版本：11.x

中間件

您可以使用 t.procedure.use() 方法將中間件新增至程序。中間件會包裝程序的呼叫，並且必須傳遞其回傳值。

授權

在以下範例中，任何呼叫 adminProcedure 都會確保使用者在執行前為「管理員」。

ts
import { TRPCError, initTRPC } from '@trpc/server';
 
interface Context {
  user?: {
    id: string;
    isAdmin: boolean;
    // [..]
  };
}
 
const t = initTRPC.context<Context>().create();
export const publicProcedure = t.procedure;
export const router = t.router;
 
export const adminProcedure = publicProcedure.use(async (opts) => {
  const { ctx } = opts;
  if (!ctx.user?.isAdmin) {
    throw new TRPCError({ code: 'UNAUTHORIZED' });
  }
  return opts.next({
    ctx: {
      user: ctx.user,
    },
  });
});

ts
import { TRPCError, initTRPC } from '@trpc/server';
 
interface Context {
  user?: {
    id: string;
    isAdmin: boolean;
    // [..]
  };
}
 
const t = initTRPC.context<Context>().create();
export const publicProcedure = t.procedure;
export const router = t.router;
 
export const adminProcedure = publicProcedure.use(async (opts) => {
  const { ctx } = opts;
  if (!ctx.user?.isAdmin) {
    throw new TRPCError({ code: 'UNAUTHORIZED' });
  }
  return opts.next({
    ctx: {
      user: ctx.user,
    },
  });
});

ts
import { adminProcedure, publicProcedure, router } from './trpc';
 
const adminRouter = router({
  secretPlace: adminProcedure.query(() => 'a key'),
});
 
export const appRouter = router({
  foo: publicProcedure.query(() => 'bar'),
  admin: adminRouter,
});

ts
import { adminProcedure, publicProcedure, router } from './trpc';
 
const adminRouter = router({
  secretPlace: adminProcedure.query(() => 'a key'),
});
 
export const appRouter = router({
  foo: publicProcedure.query(() => 'bar'),
  admin: adminRouter,
});

提示

請參閱錯誤處理以進一步了解上述範例中引發的 TRPCError。

記錄

在以下範例中，查詢的計時會自動記錄。

ts
export const loggedProcedure = publicProcedure.use(async (opts) => {
  const start = Date.now();
 
  const result = await opts.next();
 
  const durationMs = Date.now() - start;
  const meta = { path: opts.path, type: opts.type, durationMs };
 
  result.ok
    ? console.log('OK request timing:', meta)
    : console.error('Non-OK request timing', meta);
 
  return result;
});

ts
export const loggedProcedure = publicProcedure.use(async (opts) => {
  const start = Date.now();
 
  const result = await opts.next();
 
  const durationMs = Date.now() - start;
  const meta = { path: opts.path, type: opts.type, durationMs };
 
  result.ok
    ? console.log('OK request timing:', meta)
    : console.error('Non-OK request timing', meta);
 
  return result;
});

ts
import { loggedProcedure, router } from './trpc';
 
export const appRouter = router({
  foo: loggedProcedure.query(() => 'bar'),
  abc: loggedProcedure.query(() => 'def'),
});

ts
import { loggedProcedure, router } from './trpc';
 
export const appRouter = router({
  foo: loggedProcedure.query(() => 'bar'),
  abc: loggedProcedure.query(() => 'def'),
});

內容擴充

「內容擴充」讓中介軟體能夠以類型安全的方式動態新增和覆寫基本程序內容中的金鑰。

以下是一個中介軟體範例，它會變更內容的屬性，然後所有連鎖使用者（例如其他中介軟體和程序）都可以使用這些變更

ts
type Context = {
  // user is nullable
  user?: {
    id: string;
  };
};
 
const protectedProcedure = publicProcedure.use(async function isAuthed(opts) {
  const { ctx } = opts;
  // `ctx.user` is nullable
  if (!ctx.user) {
            (property) user: {
    id: string;
} | undefined
    throw new TRPCError({ code: 'UNAUTHORIZED' });
  }
 
  return opts.next({
    ctx: {
      // ✅ user value is known to be non-null now
      user: ctx.user,
       (property) user: {
    id: string;
}
    },
  });
});
 
protectedProcedure.query(({ ctx }) => ctx.user);
                                           (property) user: {
    id: string;
}

ts
type Context = {
  // user is nullable
  user?: {
    id: string;
  };
};
 
const protectedProcedure = publicProcedure.use(async function isAuthed(opts) {
  const { ctx } = opts;
  // `ctx.user` is nullable
  if (!ctx.user) {
            (property) user: {
    id: string;
} | undefined
    throw new TRPCError({ code: 'UNAUTHORIZED' });
  }
 
  return opts.next({
    ctx: {
      // ✅ user value is known to be non-null now
      user: ctx.user,
       (property) user: {
    id: string;
}
    },
  });
});
 
protectedProcedure.query(({ ctx }) => ctx.user);
                                           (property) user: {
    id: string;
}

