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spacetimedb-typescript

spacetimedb-typescript

github.com/douglance开发038 次安装39 周前更新
代码仓库

关于 spacetimedb-typescript

spacetimedb-typescript 是用于构建 SpacetimeDB 模块类型安全 TypeScript 客户端的技能与参考资料,涵盖生成绑定、订阅同步数据、响应式更新及常见 API 陷阱。

主要功能

  1. 01生成 TypeScript 绑定
  2. 02连接 SpacetimeDB 模块
  3. 03订阅经 SQL 筛选的表数据
  4. 04处理实时表变更事件
  5. 05提供 React hooks 和 provider
  6. 06说明 API 陷阱与约束

适用场景

  1. 01构建使用 SpacetimeDB 数据的 TypeScript 应用
  2. 02保持客户端表状态同步
  3. 03创建响应式 React 界面

安装

复制下面的命令,在终端中运行。

$npx skills add https://github.com/douglance/spacetimedb --skill spacetimedb-typescript

安装后在 Claude Code 中输入/spacetimedb-typescript确认已加载。

详细介绍

SpacetimeDB TypeScript SDK

构建可直接连接到 SpacetimeDB 模块的实时 TypeScript 客户端。SDK 为 Web 应用、Node.js、Deno、Bun 及其他 JavaScript 运行时提供类型安全的数据库访问、自动同步和响应式更新。


虚构的 API——切勿使用

这些 API 并不存在。LLM 经常会虚构它们。

// WRONG PACKAGE — does not exist
import { SpacetimeDBClient } from "@clockworklabs/spacetimedb-sdk";

// WRONG — these methods don't exist
SpacetimeDBClient.connect(...);
SpacetimeDBClient.call("reducer_name", [...]);
connection.call("reducer_name", [arg1, arg2]);

// WRONG — positional reducer arguments
conn.reducers.doSomething("value");  // WRONG!
正确模式:
// CORRECT IMPORTS
import { DbConnection, tables } from './module_bindings';  // Generated!
import { SpacetimeDBProvider, useTable, Identity } from 'spacetimedb/react';

// CORRECT REDUCER CALLS — object syntax, not positional!
conn.reducers.doSomething({ value: 'test' });
conn.reducers.updateItem({ itemId: 1n, newValue: 42 });

// CORRECT DATA ACCESS — useTable returns [rows, isLoading]
const [items, isLoading] = useTable(tables.item);
切勿:
  • 虚构 Hook,例如 useItems()、useData()——使用 useTable(tables.tableName)
  • 从虚假软件包导入——仅使用 spacetimedb、spacetimedb/react、./module_bindings

常见错误表

服务端错误
错误写法正确写法错误
缺少 package.json创建 package.json"could not detect language"
缺少 tsconfig.json创建 tsconfig.json"TsconfigNotFound"
入口文件不在 src/index.ts使用 src/index.ts模块无法打包
在 COLUMNS(第 2 个参数)中设置 indexes在 OPTIONS(第 1 个参数)中设置 indexes"reading 'tag'" 错误
索引未指定 algorithmalgorithm: 'btree'"reading 'tag'" 错误
filter({ ownerId })filter(ownerId)"does not exist in type 'Range'"
对唯一列使用 .filter()对唯一列使用 .find()TypeError
insert({ ...without id })insert({ id: 0n, ... })"Property 'id' is missing"
const id = table.insert(...)const row = table.insert(...).insert() 返回行,而非 ID
.unique() + 显式索引仅使用 .unique()"name is used for multiple entities"
从 index.ts 导入 spacetimedb从 schema.ts 导入"Cannot access before initialization"
多列索引 .filter()使用单列索引PANIC 或静默返回空结果
在视图中使用 .iter()仅使用索引查找视图无法扫描表
在过程函数中使用 ctx.dbctx.withTx(tx => tx.db...)过程函数需要显式事务
在过程事务中使用 ctx.myTabletx.db.myTable上下文变量错误
客户端错误
错误写法正确写法错误
@spacetimedb/sdkspacetimedb404 / 子路径缺失
conn.reducers.foo("val")conn.reducers.foo({ param: "val" })Reducer 语法错误
内联 connectionBuilderuseMemo(() => ..., [])每次渲染都会重新连接
const rows = useTable(table)const [rows, isLoading] = useTable(table)元组解构
乐观 UI 更新让订阅驱动状态同步问题
<SpacetimeDBProvider builder={...}>connectionBuilder={...}Prop 名称错误

