
+See the section about [deployment](https://facebook.github.io/create-react-app/docs/deployment) for more information.
+
+### `yarn eject`
+
+**Note: this is a one-way operation. Once you `eject`, you can’t go back!**
+
+If you aren’t satisfied with the build tool and configuration choices, you can `eject` at any time. This command will remove the single build dependency from your project.
+
+Instead, it will copy all the configuration files and the transitive dependencies (webpack, Babel, ESLint, etc) right into your project so you have full control over them. All of the commands except `eject` will still work, but they will point to the copied scripts so you can tweak them. At this point you’re on your own.
+
+You don’t have to ever use `eject`. The curated feature set is suitable for small and middle deployments, and you shouldn’t feel obligated to use this feature. However we understand that this tool wouldn’t be useful if you couldn’t customize it when you are ready for it.
+
+## Learn More
+
+You can learn more in the [Create React App documentation](https://facebook.github.io/create-react-app/docs/getting-started).
+
+To learn React, check out the [React documentation](https://reactjs.org/).

packages/space-client/package.json

@@ -0,0 +1,45 @@
+{
+  "name": "space-client",
+  "version": "0.1.1",
+  "private": true,
+  "dependencies": {
+    "@testing-library/jest-dom": "^5.11.4",
+    "@testing-library/react": "^11.1.0",
+    "@testing-library/user-event": "^13.1.9",
+    "@types/jest": "^26.0.15",
+    "@types/node": "^12.0.0",
+    "@types/react": "^17.0.5",
+    "@types/react-dom": "^17.0.5",
+    "ketchup-react": "^0.1.1",
+    "react": "^17.0.1",
+    "react-dom": "^17.0.1",
+    "react-scripts": "^4.0.3",
+    "space-common": "^0.1.1",
+    "typescript": "^4.0.3",
+    "web-vitals": "^1.1.2"
+  },
+  "scripts": {
+    "start": "react-scripts start",
+    "build": "react-scripts build",
+    "test": "react-scripts test",
+    "eject": "react-scripts eject"
+  },
+  "eslintConfig": {
+    "extends": [
+      "react-app",
+      "react-app/jest"
+    ]
+  },
+  "browserslist": {
+    "production": [
+      ">0.2%",
+      "not dead",
+      "not op_mini all"
+    ],
+    "development": [
+      "last 1 chrome version",
+      "last 1 firefox version",
+      "last 1 safari version"
+    ]
+  }
+}

packages/space-client/public/index.html

@@ -0,0 +1,43 @@
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <meta charset="utf-8" />
+    <link rel="icon" href="%PUBLIC_URL%/favicon.ico" />
+    <meta name="viewport" content="width=device-width, initial-scale=1" />
+    <meta name="theme-color" content="#000000" />
+    <meta
+      name="description"
+      content="Web site created using create-react-app"
+    />
+    <link rel="apple-touch-icon" href="%PUBLIC_URL%/logo192.png" />
+    <!--
+      manifest.json provides metadata used when your web app is installed on a
+      user's mobile device or desktop. See https://developers.google.com/web/fundamentals/web-app-manifest/
+    -->
+    <link rel="manifest" href="%PUBLIC_URL%/manifest.json" />
+    <!--
+      Notice the use of %PUBLIC_URL% in the tags above.
+      It will be replaced with the URL of the `public` folder during the build.
+      Only files inside the `public` folder can be referenced from the HTML.
+
+      Unlike "/favicon.ico" or "favicon.ico", "%PUBLIC_URL%/favicon.ico" will
+      work correctly both with client-side routing and a non-root public URL.
+      Learn how to configure a non-root public URL by running `npm run build`.
+    -->
+    <title>React App</title>
+  </head>
+  <body>
+    <noscript>You need to enable JavaScript to run this app.</noscript>
+    <div id="root"></div>
+    <!--
+      This HTML file is a template.
+      If you open it directly in the browser, you will see an empty page.
+
+      You can add webfonts, meta tags, or analytics to this file.
+      The build step will place the bundled scripts into the <body> tag.
+
+      To begin the development, run `npm start` or `yarn start`.
+      To create a production bundle, use `npm run build` or `yarn build`.
+    -->
+  </body>
+</html>