使用 `.concat()` 建立可重複使用的中介軟體和外掛程式

資訊

我們將其加上前綴 unstable_，因為它是一個新的 API，但您可以放心使用！閱讀更多。

提示

使用 t.middleware 建立中介軟體的限制是 Context 類型與 tRPC 執行個體的 Context 類型相關聯。
使用 experimental_standaloneMiddleware() 建立中介軟體的限制是您無法定義與模組相關聯的輸入剖析器等。

tRPC 有個稱為 .concat() 的 API，讓您可以獨立定義部分程序，並將其用於與外掛程式內容和元資料相符的任何 tRPC 執行個體。

此輔助程式主要用於使用 tRPC 建立外掛程式和函式庫。

ts
// ------------------------------------------------
// 🧩🧩🧩 a library creating a reusable plugin 🧩🧩🧩
// @filename: myPlugin.ts
 
import { initTRPC, TRPCError } from '@trpc/server';
 
export function createMyPlugin() {
  // When creating a plugin for tRPC, you use the same API as creating any other tRPC-app
  // this is the plugin's root `t`-object
  const t = initTRPC
    .context<{
      // the procedure using the plugin will need to extend this context
    }>()
    .meta<{
      // the base `initTRPC`-object of the application using this needs to extend this meta
    }>()
    .create();
 
  return {
    // you can also add `.input()` if you want your plugin to do input validation
    pluginProc: t.procedure.use((opts) => {
      return opts.next({
        ctx: {
          fromPlugin: 'hello from myPlugin' as const,
        },
      });
    }),
  };
}
// ------------------------------------
// 🚀🚀🚀 the app using the plugin 🚀🚀🚀
// @filename: app.ts
import { createMyPlugin } from './myPlugin';
import { initTRPC, TRPCError } from '@trpc/server';
 
 
// the app's root `t`-object
const t = initTRPC
  .context<{
    // ...
  }>()
  .create();
 
 
export const publicProcedure = t.procedure;
export const router = t.router;
 
// initialize the plugin (a real-world example would likely take options here)
const plugin = createMyPlugin();
 
// create a base procedure using the plugin
const procedureWithPlugin = publicProcedure
  .unstable_concat(
    plugin.pluginProc,
  )
  .use(opts => {
    const { ctx } = opts;
            const ctx: {
    fromPlugin: "hello from myPlugin";
}
    return opts.next()
  })
 
 
export const appRouter = router({
  hello: procedureWithPlugin.query(opts => {
    return opts.ctx.fromPlugin;
  })
})

ts
// ------------------------------------------------
// 🧩🧩🧩 a library creating a reusable plugin 🧩🧩🧩
// @filename: myPlugin.ts
 
import { initTRPC, TRPCError } from '@trpc/server';
 
export function createMyPlugin() {
  // When creating a plugin for tRPC, you use the same API as creating any other tRPC-app
  // this is the plugin's root `t`-object
  const t = initTRPC
    .context<{
      // the procedure using the plugin will need to extend this context
    }>()
    .meta<{
      // the base `initTRPC`-object of the application using this needs to extend this meta
    }>()
    .create();
 
  return {
    // you can also add `.input()` if you want your plugin to do input validation
    pluginProc: t.procedure.use((opts) => {
      return opts.next({
        ctx: {
          fromPlugin: 'hello from myPlugin' as const,
        },
      });
    }),
  };
}
// ------------------------------------
// 🚀🚀🚀 the app using the plugin 🚀🚀🚀
// @filename: app.ts
import { createMyPlugin } from './myPlugin';
import { initTRPC, TRPCError } from '@trpc/server';
 
 
// the app's root `t`-object
const t = initTRPC
  .context<{
    // ...
  }>()
  .create();
 
 
export const publicProcedure = t.procedure;
export const router = t.router;
 
// initialize the plugin (a real-world example would likely take options here)
const plugin = createMyPlugin();
 
// create a base procedure using the plugin
const procedureWithPlugin = publicProcedure
  .unstable_concat(
    plugin.pluginProc,
  )
  .use(opts => {
    const { ctx } = opts;
            const ctx: {
    fromPlugin: "hello from myPlugin";
}
    return opts.next()
  })
 
 
export const appRouter = router({
  hello: procedureWithPlugin.query(opts => {
    return opts.ctx.fromPlugin;
  })
})

擴充中間件

資訊

我們將其加上前綴 unstable_，因為它是一個新的 API，但您可以放心使用！閱讀更多。

我們有一個強大的功能稱為 .pipe()，它允許您以類型安全的方式擴充中間件。

以下是一個擴充基本中間件 (foo) 的中間件範例。如同上述的內容擴充範例，串接中間件會變更內容的屬性，而程序會接收新的內容值。

ts
const fooMiddleware = t.middleware((opts) => {
  return opts.next({
    ctx: {
      foo: 'foo' as const,
    },
  });
});
 
const barMiddleware = fooMiddleware.unstable_pipe((opts) => {
  const { ctx } = opts;
  ctx.foo;
      
(property) foo: "foo"
  return opts.next({
    ctx: {
      bar: 'bar' as const,
    },
  });
});
 
const barProcedure = publicProcedure.use(barMiddleware);
barProcedure.query(({ ctx }) => ctx.bar);
                      (parameter) ctx: {
    foo: "foo";
    bar: "bar";
}

ts
const fooMiddleware = t.middleware((opts) => {
  return opts.next({
    ctx: {
      foo: 'foo' as const,
    },
  });
});
 
const barMiddleware = fooMiddleware.unstable_pipe((opts) => {
  const { ctx } = opts;
  ctx.foo;
      
(property) foo: "foo"
  return opts.next({
    ctx: {
      bar: 'bar' as const,
    },
  });
});
 
const barProcedure = publicProcedure.use(barMiddleware);
barProcedure.query(({ ctx }) => ctx.bar);
                      (parameter) ctx: {
    foo: "foo";
    bar: "bar";
}