硬性要求

  1. 切勿编辑生成的绑定——使用 spacetime generate 重新生成
  2. Reducers 是事务性的——不会返回数据
  3. Reducers 必须是确定性的——不能使用文件系统、网络、计时器或随机数
  4. 调用 Reducer 时使用对象语法——{ param: 'value' },而非位置参数
  5. 从 ./module_bindings 导入 DbConnection——不要从 spacetimedb 导入
  6. useTable 返回一个元组——const [rows, isLoading] = useTable(tables.myTable)
  7. 对 connectionBuilder 使用记忆化——用 useMemo(() => ..., []) 包装,避免重新连接
  8. 视图只能使用索引查找——视图中不允许使用 .iter()

安装

npm install spacetimedb
# or
pnpm add spacetimedb
# or
yarn add spacetimedb

对于 Node.js 18-21,请安装 undici 对等依赖:

npm install spacetimedb undici

Node.js 22+ 和浏览器环境开箱即用。

生成类型绑定

使用 SDK 之前,请从 SpacetimeDB 模块生成 TypeScript 绑定:

spacetime generate --lang typescript --out-dir ./src/module_bindings --project-path ./server

这会创建一个 module_bindings 目录,其中包含:

  • index.ts——包括 DbConnection、tables、reducers、query 在内的主要导出
  • 每个表的类型定义(例如,player_table.ts、user_table.ts)
  • 每个 Reducer 的类型定义(例如,create_player_reducer.ts)
  • 自定义类型定义(例如,point_type.ts)

基本连接设置

import { DbConnection } from './module_bindings';

const connection = DbConnection.builder()
  .withUri('ws://localhost:3000')
  .withModuleName('my_database')
  .onConnect((conn, identity, token) => {
    console.log('Connected with identity:', identity.toHexString());

    // Store token for reconnection
    localStorage.setItem('spacetimedb_token', token);

    // Subscribe to tables after connection
    conn.subscriptionBuilder().subscribe('SELECT * FROM player');
  })
  .onDisconnect((ctx) => {
    console.log('Disconnected');
  })
  .onConnectError((ctx, error) => {
    console.error('Connection error:', error);
  })
  .build();

Connection Builder 选项

DbConnection.builder()
  // Required: SpacetimeDB server URI
  .withUri('ws://localhost:3000')

  // Required: Database module name or address
  .withModuleName('my_database')

  // Optional: Authentication token for reconnection
  .withToken(localStorage.getItem('spacetimedb_token') ?? undefined)

  // Optional: Enable compression (default: 'gzip')
  .withCompression('gzip')  // or 'none'

  // Optional: Light mode reduces network traffic
  .withLightMode(true)

  // Optional: Wait for durable writes before receiving updates
  .withConfirmedReads(true)

  // Connection lifecycle callbacks
  .onConnect((conn, identity, token) => { /* ... */ })
  .onDisconnect((ctx, error) => { /* ... */ })
  .onConnectError((ctx, error) => { /* ... */ })

  .build();

订阅表

订阅会将表数据同步到客户端缓存。使用 SQL 查询筛选你接收的数据。

基本订阅
connection.subscriptionBuilder()
  .onApplied((ctx) => {
    console.log('Subscription applied, cache is ready');
  })
  .onError((ctx, error) => {
    console.error('Subscription error:', error);
  })
  .subscribe('SELECT * FROM player');
多个查询
connection.subscriptionBuilder()
  .subscribe([
    'SELECT * FROM player',
    'SELECT * FROM game_state',
    'SELECT * FROM message WHERE room_id = 1'
  ]);
类型化查询构建器