packages/space-client/public/manifest.json

@@ -0,0 +1,25 @@
+{
+  "short_name": "React App",
+  "name": "Create React App Sample",
+  "icons": [
+    {
+      "src": "favicon.ico",
+      "sizes": "64x64 32x32 24x24 16x16",
+      "type": "image/x-icon"
+    },
+    {
+      "src": "logo192.png",
+      "type": "image/png",
+      "sizes": "192x192"
+    },
+    {
+      "src": "logo512.png",
+      "type": "image/png",
+      "sizes": "512x512"
+    }
+  ],
+  "start_url": ".",
+  "display": "standalone",
+  "theme_color": "#000000",
+  "background_color": "#ffffff"
+}

packages/space-client/public/robots.txt

@@ -0,0 +1,3 @@
+# https://www.robotstxt.org/robotstxt.html
+User-agent: *
+Disallow:

packages/space-client/src/App.css

@@ -0,0 +1,38 @@
+.App {
+  text-align: center;
+}
+
+.App-logo {
+  height: 40vmin;
+  pointer-events: none;
+}
+
+@media (prefers-reduced-motion: no-preference) {
+  .App-logo {
+    animation: App-logo-spin infinite 20s linear;
+  }
+}
+
+.App-header {
+  background-color: #282c34;
+  min-height: 100vh;
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  justify-content: center;
+  font-size: calc(10px + 2vmin);
+  color: white;
+}
+
+.App-link {
+  color: #61dafb;
+}
+
+@keyframes App-logo-spin {
+  from {
+    transform: rotate(0deg);
+  }
+  to {
+    transform: rotate(360deg);
+  }
+}

packages/space-client/src/App.test.tsx

@@ -0,0 +1,9 @@
+import React from 'react';
+import { render, screen } from '@testing-library/react';
+import App from './App';
+
+test('renders learn react link', () => {
+  render(<App />);
+  const linkElement = screen.getByText(/learn react/i);
+  expect(linkElement).toBeInTheDocument();
+});

packages/space-client/src/App.tsx

@@ -0,0 +1,31 @@
+import React, { useState } from 'react';
+import './App.css';
+import useKetchup from 'ketchup-react'
+import { reducer } from 'space-common'
+
+export default function App() {
+  const [proj, dispatch] = useKetchup('ws://localhost:4000', reducer)
+  const [player, setPlayer] = useState<'X' | 'O'>('X')
+
+  if (!proj) {
+    return <>Loading</>
+  } else {
+    return <>
+      <p>Playing as {player} <button onClick={() => setPlayer(player === 'X' ? 'O' : 'X')}>Change</button></p>
+      <table><tbody>
+        {proj.board.map((row, rIdx) =>
+          <tr key={rIdx}>
+            {row.map((mark, cIdx) =>
+              <td key={cIdx}>
+                {mark ??
+                  <button onClick={() => dispatch({ type: 'play', row: rIdx, column: cIdx, mark: player })}></button>
+                }
+              </td>
+            )}
+          </tr>
+        )}
+      </tbody></table>
+      <button onClick={() => dispatch({ type: 'reset' })}>Reset</button>
+    </>
+  }
+}

packages/space-client/src/index.css

@@ -0,0 +1,13 @@
+body {
+  margin: 0;
+  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen',
+    'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue',
+    sans-serif;
+  -webkit-font-smoothing: antialiased;
+  -moz-osx-font-smoothing: grayscale;
+}
+
+code {
+  font-family: source-code-pro, Menlo, Monaco, Consolas, 'Courier New',
+    monospace;
+}

packages/space-client/src/index.tsx

@@ -0,0 +1,17 @@
+import React from 'react';
+import ReactDOM from 'react-dom';
+import './index.css';
+import App from './App';
+import reportWebVitals from './reportWebVitals';
+
+ReactDOM.render(
+  <React.StrictMode>
+    <App />
+  </React.StrictMode>,
+  document.getElementById('root')
+);
+
+// If you want to start measuring performance in your app, pass a function
+// to log results (for example: reportWebVitals(console.log))
+// or send to an analytics endpoint. Learn more: https://bit.ly/CRA-vitals
+reportWebVitals();