請注意串接中間件的順序很重要，而且內容必須重疊。以下顯示一個禁止串接的範例。在此，fooMiddleware 會覆寫 ctx.a，而 barMiddleware 仍然期待 initTRPC 中初始化的根內容 - 因此串接 fooMiddleware 與 barMiddleware 會失敗，而串接 barMiddleware 與 fooMiddleware 則會成功。

ts
import { initTRPC } from '@trpc/server';
 
const t = initTRPC
  .context<{
    a: {
      b: 'a';
    };
  }>()
  .create();
 
const fooMiddleware = t.middleware((opts) => {
  const { ctx } = opts;
  ctx.a; // 👈 fooMiddleware expects `ctx.a` to be an object
     (property) a: {
    b: 'a';
}
  return opts.next({
    ctx: {
      a: 'a' as const, // 👈 `ctx.a` is no longer an object
    },
  });
});
 
const barMiddleware = t.middleware((opts) => {
  const { ctx } = opts;
  ctx.a; // 👈 barMiddleware expects `ctx.a` to be an object
     (property) a: {
    b: 'a';
}
  return opts.next({
    ctx: {
      foo: 'foo' as const,
    },
  });
});
 
// ❌ `ctx.a` does not overlap from `fooMiddleware` to `barMiddleware`
fooMiddleware.unstable_pipe(barMiddleware);
Argument of type 'MiddlewareBuilder<{ a: { b: "a"; }; }, object, { foo: "foo"; }, unknown>' is not assignable to parameter of type 'MiddlewareFunction<{ a: { b: "a"; }; }, object, { a: "a"; }, { foo: "foo"; }, unknown> | MiddlewareBuilder<{ a: "a"; }, object, { foo: "foo"; }, unknown>'.
  Type 'MiddlewareBuilder<{ a: { b: "a"; }; }, object, { foo: "foo"; }, unknown>' is not assignable to type 'MiddlewareBuilder<{ a: "a"; }, object, { foo: "foo"; }, unknown>'.
    Types of property 'unstable_pipe' are incompatible.
      Type '<$ContextOverridesOut>(fn: MiddlewareFunction<{ a: { b: "a"; }; }, object, { foo: "foo"; }, $ContextOverridesOut, unknown> | MiddlewareBuilder<{ a: { b: "a"; }; foo: "foo"; }, object, $ContextOverridesOut, unknown>) => MiddlewareBuilder<...>' is not assignable to type '<$ContextOverridesOut>(fn: MiddlewareFunction<{ a: "a"; }, object, { foo: "foo"; }, $ContextOverridesOut, unknown> | MiddlewareBuilder<{ a: "a"; foo: "foo"; }, object, $ContextOverridesOut, unknown>) => MiddlewareBuilder<...>'.
        Types of parameters 'fn' and 'fn' are incompatible.
          Type 'MiddlewareFunction<{ a: "a"; }, object, { foo: "foo"; }, any, unknown> | MiddlewareBuilder<{ a: "a"; foo: "foo"; }, object, any, unknown>' is not assignable to type 'MiddlewareFunction<{ a: { b: "a"; }; }, object, { foo: "foo"; }, any, unknown> | MiddlewareBuilder<{ a: { b: "a"; }; foo: "foo"; }, object, any, unknown>'.
            Type 'MiddlewareFunction<{ a: "a"; }, object, { foo: "foo"; }, any, unknown>' is not assignable to type 'MiddlewareFunction<{ a: { b: "a"; }; }, object, { foo: "foo"; }, any, unknown> | MiddlewareBuilder<{ a: { b: "a"; }; foo: "foo"; }, object, any, unknown>'.
              Type 'MiddlewareFunction<{ a: "a"; }, object, { foo: "foo"; }, any, unknown>' is not assignable to type 'MiddlewareFunction<{ a: { b: "a"; }; }, object, { foo: "foo"; }, any, unknown>'.
                Types of parameters 'opts' and 'opts' are incompatible.
                  Type '{ ctx: { a: { b: "a"; }; foo: "foo"; }; type: "query" | "mutation" | "subscription"; path: string; input: unknown; getRawInput: GetRawInputFn; meta: object | undefined; next: { (): Promise<MiddlewareResult<{ foo: "foo"; }>>; <$ContextOverride>(opts: { ...; }): Promise<...>; (opts: { ...; }): Promise<...>; }; }' is not assignable to type '{ ctx: { a: "a"; foo: "foo"; }; type: "query" | "mutation" | "subscription"; path: string; input: unknown; getRawInput: GetRawInputFn; meta: object | undefined; next: { (): Promise<MiddlewareResult<{ foo: "foo"; }>>; <$ContextOverride>(opts: { ...; }): Promise<...>; (opts: { ...; }): Promise<...>; }; }'.