使用生成的 query 对象进行类型安全的查询:

import { query } from './module_bindings';

// Simple query - selects all rows
connection.subscriptionBuilder()
  .subscribe(query.player.build());

// Query with WHERE clause
connection.subscriptionBuilder()
  .subscribe(
    query.player
      .where(row => row.name.eq('Alice'))
      .build()
  );

// Complex conditions
connection.subscriptionBuilder()
  .subscribe(
    query.player
      .where(row => row.score.gte(100))
      .where(row => row.isActive.eq(true))
      .build()
  );
订阅所有表

适用于开发或小型数据集:

connection.subscriptionBuilder().subscribeToAllTables();
取消订阅
const handle = connection.subscriptionBuilder()
  .onApplied(() => console.log('Subscribed'))
  .subscribe('SELECT * FROM player');

// Later, unsubscribe
handle.unsubscribe();

// Or with callback when complete
handle.unsubscribeThen((ctx) => {
  console.log('Unsubscribed successfully');
});

访问表数据

订阅后,通过 connection.db 访问缓存的数据:

// Iterate all rows
for (const player of connection.db.player.iter()) {
  console.log(player.name, player.score);
}

// Convert to array
const players = Array.from(connection.db.player.iter());

// Count rows
const count = connection.db.player.count();

// Find by primary key (if table has one)
const player = connection.db.player.id.find(42);

// Find by indexed column
const alice = connection.db.player.name.find('Alice');

表事件回调

监听表数据的实时变更:

// Row inserted
connection.db.player.onInsert((ctx, player) => {
  console.log('New player:', player.name);
});

// Row deleted
connection.db.player.onDelete((ctx, player) => {
  console.log('Player left:', player.name);
});

// Row updated (requires primary key on table)
connection.db.player.onUpdate((ctx, oldPlayer, newPlayer) => {
  console.log(`${oldPlayer.name} score: ${oldPlayer.score} -> ${newPlayer.score}`);
});

// Remove callbacks
const onInsertCb = (ctx, player) => console.log(player);
connection.db.player.onInsert(onInsertCb);
connection.db.player.removeOnInsert(onInsertCb);
事件上下文

回调会收到一个 EventContext,其中包含事件相关信息:

connection.db.player.onInsert((ctx, player) => {
  // Access to database
  const allPlayers = Array.from(ctx.db.player.iter());

  // Check event type
  if (ctx.event.tag === 'Reducer') {
    const { callerIdentity, reducer, status } = ctx.event.value;
    console.log(`Triggered by reducer: ${reducer.name}`);
  }

  // Call other reducers
  ctx.reducers.sendMessage({ playerId: player.id, text: 'Welcome!' });
});

调用 Reducer

Reducer 是用于修改数据库的服务端函数。重要:使用对象语法,而非位置参数。

// CORRECT: Object syntax
connection.reducers.createPlayer({ name: 'Alice', location: { x: 0, y: 0 } });

// WRONG: Positional arguments
// connection.reducers.createPlayer('Alice', { x: 0, y: 0 });  // DO NOT DO THIS

// Listen for reducer results
connection.reducers.onCreatePlayer((ctx, args) => {
  const { callerIdentity, status, timestamp, energyConsumed } = ctx.event;

  if (status.tag === 'Committed') {
    console.log('Player created successfully');
  } else if (status.tag === 'Failed') {
    console.error('Failed:', status.value);
  }
});

// Remove reducer callback
connection.reducers.removeOnCreatePlayer(callback);
从 snake_case 转换为 camelCase
  • 服务端:spacetimedb.reducer('do_something', ...)
  • 客户端:conn.reducers.doSomething({ ... })
Reducer 标志