packages/space-client/src/logo.svg

@@ -0,0 +1 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 841.9 595.3"><g fill="#61DAFB"><path d="M666.3 296.5c0-32.5-40.7-63.3-103.1-82.4 14.4-63.6 8-114.2-20.2-130.4-6.5-3.8-14.1-5.6-22.4-5.6v22.3c4.6 0 8.3.9 11.4 2.6 13.6 7.8 19.5 37.5 14.9 75.7-1.1 9.4-2.9 19.3-5.1 29.4-19.6-4.8-41-8.5-63.5-10.9-13.5-18.5-27.5-35.3-41.6-50 32.6-30.3 63.2-46.9 84-46.9V78c-27.5 0-63.5 19.6-99.9 53.6-36.4-33.8-72.4-53.2-99.9-53.2v22.3c20.7 0 51.4 16.5 84 46.6-14 14.7-28 31.4-41.3 49.9-22.6 2.4-44 6.1-63.6 11-2.3-10-4-19.7-5.2-29-4.7-38.2 1.1-67.9 14.6-75.8 3-1.8 6.9-2.6 11.5-2.6V78.5c-8.4 0-16 1.8-22.6 5.6-28.1 16.2-34.4 66.7-19.9 130.1-62.2 19.2-102.7 49.9-102.7 82.3 0 32.5 40.7 63.3 103.1 82.4-14.4 63.6-8 114.2 20.2 130.4 6.5 3.8 14.1 5.6 22.5 5.6 27.5 0 63.5-19.6 99.9-53.6 36.4 33.8 72.4 53.2 99.9 53.2 8.4 0 16-1.8 22.6-5.6 28.1-16.2 34.4-66.7 19.9-130.1 62-19.1 102.5-49.9 102.5-82.3zm-130.2-66.7c-3.7 12.9-8.3 26.2-13.5 39.5-4.1-8-8.4-16-13.1-24-4.6-8-9.5-15.8-14.4-23.4 14.2 2.1 27.9 4.7 41 7.9zm-45.8 106.5c-7.8 13.5-15.8 26.3-24.1 38.2-14.9 1.3-30 2-45.2 2-15.1 0-30.2-.7-45-1.9-8.3-11.9-16.4-24.6-24.2-38-7.6-13.1-14.5-26.4-20.8-39.8 6.2-13.4 13.2-26.8 20.7-39.9 7.8-13.5 15.8-26.3 24.1-38.2 14.9-1.3 30-2 45.2-2 15.1 0 30.2.7 45 1.9 8.3 11.9 16.4 24.6 24.2 38 7.6 13.1 14.5 26.4 20.8 39.8-6.3 13.4-13.2 26.8-20.7 39.9zm32.3-13c5.4 13.4 10 26.8 13.8 39.8-13.1 3.2-26.9 5.9-41.2 8 4.9-7.7 9.8-15.6 14.4-23.7 4.6-8 8.9-16.1 13-24.1zM421.2 430c-9.3-9.6-18.6-20.3-27.8-32 9 .4 18.2.7 27.5.7 9.4 0 18.7-.2 27.8-.7-9 11.7-18.3 22.4-27.5 32zm-74.4-58.9c-14.2-2.1-27.9-4.7-41-7.9 3.7-12.9 8.3-26.2 13.5-39.5 4.1 8 8.4 16 13.1 24 4.7 8 9.5 15.8 14.4 23.4zM420.7 163c9.3 9.6 18.6 20.3 27.8 32-9-.4-18.2-.7-27.5-.7-9.4 0-18.7.2-27.8.7 9-11.7 18.3-22.4 27.5-32zm-74 58.9c-4.9 7.7-9.8 15.6-14.4 23.7-4.6 8-8.9 16-13 24-5.4-13.4-10-26.8-13.8-39.8 13.1-3.1 26.9-5.8 41.2-7.9zm-90.5 125.2c-35.4-15.1-58.3-34.9-58.3-50.6 0-15.7 22.9-35.6 58.3-50.6 8.6-3.7 18-7 27.7-10.1 5.7 19.6 13.2 40 22.5 60.9-9.2 20.8-16.6 41.1-22.2 60.6-9.9-3.1-19.3-6.5-28-10.2zM310 490c-13.6-7.8-19.5-37.5-14.9-75.7 1.1-9.4 2.9-19.3 5.1-29.4 19.6 4.8 41 8.5 63.5 10.9 13.5 18.5 27.5 35.3 41.6 50-32.6 30.3-63.2 46.9-84 46.9-4.5-.1-8.3-1-11.3-2.7zm237.2-76.2c4.7 38.2-1.1 67.9-14.6 75.8-3 1.8-6.9 2.6-11.5 2.6-20.7 0-51.4-16.5-84-46.6 14-14.7 28-31.4 41.3-49.9 22.6-2.4 44-6.1 63.6-11 2.3 10.1 4.1 19.8 5.2 29.1zm38.5-66.7c-8.6 3.7-18 7-27.7 10.1-5.7-19.6-13.2-40-22.5-60.9 9.2-20.8 16.6-41.1 22.2-60.6 9.9 3.1 19.3 6.5 28.1 10.2 35.4 15.1 58.3 34.9 58.3 50.6-.1 15.7-23 35.6-58.4 50.6zM320.8 78.4z"/><circle cx="420.9" cy="296.5" r="45.7"/><path d="M520.5 78.1z"/></g></svg>