                    The types of 'ctx.a' are incompatible between these types.
                      Type '{ b: "a"; }' is not assignable to type '"a"'.2345Argument of type 'MiddlewareBuilder<{ a: { b: "a"; }; }, object, { foo: "foo"; }, unknown>' is not assignable to parameter of type 'MiddlewareFunction<{ a: { b: "a"; }; }, object, { a: "a"; }, { foo: "foo"; }, unknown> | MiddlewareBuilder<{ a: "a"; }, object, { foo: "foo"; }, unknown>'.
  Type 'MiddlewareBuilder<{ a: { b: "a"; }; }, object, { foo: "foo"; }, unknown>' is not assignable to type 'MiddlewareBuilder<{ a: "a"; }, object, { foo: "foo"; }, unknown>'.
    Types of property 'unstable_pipe' are incompatible.
      Type '<$ContextOverridesOut>(fn: MiddlewareFunction<{ a: { b: "a"; }; }, object, { foo: "foo"; }, $ContextOverridesOut, unknown> | MiddlewareBuilder<{ a: { b: "a"; }; foo: "foo"; }, object, $ContextOverridesOut, unknown>) => MiddlewareBuilder<...>' is not assignable to type '<$ContextOverridesOut>(fn: MiddlewareFunction<{ a: "a"; }, object, { foo: "foo"; }, $ContextOverridesOut, unknown> | MiddlewareBuilder<{ a: "a"; foo: "foo"; }, object, $ContextOverridesOut, unknown>) => MiddlewareBuilder<...>'.
        Types of parameters 'fn' and 'fn' are incompatible.
          Type 'MiddlewareFunction<{ a: "a"; }, object, { foo: "foo"; }, any, unknown> | MiddlewareBuilder<{ a: "a"; foo: "foo"; }, object, any, unknown>' is not assignable to type 'MiddlewareFunction<{ a: { b: "a"; }; }, object, { foo: "foo"; }, any, unknown> | MiddlewareBuilder<{ a: { b: "a"; }; foo: "foo"; }, object, any, unknown>'.
            Type 'MiddlewareFunction<{ a: "a"; }, object, { foo: "foo"; }, any, unknown>' is not assignable to type 'MiddlewareFunction<{ a: { b: "a"; }; }, object, { foo: "foo"; }, any, unknown> | MiddlewareBuilder<{ a: { b: "a"; }; foo: "foo"; }, object, any, unknown>'.
              Type 'MiddlewareFunction<{ a: "a"; }, object, { foo: "foo"; }, any, unknown>' is not assignable to type 'MiddlewareFunction<{ a: { b: "a"; }; }, object, { foo: "foo"; }, any, unknown>'.
                Types of parameters 'opts' and 'opts' are incompatible.
                  Type '{ ctx: { a: { b: "a"; }; foo: "foo"; }; type: "query" | "mutation" | "subscription"; path: string; input: unknown; getRawInput: GetRawInputFn; meta: object | undefined; next: { (): Promise<MiddlewareResult<{ foo: "foo"; }>>; <$ContextOverride>(opts: { ...; }): Promise<...>; (opts: { ...; }): Promise<...>; }; }' is not assignable to type '{ ctx: { a: "a"; foo: "foo"; }; type: "query" | "mutation" | "subscription"; path: string; input: unknown; getRawInput: GetRawInputFn; meta: object | undefined; next: { (): Promise<MiddlewareResult<{ foo: "foo"; }>>; <$ContextOverride>(opts: { ...; }): Promise<...>; (opts: { ...; }): Promise<...>; }; }'.
                    The types of 'ctx.a' are incompatible between these types.
                      Type '{ b: "a"; }' is not assignable to type '"a"'. 
// ✅ `ctx.a` overlaps from `barMiddleware` and `fooMiddleware`
barMiddleware.unstable_pipe(fooMiddleware);