控制服务端如何处理 reducer 调用:

// NoSuccessNotify: Don't send TransactionUpdate on success (reduces traffic)
connection.setReducerFlags.movePlayer('NoSuccessNotify');

// FullUpdate: Always send full TransactionUpdate (default)
connection.setReducerFlags.movePlayer('FullUpdate');

视图

视图根据已连接的用户提供对私有表数据的筛选访问。

ViewContext 与 AnonymousViewContext
// ViewContext — has ctx.sender, result varies per user (computed per-subscriber)
spacetimedb.view({ name: 'my_items', public: true }, t.array(Item.rowType), (ctx) => {
  return [...ctx.db.item.by_owner.filter(ctx.sender)];
});

// AnonymousViewContext — no ctx.sender, same result for everyone (shared, better perf)
spacetimedb.anonymousView({ name: 'leaderboard', public: true }, t.array(LeaderboardRow), (ctx) => {
  return [...ctx.db.player.by_score.filter(/* top scores */)];
});
重要:视图只能使用索引查找
// WRONG — views cannot use .iter()
spacetimedb.view(
  { name: 'my_data_wrong', public: true },
  t.array(PrivateData.rowType),
  (ctx) => [...ctx.db.privateData.iter()]  // NOT ALLOWED
);

// RIGHT — use index lookup
spacetimedb.view(
  { name: 'my_data', public: true },
  t.array(PrivateData.rowType),
  (ctx) => [...ctx.db.privateData.by_owner.filter(ctx.sender)]
);
订阅视图

视图需要显式订阅:

conn.subscriptionBuilder().subscribe([
  'SELECT * FROM public_table',
  'SELECT * FROM my_data',  // Views need explicit SQL!
]);

Procedures(Beta 版)

Procedures 用于执行副作用(HTTP 请求等),这些操作是 reducer 无法完成的。

Procedures 目前处于 Beta 阶段。API 可能会变更。

定义 procedure
spacetimedb.procedure(
  'fetch_external_data',
  { url: t.string() },
  t.string(),  // return type
  (ctx, { url }) => {
    const response = ctx.http.fetch(url);
    return response.text();
  }
);
重要:在 procedures 中访问数据库

Procedures 没有 ctx.db。使用 ctx.withTx() 访问数据库。

spacetimedb.procedure('save_fetched_data', { url: t.string() }, t.unit(), (ctx, { url }) => {
  // Fetch external data (outside transaction)
  const response = ctx.http.fetch(url);
  const data = response.text();

  // WRONG — ctx.db doesn't exist in procedures
  // ctx.db.myTable.insert({ ... });

  // RIGHT — use ctx.withTx() for database access
  ctx.withTx(tx => {
    tx.db.myTable.insert({
      id: 0n,
      content: data,
      fetchedAt: tx.timestamp,
      fetchedBy: tx.sender,
    });
  });

  return {};
});
与 reducer 的主要区别
ReducerProcedure
可直接使用 ctx.db必须使用 ctx.withTx(tx => tx.db...)
自动事务手动管理事务
不支持 HTTP/网络可使用 ctx.http.fetch()
不会向调用方返回值可以向调用方返回数据

身份与身份验证

import { Identity } from 'spacetimedb';

// Get current identity
const identity = connection.identity;
console.log(identity?.toHexString());

// Compare identities
if (identity?.isEqual(otherIdentity)) {
  console.log('Same user');
}

// Create from hex string
const parsed = Identity.fromString('0x1234...');

// Zero identity
const zero = Identity.zero();

// Compare identities using toHexString()
const isOwner = row.ownerId.toHexString() === myIdentity.toHexString();
持久化身份验证信息
// On connect, save the token
.onConnect((conn, identity, token) => {
  localStorage.setItem('auth_token', token);
  localStorage.setItem('identity', identity.toHexString());
})