packages/space-client/src/react-app-env.d.ts

@@ -0,0 +1 @@
+/// <reference types="react-scripts" />

packages/space-client/src/reportWebVitals.ts

@@ -0,0 +1,15 @@
+import { ReportHandler } from 'web-vitals';
+
+const reportWebVitals = (onPerfEntry?: ReportHandler) => {
+  if (onPerfEntry && onPerfEntry instanceof Function) {
+    import('web-vitals').then(({ getCLS, getFID, getFCP, getLCP, getTTFB }) => {
+      getCLS(onPerfEntry);
+      getFID(onPerfEntry);
+      getFCP(onPerfEntry);
+      getLCP(onPerfEntry);
+      getTTFB(onPerfEntry);
+    });
+  }
+};
+
+export default reportWebVitals;

packages/space-client/src/setupTests.ts

@@ -0,0 +1,5 @@
+// jest-dom adds custom jest matchers for asserting on DOM nodes.
+// allows you to do things like:
+// expect(element).toHaveTextContent(/react/i)
+// learn more: https://github.com/testing-library/jest-dom
+import '@testing-library/jest-dom';

packages/space-client/tsconfig.json

@@ -0,0 +1,26 @@
+{
+  "compilerOptions": {
+    "target": "esnext",
+    "lib": [
+      "dom",
+      "dom.iterable",
+      "esnext"
+    ],
+    "allowJs": true,
+    "skipLibCheck": true,
+    "esModuleInterop": true,
+    "allowSyntheticDefaultImports": true,
+    "strict": true,
+    "forceConsistentCasingInFileNames": true,
+    "noFallthroughCasesInSwitch": true,
+    "module": "esnext",
+    "moduleResolution": "node",
+    "resolveJsonModule": true,
+    "isolatedModules": true,
+    "noEmit": true,
+    "jsx": "react-jsx"
+  },
+  "include": [
+    "src"
+  ]
+}

packages/space-common/.eslintrc.json

@@ -0,0 +1,24 @@
+{
+    "env": {
+        "es2021": true,
+        "node": true,
+        "browser": true
+    },
+    "extends": [
+        "standard"
+    ],
+    "parser": "@typescript-eslint/parser",
+    "parserOptions": {
+        "ecmaVersion": 12,
+        "sourceType": "module"
+    },
+    "plugins": [
+        "@typescript-eslint"
+    ],
+    "rules": {
+      "comma-dangle": ["error", "only-multiline"],
+      "padded-blocks": "warn",
+      "no-multiple-empty-lines": "warn",
+      "space-before-function-paren": "off"
+    }
+}

packages/space-common/index.ts

@@ -0,0 +1,42 @@
+export interface State {
+  board: ('X' | 'O' | null)[][]
+}
+
+export const initial: State = {
+  board: [
+    [null, null, null],    
+    [null, null, null],    
+    [null, null, null],    
+  ]
+}
+
+export interface BaseAction {
+  type: string
+}
+export interface PlayAction extends BaseAction {
+  type: 'play'
+  row: number
+  column: number
+  mark: 'X' | 'O'
+}
+export interface ResetAction extends BaseAction {
+  type: 'reset'
+}
+export type Action = PlayAction | ResetAction
+
+export function reducer(state: State, action: Action): State {
+  switch (action.type) {
+  case 'play':
+    const playAction = action as PlayAction
+    return {
+      board: state.board.map((row, rIdx) => 
+        rIdx !== playAction.row ? row : row.map((cell, cIdx) =>
+          cIdx !== playAction.column ? cell : playAction.mark
+        )
+      )
+    }
+  case 'reset':
+    return initial
+  }
+  //throw new Error('Unknown action type')
+}