ts
import { initTRPC } from '@trpc/server';
 
const t = initTRPC
  .context<{
    a: {
      b: 'a';
    };
  }>()
  .create();
 
const fooMiddleware = t.middleware((opts) => {
  const { ctx } = opts;
  ctx.a; // 👈 fooMiddleware expects `ctx.a` to be an object
     (property) a: {
    b: 'a';
}
  return opts.next({
    ctx: {
      a: 'a' as const, // 👈 `ctx.a` is no longer an object
    },
  });
});
 
const barMiddleware = t.middleware((opts) => {
  const { ctx } = opts;
  ctx.a; // 👈 barMiddleware expects `ctx.a` to be an object
     (property) a: {
    b: 'a';
}
  return opts.next({
    ctx: {
      foo: 'foo' as const,
    },
  });
});
 
// ❌ `ctx.a` does not overlap from `fooMiddleware` to `barMiddleware`
fooMiddleware.unstable_pipe(barMiddleware);
Argument of type 'MiddlewareBuilder<{ a: { b: "a"; }; }, object, { foo: "foo"; }, unknown>' is not assignable to parameter of type 'MiddlewareFunction<{ a: { b: "a"; }; }, object, { a: "a"; }, { foo: "foo"; }, unknown> | MiddlewareBuilder<{ a: "a"; }, object, { foo: "foo"; }, unknown>'.
  Type 'MiddlewareBuilder<{ a: { b: "a"; }; }, object, { foo: "foo"; }, unknown>' is not assignable to type 'MiddlewareBuilder<{ a: "a"; }, object, { foo: "foo"; }, unknown>'.
    Types of property 'unstable_pipe' are incompatible.
      Type '<$ContextOverridesOut>(fn: MiddlewareFunction<{ a: { b: "a"; }; }, object, { foo: "foo"; }, $ContextOverridesOut, unknown> | MiddlewareBuilder<{ a: { b: "a"; }; foo: "foo"; }, object, $ContextOverridesOut, unknown>) => MiddlewareBuilder<...>' is not assignable to type '<$ContextOverridesOut>(fn: MiddlewareFunction<{ a: "a"; }, object, { foo: "foo"; }, $ContextOverridesOut, unknown> | MiddlewareBuilder<{ a: "a"; foo: "foo"; }, object, $ContextOverridesOut, unknown>) => MiddlewareBuilder<...>'.
        Types of parameters 'fn' and 'fn' are incompatible.
          Type 'MiddlewareFunction<{ a: "a"; }, object, { foo: "foo"; }, any, unknown> | MiddlewareBuilder<{ a: "a"; foo: "foo"; }, object, any, unknown>' is not assignable to type 'MiddlewareFunction<{ a: { b: "a"; }; }, object, { foo: "foo"; }, any, unknown> | MiddlewareBuilder<{ a: { b: "a"; }; foo: "foo"; }, object, any, unknown>'.
            Type 'MiddlewareFunction<{ a: "a"; }, object, { foo: "foo"; }, any, unknown>' is not assignable to type 'MiddlewareFunction<{ a: { b: "a"; }; }, object, { foo: "foo"; }, any, unknown> | MiddlewareBuilder<{ a: { b: "a"; }; foo: "foo"; }, object, any, unknown>'.
              Type 'MiddlewareFunction<{ a: "a"; }, object, { foo: "foo"; }, any, unknown>' is not assignable to type 'MiddlewareFunction<{ a: { b: "a"; }; }, object, { foo: "foo"; }, any, unknown>'.
                Types of parameters 'opts' and 'opts' are incompatible.
                  Type '{ ctx: { a: { b: "a"; }; foo: "foo"; }; type: "query" | "mutation" | "subscription"; path: string; input: unknown; getRawInput: GetRawInputFn; meta: object | undefined; next: { (): Promise<MiddlewareResult<{ foo: "foo"; }>>; <$ContextOverride>(opts: { ...; }): Promise<...>; (opts: { ...; }): Promise<...>; }; }' is not assignable to type '{ ctx: { a: "a"; foo: "foo"; }; type: "query" | "mutation" | "subscription"; path: string; input: unknown; getRawInput: GetRawInputFn; meta: object | undefined; next: { (): Promise<MiddlewareResult<{ foo: "foo"; }>>; <$ContextOverride>(opts: { ...; }): Promise<...>; (opts: { ...; }): Promise<...>; }; }'.
                    The types of 'ctx.a' are incompatible between these types.
                      Type '{ b: "a"; }' is not assignable to type '"a"'.2345Argument of type 'MiddlewareBuilder<{ a: { b: "a"; }; }, object, { foo: "foo"; }, unknown>' is not assignable to parameter of type 'MiddlewareFunction<{ a: { b: "a"; }; }, object, { a: "a"; }, { foo: "foo"; }, unknown> | MiddlewareBuilder<{ a: "a"; }, object, { foo: "foo"; }, unknown>'.
  Type 'MiddlewareBuilder<{ a: { b: "a"; }; }, object, { foo: "foo"; }, unknown>' is not assignable to type 'MiddlewareBuilder<{ a: "a"; }, object, { foo: "foo"; }, unknown>'.
    Types of property 'unstable_pipe' are incompatible.
      Type '<$ContextOverridesOut>(fn: MiddlewareFunction<{ a: { b: "a"; }; }, object, { foo: "foo"; }, $ContextOverridesOut, unknown> | MiddlewareBuilder<{ a: { b: "a"; }; foo: "foo"; }, object, $ContextOverridesOut, unknown>) => MiddlewareBuilder<...>' is not assignable to type '<$ContextOverridesOut>(fn: MiddlewareFunction<{ a: "a"; }, object, { foo: "foo"; }, $ContextOverridesOut, unknown> | MiddlewareBuilder<{ a: "a"; foo: "foo"; }, object, $ContextOverridesOut, unknown>) => MiddlewareBuilder<...>'.
        Types of parameters 'fn' and 'fn' are incompatible.
          Type 'MiddlewareFunction<{ a: "a"; }, object, { foo: "foo"; }, any, unknown> | MiddlewareBuilder<{ a: "a"; foo: "foo"; }, object, any, unknown>' is not assignable to type 'MiddlewareFunction<{ a: { b: "a"; }; }, object, { foo: "foo"; }, any, unknown> | MiddlewareBuilder<{ a: { b: "a"; }; foo: "foo"; }, object, any, unknown>'.
            Type 'MiddlewareFunction<{ a: "a"; }, object, { foo: "foo"; }, any, unknown>' is not assignable to type 'MiddlewareFunction<{ a: { b: "a"; }; }, object, { foo: "foo"; }, any, unknown> | MiddlewareBuilder<{ a: { b: "a"; }; foo: "foo"; }, object, any, unknown>'.
              Type 'MiddlewareFunction<{ a: "a"; }, object, { foo: "foo"; }, any, unknown>' is not assignable to type 'MiddlewareFunction<{ a: { b: "a"; }; }, object, { foo: "foo"; }, any, unknown>'.
                Types of parameters 'opts' and 'opts' are incompatible.
                  Type '{ ctx: { a: { b: "a"; }; foo: "foo"; }; type: "query" | "mutation" | "subscription"; path: string; input: unknown; getRawInput: GetRawInputFn; meta: object | undefined; next: { (): Promise<MiddlewareResult<{ foo: "foo"; }>>; <$ContextOverride>(opts: { ...; }): Promise<...>; (opts: { ...; }): Promise<...>; }; }' is not assignable to type '{ ctx: { a: "a"; foo: "foo"; }; type: "query" | "mutation" | "subscription"; path: string; input: unknown; getRawInput: GetRawInputFn; meta: object | undefined; next: { (): Promise<MiddlewareResult<{ foo: "foo"; }>>; <$ContextOverride>(opts: { ...; }): Promise<...>; (opts: { ...; }): Promise<...>; }; }'.
                    The types of 'ctx.a' are incompatible between these types.
                      Type '{ b: "a"; }' is not assignable to type '"a"'. 
// ✅ `ctx.a` overlaps from `barMiddleware` and `fooMiddleware`
barMiddleware.unstable_pipe(fooMiddleware);