// On reconnect, use saved token
.withToken(localStorage.getItem('auth_token') ?? undefined)
过期令牌处理
const onConnectError = (_ctx: ErrorContext, err: Error) => {
  if (err.message?.includes('Unauthorized') || err.message?.includes('401')) {
    localStorage.removeItem('auth_token');
    window.location.reload();
  }
};

React 集成

SDK 提供用于响应式 UI 更新的 React Hooks。

Provider 设置
import React, { useMemo } from 'react';
import ReactDOM from 'react-dom/client';
import { SpacetimeDBProvider } from 'spacetimedb/react';
import { DbConnection, query } from './module_bindings';
import App from './App';

function Root() {
  // CRITICAL: Memoize to prevent reconnects on every render
  const connectionBuilder = useMemo(() =>
    DbConnection.builder()
      .withUri('ws://localhost:3000')
      .withModuleName('my_game')
      .withToken(localStorage.getItem('auth_token') || undefined)
      .onConnect((conn, identity, token) => {
        console.log('Connected:', identity.toHexString());
        localStorage.setItem('auth_token', token);
        conn.subscriptionBuilder().subscribe(query.player.build());
      })
      .onDisconnect(() => console.log('Disconnected'))
      .onConnectError((ctx, err) => console.error('Error:', err)),
    []  // Empty deps - only create once
  );

  return (
    <SpacetimeDBProvider connectionBuilder={connectionBuilder}>
      <App />
    </SpacetimeDBProvider>
  );
}

ReactDOM.createRoot(document.getElementById('root')!).render(
  <React.StrictMode>
    <Root />
  </React.StrictMode>
);
useSpacetimeDB Hook

访问连接状态:

import { useSpacetimeDB } from 'spacetimedb/react';

function ConnectionStatus() {
  const { isActive, identity, token, connectionId, connectionError } = useSpacetimeDB();

  if (connectionError) {
    return <div>Error: {connectionError.message}</div>;
  }

  if (!isActive) {
    return <div>Connecting...</div>;
  }

  return <div>Connected as {identity?.toHexString()}</div>;
}
useTable Hook

订阅表数据并接收响应式更新。重要:返回一个元组 [rows, isLoading]。

import { useTable, where, eq } from 'spacetimedb/react';
import { tables } from './module_bindings';

function PlayerList() {
  // CORRECT: Tuple destructuring
  const [players, isLoading] = useTable(tables.player);

  if (isLoading) return <div>Loading...</div>;

  return (
    <ul>
      {players.map(player => (
        <li key={player.id}>{player.name}: {player.score}</li>
      ))}
    </ul>
  );
}

function FilteredPlayerList() {
  // Filtered players with callbacks
  const [activePlayers, isLoading] = useTable(
    tables.player,
    where(eq('isActive', true)),
    {
      onInsert: (player) => console.log('Player joined:', player.name),
      onDelete: (player) => console.log('Player left:', player.name),
      onUpdate: (oldPlayer, newPlayer) => {
        console.log(`${oldPlayer.name} updated`);
      },
    }
  );

  return (
    <ul>
      {activePlayers.map(player => (
        <li key={player.id}>{player.name}</li>
      ))}
    </ul>
  );
}
useReducer Hook

从组件中调用 reducer:

import { useReducer } from 'spacetimedb/react';
import { reducers } from './module_bindings';

function CreatePlayerForm() {
  const createPlayer = useReducer(reducers.createPlayer);
  const [name, setName] = useState('');

  const handleSubmit = (e) => {
    e.preventDefault();
    // CORRECT: Object syntax
    createPlayer({ name, location: { x: 0, y: 0 } });
    setName('');
  };

  return (
    <form onSubmit={handleSubmit}>
      <input value={name} onChange={e => setName(e.target.value)} />
      <button type="submit">Create Player</button>
    </form>
  );
}

Vue 集成

SDK 提供 Vue 组合式函数:

import { SpacetimeDBProvider, useSpacetimeDB, useTable, useReducer } from 'spacetimedb/vue';