packages/space-common/package.json

@@ -0,0 +1,27 @@
+{
+  "name": "space-common",
+  "version": "0.1.3",
+  "description": "WebSocket-based rollback state synchronization server.",
+  "main": "dist/index.js",
+  "license": "MIT",
+  "private": true,
+  "dependencies": {
+    "ketchup-common": "^0.1.1",
+    "lodash": "^4.17.20"
+  },
+  "devDependencies": {
+    "@tsconfig/node14": "^1.0.0",
+    "@types/jest": "^26.0.20",
+    "@types/lodash": "^4.14.168",
+    "@types/node": "^14.14.22",
+    "@typescript-eslint/eslint-plugin": "^4.14.1",
+    "@typescript-eslint/parser": "^4.14.1",
+    "eslint": "^7.18.0",
+    "jest": "^26.6.3",
+    "ts-jest": "^26.5.0",
+    "typescript": "^4.1.3"
+  },
+  "scripts": {
+    "build": "tsc"
+  }
+}

packages/space-common/tsconfig.json

@@ -0,0 +1,7 @@
+{
+  "extends": "@tsconfig/node14/tsconfig.json",
+  "compilerOptions": {
+    "rootDir": ".",
+    "outDir": "dist"
+  }
+}

packages/space-server/.eslintrc.json

@@ -0,0 +1,23 @@
+{
+    "env": {
+        "es2021": true,
+        "node": true
+    },
+    "extends": [
+        "standard"
+    ],
+    "parser": "@typescript-eslint/parser",
+    "parserOptions": {
+        "ecmaVersion": 12,
+        "sourceType": "module"
+    },
+    "plugins": [
+        "@typescript-eslint"
+    ],
+    "rules": {
+      "comma-dangle": ["error", "only-multiline"],
+      "padded-blocks": "warn",
+      "no-multiple-empty-lines": "warn",
+      "space-before-function-paren": "off"
+    }
+}

packages/space-server/index.ts

@@ -0,0 +1,22 @@
+import WebSocket from 'ws'
+import KetchupServer from 'ketchup-server'
+import { initial, reducer } from 'space-common'
+
+const port = parseInt(process.env.PORT ?? '80')
+
+const wss = new WebSocket.Server({ port })
+
+const ks = new KetchupServer(initial, reducer)
+
+wss.on('connection', ws => {
+  ks.addRemoteClient(ws)
+})
+
+console.log(`Listening on ${port}`)
+
+function shutdown() {
+  console.log('Shutting down')
+  wss.close()
+}
+process.on('SIGINT', shutdown)
+process.on('SIGTERM', shutdown)

packages/space-server/package.json

@@ -0,0 +1,36 @@
+{
+  "name": "space-server",
+  "version": "0.1.3",
+  "description": "WebSocket-based rollback state synchronization server.",
+  "main": "dist/index.js",
+  "license": "MIT",
+  "private": true,
+  "dependencies": {
+    "ketchup-server": "^0.1.1",
+    "lodash": "^4.17.20",
+    "space-common": "^0.1.1",
+    "ts-node": "^9.1.1",
+    "ws": "^7.4.2"
+  },
+  "devDependencies": {
+    "@tsconfig/node14": "^1.0.0",
+    "@types/jest": "^26.0.20",
+    "@types/lodash": "^4.14.168",
+    "@types/node": "^14.14.22",
+    "@types/ws": "^7.4.0",
+    "@typescript-eslint/eslint-plugin": "^4.14.1",
+    "@typescript-eslint/parser": "^4.14.1",
+    "eslint": "^7.18.0",
+    "jest": "^26.6.3",
+    "ts-jest": "^26.5.0",
+    "typescript": "^4.1.3"
+  },
+  "optionalDependencies": {
+    "bufferutil": "^4.0.3",
+    "utf-8-validate": "^5.0.4"
+  },
+  "scripts": {
+    "build": "tsc",
+    "start": "node dist"
+  }
+}

packages/space-server/tsconfig.json

@@ -0,0 +1,7 @@
+{
+  "extends": "@tsconfig/node14/tsconfig.json",
+  "compilerOptions": {
+    "rootDir": ".",
+    "outDir": "dist"
+  }
+}