實驗性：獨立中間件

資訊

這已被棄用，建議使用 .unstable_concat()

tRPC 有個實驗性 API 稱為 experimental_standaloneMiddleware，它允許您獨立定義一個中間件，可與任何 tRPC 執行個體一起使用。使用 t.middleware 建立中間件時，有一個限制是 Context 類型與 tRPC 執行個體的 Context 類型綁定在一起。這表示您無法將同一個中間件與有多個 Context 類型的 tRPC 執行個體一起使用。

使用 experimental_standaloneMiddleware，您可以建立一個明確定義其需求的中間件，也就是 Context、Input 和 Meta 類型

ts
import {
  experimental_standaloneMiddleware,
  initTRPC,
  TRPCError,
} from '@trpc/server';
import * as z from 'zod';
 
const projectAccessMiddleware = experimental_standaloneMiddleware<{
  ctx: { allowedProjects: string[] }; // defaults to 'object' if not defined
  input: { projectId: string }; // defaults to 'unknown' if not defined
  // 'meta', not defined here, defaults to 'object | undefined'
}>().create((opts) => {
  if (!opts.ctx.allowedProjects.includes(opts.input.projectId)) {
    throw new TRPCError({
      code: 'FORBIDDEN',
      message: 'Not allowed',
    });
  }
 
  return opts.next();
});
 
const t1 = initTRPC
  .context<{
    allowedProjects: string[];
  }>()
  .create();
 
// ✅ `ctx.allowedProjects` satisfies "string[]" and `input.projectId` satisfies "string"
const accessControlledProcedure = t1.procedure
  .input(z.object({ projectId: z.string() }))
  .use(projectAccessMiddleware);
 
// ❌ `ctx.allowedProjects` satisfies "string[]" but `input.projectId` does not satisfy "string"
const accessControlledProcedure2 = t1.procedure
  .input(z.object({ projectId: z.number() }))
  .use(projectAccessMiddleware);
Argument of type 'MiddlewareBuilder<{ allowedProjects: string[]; }, object, object, { projectId: string; }>' is not assignable to parameter of type 'MiddlewareBuilder<{ allowedProjects: string[]; }, object, object, { projectId: number; }> | MiddlewareFunction<{ allowedProjects: string[]; }, object, object, object, { projectId: number; }>'.
  Type 'MiddlewareBuilder<{ allowedProjects: string[]; }, object, object, { projectId: string; }>' is not assignable to type 'MiddlewareBuilder<{ allowedProjects: string[]; }, object, object, { projectId: number; }>'.
    Types of property 'unstable_pipe' are incompatible.
      Type '<$ContextOverridesOut>(fn: MiddlewareFunction<{ allowedProjects: string[]; }, object, object, $ContextOverridesOut, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, $ContextOverridesOut, { ...; }>) => MiddlewareBuilder<...>' is not assignable to type '<$ContextOverridesOut>(fn: MiddlewareFunction<{ allowedProjects: string[]; }, object, object, $ContextOverridesOut, { projectId: number; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, $ContextOverridesOut, { ...; }>) => MiddlewareBuilder<...>'.
        Types of parameters 'fn' and 'fn' are incompatible.
          Type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: number; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, any, { projectId: number; }>' is not assignable to type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, any, { projectId: string; }>'.
            Type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: number; }>' is not assignable to type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, any, { projectId: string; }>'.
              Type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: number; }>' is not assignable to type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: string; }>'.
                Types of parameters 'opts' and 'opts' are incompatible.
                  Type '{ ctx: { allowedProjects: string[]; }; type: "query" | "mutation" | "subscription"; path: string; input: { projectId: string; }; getRawInput: GetRawInputFn; meta: object | undefined; next: { ...; }; }' is not assignable to type '{ ctx: { allowedProjects: string[]; }; type: "query" | "mutation" | "subscription"; path: string; input: { projectId: number; }; getRawInput: GetRawInputFn; meta: object | undefined; next: { ...; }; }'.
                    Types of property 'input' are incompatible.
                      Type '{ projectId: string; }' is not assignable to type '{ projectId: number; }'.2345Argument of type 'MiddlewareBuilder<{ allowedProjects: string[]; }, object, object, { projectId: string; }>' is not assignable to parameter of type 'MiddlewareBuilder<{ allowedProjects: string[]; }, object, object, { projectId: number; }> | MiddlewareFunction<{ allowedProjects: string[]; }, object, object, object, { projectId: number; }>'.
  Type 'MiddlewareBuilder<{ allowedProjects: string[]; }, object, object, { projectId: string; }>' is not assignable to type 'MiddlewareBuilder<{ allowedProjects: string[]; }, object, object, { projectId: number; }>'.
    Types of property 'unstable_pipe' are incompatible.
      Type '<$ContextOverridesOut>(fn: MiddlewareFunction<{ allowedProjects: string[]; }, object, object, $ContextOverridesOut, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, $ContextOverridesOut, { ...; }>) => MiddlewareBuilder<...>' is not assignable to type '<$ContextOverridesOut>(fn: MiddlewareFunction<{ allowedProjects: string[]; }, object, object, $ContextOverridesOut, { projectId: number; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, $ContextOverridesOut, { ...; }>) => MiddlewareBuilder<...>'.
        Types of parameters 'fn' and 'fn' are incompatible.
          Type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: number; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, any, { projectId: number; }>' is not assignable to type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, any, { projectId: string; }>'.
            Type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: number; }>' is not assignable to type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, any, { projectId: string; }>'.
              Type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: number; }>' is not assignable to type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: string; }>'.
                Types of parameters 'opts' and 'opts' are incompatible.
                  Type '{ ctx: { allowedProjects: string[]; }; type: "query" | "mutation" | "subscription"; path: string; input: { projectId: string; }; getRawInput: GetRawInputFn; meta: object | undefined; next: { ...; }; }' is not assignable to type '{ ctx: { allowedProjects: string[]; }; type: "query" | "mutation" | "subscription"; path: string; input: { projectId: number; }; getRawInput: GetRawInputFn; meta: object | undefined; next: { ...; }; }'.
                    Types of property 'input' are incompatible.
                      Type '{ projectId: string; }' is not assignable to type '{ projectId: number; }'. 
// ❌ `ctx.allowedProjects` does not satisfy "string[]" even though `input.projectId` satisfies "string"
const t2 = initTRPC
  .context<{
    allowedProjects: number[];
  }>()
  .create();
 