用法与 React Hooks 类似。

Svelte 集成

SDK 提供 Svelte Stores:

import { SpacetimeDBProvider, useSpacetimeDB, useTable, useReducer } from 'spacetimedb/svelte';

服务端用法(Node.js、Deno、Bun)

SDK 可在服务端 JavaScript 运行时中使用:

import { DbConnection } from './module_bindings';

async function main() {
  const connection = DbConnection.builder()
    .withUri('ws://localhost:3000')
    .withModuleName('my_database')
    .onConnect((conn, identity, token) => {
      console.log('Connected:', identity.toHexString());

      conn.subscriptionBuilder()
        .onApplied(() => {
          // Process data
          for (const player of conn.db.player.iter()) {
            console.log(player);
          }
        })
        .subscribe('SELECT * FROM player');
    })
    .build();
}

main();

时间戳

服务端
import { Timestamp, ScheduleAt } from 'spacetimedb';

// Current time
ctx.db.item.insert({ id: 0n, createdAt: ctx.timestamp });

// Future time (add microseconds)
const future = ctx.timestamp.microsSinceUnixEpoch + 300_000_000n;  // 5 minutes
客户端(重要)

时间戳是对象,而非数字:

// WRONG
const date = new Date(row.createdAt);
const date = new Date(Number(row.createdAt / 1000n));

// RIGHT
const date = new Date(Number(row.createdAt.microsSinceUnixEpoch / 1000n));
客户端上的 ScheduleAt
// ScheduleAt is a tagged union
if (scheduleAt.tag === 'Time') {
  const date = new Date(Number(scheduleAt.value.microsSinceUnixEpoch / 1000n));
}

定时表

// Scheduled table MUST use scheduledId and scheduledAt columns
export const CleanupJob = table({
  name: 'cleanup_job',
  scheduled: 'run_cleanup'  // reducer name
}, {
  scheduledId: t.u64().primaryKey().autoInc(),
  scheduledAt: t.scheduleAt(),
  targetId: t.u64(),  // Your custom data
});

// Scheduled reducer receives full row as arg
spacetimedb.reducer('run_cleanup', { arg: CleanupJob.rowType }, (ctx, { arg }) => {
  // arg.scheduledId, arg.targetId available
  // Row is auto-deleted after reducer completes
});

// Schedule a job
import { ScheduleAt } from 'spacetimedb';
const futureTime = ctx.timestamp.microsSinceUnixEpoch + 60_000_000n; // 60 seconds
ctx.db.cleanupJob.insert({
  scheduledId: 0n,
  scheduledAt: ScheduleAt.time(futureTime),
  targetId: someId
});

// Cancel a job by deleting the row
ctx.db.cleanupJob.scheduledId.delete(jobId);

错误处理

连接错误
DbConnection.builder()
  .onConnectError((ctx, error) => {
    console.error('Failed to connect:', error.message);

    // Implement retry logic
    setTimeout(() => {
      // Rebuild connection
    }, 5000);
  })
  .build();
订阅错误
connection.subscriptionBuilder()
  .onError((ctx, error) => {
    console.error('Subscription failed:', error.message);
  })
  .subscribe('SELECT * FROM player');
Reducer 错误
connection.reducers.onCreatePlayer((ctx, args) => {
  const { status } = ctx.event;

  switch (status.tag) {
    case 'Committed':
      console.log('Success');
      break;
    case 'Failed':
      console.error('Reducer failed:', status.value);
      break;
    case 'OutOfEnergy':
      console.error('Out of energy');
      break;
  }
});

断开连接

// Gracefully disconnect
connection.disconnect();