const accessControlledProcedure3 = t2.procedure
  .input(z.object({ projectId: z.string() }))
  .use(projectAccessMiddleware);
Argument of type 'MiddlewareBuilder<{ allowedProjects: string[]; }, object, object, { projectId: string; }>' is not assignable to parameter of type 'MiddlewareBuilder<{ allowedProjects: number[]; }, object, object, { projectId: string; }> | MiddlewareFunction<{ allowedProjects: number[]; }, object, object, object, { projectId: string; }>'.
  Type 'MiddlewareBuilder<{ allowedProjects: string[]; }, object, object, { projectId: string; }>' is not assignable to type 'MiddlewareBuilder<{ allowedProjects: number[]; }, object, object, { projectId: string; }>'.
    Types of property 'unstable_pipe' are incompatible.
      Type '<$ContextOverridesOut>(fn: MiddlewareFunction<{ allowedProjects: string[]; }, object, object, $ContextOverridesOut, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, $ContextOverridesOut, { ...; }>) => MiddlewareBuilder<...>' is not assignable to type '<$ContextOverridesOut>(fn: MiddlewareFunction<{ allowedProjects: number[]; }, object, object, $ContextOverridesOut, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: number[]; }, object, $ContextOverridesOut, { ...; }>) => MiddlewareBuilder<...>'.
        Types of parameters 'fn' and 'fn' are incompatible.
          Type 'MiddlewareFunction<{ allowedProjects: number[]; }, object, object, any, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: number[]; }, object, any, { projectId: string; }>' is not assignable to type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, any, { projectId: string; }>'.
            Type 'MiddlewareFunction<{ allowedProjects: number[]; }, object, object, any, { projectId: string; }>' is not assignable to type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, any, { projectId: string; }>'.
              Type 'MiddlewareFunction<{ allowedProjects: number[]; }, object, object, any, { projectId: string; }>' is not assignable to type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: string; }>'.
                Types of parameters 'opts' and 'opts' are incompatible.
                  Type '{ ctx: { allowedProjects: string[]; }; type: "query" | "mutation" | "subscription"; path: string; input: { projectId: string; }; getRawInput: GetRawInputFn; meta: object | undefined; next: { ...; }; }' is not assignable to type '{ ctx: { allowedProjects: number[]; }; type: "query" | "mutation" | "subscription"; path: string; input: { projectId: string; }; getRawInput: GetRawInputFn; meta: object | undefined; next: { ...; }; }'.
                    The types of 'ctx.allowedProjects' are incompatible between these types.
                      Type 'string[]' is not assignable to type 'number[]'.2345Argument of type 'MiddlewareBuilder<{ allowedProjects: string[]; }, object, object, { projectId: string; }>' is not assignable to parameter of type 'MiddlewareBuilder<{ allowedProjects: number[]; }, object, object, { projectId: string; }> | MiddlewareFunction<{ allowedProjects: number[]; }, object, object, object, { projectId: string; }>'.
  Type 'MiddlewareBuilder<{ allowedProjects: string[]; }, object, object, { projectId: string; }>' is not assignable to type 'MiddlewareBuilder<{ allowedProjects: number[]; }, object, object, { projectId: string; }>'.
    Types of property 'unstable_pipe' are incompatible.
      Type '<$ContextOverridesOut>(fn: MiddlewareFunction<{ allowedProjects: string[]; }, object, object, $ContextOverridesOut, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, $ContextOverridesOut, { ...; }>) => MiddlewareBuilder<...>' is not assignable to type '<$ContextOverridesOut>(fn: MiddlewareFunction<{ allowedProjects: number[]; }, object, object, $ContextOverridesOut, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: number[]; }, object, $ContextOverridesOut, { ...; }>) => MiddlewareBuilder<...>'.
        Types of parameters 'fn' and 'fn' are incompatible.
          Type 'MiddlewareFunction<{ allowedProjects: number[]; }, object, object, any, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: number[]; }, object, any, { projectId: string; }>' is not assignable to type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, any, { projectId: string; }>'.
            Type 'MiddlewareFunction<{ allowedProjects: number[]; }, object, object, any, { projectId: string; }>' is not assignable to type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, any, { projectId: string; }>'.
              Type 'MiddlewareFunction<{ allowedProjects: number[]; }, object, object, any, { projectId: string; }>' is not assignable to type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: string; }>'.
                Types of parameters 'opts' and 'opts' are incompatible.
                  Type '{ ctx: { allowedProjects: string[]; }; type: "query" | "mutation" | "subscription"; path: string; input: { projectId: string; }; getRawInput: GetRawInputFn; meta: object | undefined; next: { ...; }; }' is not assignable to type '{ ctx: { allowedProjects: number[]; }; type: "query" | "mutation" | "subscription"; path: string; input: { projectId: string; }; getRawInput: GetRawInputFn; meta: object | undefined; next: { ...; }; }'.
                    The types of 'ctx.allowedProjects' are incompatible between these types.
                      Type 'string[]' is not assignable to type 'number[]'.