类型参考

核心类型
import {
  Identity,           // User identity (256-bit)
  ConnectionId,       // Connection identifier
  Timestamp,          // SpacetimeDB timestamp
  TimeDuration,       // Duration type
  Uuid,               // UUID type
} from 'spacetimedb';
生成的类型
// From your module_bindings
import {
  DbConnection,        // Connection class
  DbConnectionBuilder, // Builder class
  SubscriptionBuilder, // Subscription builder
  SubscriptionHandle,  // Subscription handle
  EventContext,        // Event callback context
  ReducerEventContext, // Reducer callback context
  ErrorContext,        // Error callback context
  tables,              // Table accessors for useTable
  reducers,            // Reducer definitions for useReducer
  query,               // Typed query builder

  // Your custom types
  Player,
  Point,
  // ... etc
} from './module_bindings';

命令

# Start local server
spacetime start

# Publish module
spacetime publish <module-name> --project-path <backend-dir>

# Clear database and republish
spacetime publish <module-name> --clear-database -y --project-path <backend-dir>

# Generate bindings
spacetime generate --lang typescript --out-dir <client>/src/module_bindings --project-path <backend-dir>

# View logs
spacetime logs <module-name>

最佳实践

  1. 存储身份验证令牌:保存 onConnect 中的令牌,以便无缝重新连接。

  2. 连接后订阅:在 onConnect 回调中设置订阅。

  3. 使用类型化查询:优先使用 query 构建器,而不是原始 SQL 字符串,以确保类型安全。

  4. 处理所有连接状态:实现 onConnect、onDisconnect 和 onConnectError。

  5. 高频更新时使用轻量模式:为游戏或实时应用启用 .withLightMode(true)。

  6. 完成后取消订阅:组件卸载或不再需要数据时,清理订阅。

  7. 使用主键:在表上定义主键,以启用 onUpdate 回调。

  8. 记忆化 connectionBuilder:始终使用 useMemo() 包装,以避免重新连接。

  9. 让订阅驱动状态:避免乐观更新;让服务端作为事实来源。

常见模式

重连逻辑
function createConnection(token?: string) {
  return DbConnection.builder()
    .withUri('ws://localhost:3000')
    .withModuleName('my_database')
    .withToken(token)
    .onConnect((conn, identity, newToken) => {
      localStorage.setItem('token', newToken);
      setupSubscriptions(conn);
    })
    .onDisconnect(() => {
      // Reconnect after delay
      setTimeout(() => {
        createConnection(localStorage.getItem('token') ?? undefined);
      }, 3000);
    })
    .build();
}
乐观更新
function PlayerScore({ player }) {
  const updateScore = useReducer(reducers.updateScore);
  const [optimisticScore, setOptimisticScore] = useState(player.score);

  const handleClick = () => {
    setOptimisticScore(prev => prev + 1);
    updateScore({ playerId: player.id, delta: 1 });
  };

  // Sync with actual data
  useEffect(() => {
    setOptimisticScore(player.score);
  }, [player.score]);

  return <div onClick={handleClick}>Score: {optimisticScore}</div>;
}
使用多个条件进行筛选
// Using query builder
query.player
  .where(row => row.team.eq('red'))
  .where(row => row.score.gte(100))
  .build();

// Using React hooks
const [redTeamHighScorers] = useTable(
  tables.player,
  where(eq('team', 'red')),  // Additional filtering in client
);
const filtered = redTeamHighScorers.filter(p => p.score >= 100);

项目结构

服务端(backend/spacetimedb/)
src/schema.ts   -> Tables, export spacetimedb
src/index.ts    -> Reducers, lifecycle, import schema
package.json    -> { "type": "module", "dependencies": { "spacetimedb": "^1.11.0" } }
tsconfig.json   -> Standard config
避免循环导入
schema.ts -> defines tables AND exports spacetimedb
index.ts  -> imports spacetimedb from ./schema, defines reducers
客户端(client/)
src/module_bindings/ -> Generated (spacetime generate)
src/main.tsx         -> Provider, connection setup
src/App.tsx          -> UI components
src/config.ts        -> MODULE_NAME, SPACETIMEDB_URI

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