ts
import {
  experimental_standaloneMiddleware,
  initTRPC,
  TRPCError,
} from '@trpc/server';
import * as z from 'zod';
 
const projectAccessMiddleware = experimental_standaloneMiddleware<{
  ctx: { allowedProjects: string[] }; // defaults to 'object' if not defined
  input: { projectId: string }; // defaults to 'unknown' if not defined
  // 'meta', not defined here, defaults to 'object | undefined'
}>().create((opts) => {
  if (!opts.ctx.allowedProjects.includes(opts.input.projectId)) {
    throw new TRPCError({
      code: 'FORBIDDEN',
      message: 'Not allowed',
    });
  }
 
  return opts.next();
});
 
const t1 = initTRPC
  .context<{
    allowedProjects: string[];
  }>()
  .create();
 
// ✅ `ctx.allowedProjects` satisfies "string[]" and `input.projectId` satisfies "string"
const accessControlledProcedure = t1.procedure
  .input(z.object({ projectId: z.string() }))
  .use(projectAccessMiddleware);
 
// ❌ `ctx.allowedProjects` satisfies "string[]" but `input.projectId` does not satisfy "string"
const accessControlledProcedure2 = t1.procedure
  .input(z.object({ projectId: z.number() }))
  .use(projectAccessMiddleware);
Argument of type 'MiddlewareBuilder<{ allowedProjects: string[]; }, object, object, { projectId: string; }>' is not assignable to parameter of type 'MiddlewareBuilder<{ allowedProjects: string[]; }, object, object, { projectId: number; }> | MiddlewareFunction<{ allowedProjects: string[]; }, object, object, object, { projectId: number; }>'.
  Type 'MiddlewareBuilder<{ allowedProjects: string[]; }, object, object, { projectId: string; }>' is not assignable to type 'MiddlewareBuilder<{ allowedProjects: string[]; }, object, object, { projectId: number; }>'.
    Types of property 'unstable_pipe' are incompatible.
      Type '<$ContextOverridesOut>(fn: MiddlewareFunction<{ allowedProjects: string[]; }, object, object, $ContextOverridesOut, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, $ContextOverridesOut, { ...; }>) => MiddlewareBuilder<...>' is not assignable to type '<$ContextOverridesOut>(fn: MiddlewareFunction<{ allowedProjects: string[]; }, object, object, $ContextOverridesOut, { projectId: number; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, $ContextOverridesOut, { ...; }>) => MiddlewareBuilder<...>'.
        Types of parameters 'fn' and 'fn' are incompatible.
          Type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: number; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, any, { projectId: number; }>' is not assignable to type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, any, { projectId: string; }>'.
            Type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: number; }>' is not assignable to type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, any, { projectId: string; }>'.
              Type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: number; }>' is not assignable to type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: string; }>'.
                Types of parameters 'opts' and 'opts' are incompatible.
                  Type '{ ctx: { allowedProjects: string[]; }; type: "query" | "mutation" | "subscription"; path: string; input: { projectId: string; }; getRawInput: GetRawInputFn; meta: object | undefined; next: { ...; }; }' is not assignable to type '{ ctx: { allowedProjects: string[]; }; type: "query" | "mutation" | "subscription"; path: string; input: { projectId: number; }; getRawInput: GetRawInputFn; meta: object | undefined; next: { ...; }; }'.
                    Types of property 'input' are incompatible.
                      Type '{ projectId: string; }' is not assignable to type '{ projectId: number; }'.2345Argument of type 'MiddlewareBuilder<{ allowedProjects: string[]; }, object, object, { projectId: string; }>' is not assignable to parameter of type 'MiddlewareBuilder<{ allowedProjects: string[]; }, object, object, { projectId: number; }> | MiddlewareFunction<{ allowedProjects: string[]; }, object, object, object, { projectId: number; }>'.
  Type 'MiddlewareBuilder<{ allowedProjects: string[]; }, object, object, { projectId: string; }>' is not assignable to type 'MiddlewareBuilder<{ allowedProjects: string[]; }, object, object, { projectId: number; }>'.
    Types of property 'unstable_pipe' are incompatible.
      Type '<$ContextOverridesOut>(fn: MiddlewareFunction<{ allowedProjects: string[]; }, object, object, $ContextOverridesOut, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, $ContextOverridesOut, { ...; }>) => MiddlewareBuilder<...>' is not assignable to type '<$ContextOverridesOut>(fn: MiddlewareFunction<{ allowedProjects: string[]; }, object, object, $ContextOverridesOut, { projectId: number; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, $ContextOverridesOut, { ...; }>) => MiddlewareBuilder<...>'.
        Types of parameters 'fn' and 'fn' are incompatible.
          Type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: number; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, any, { projectId: number; }>' is not assignable to type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, any, { projectId: string; }>'.
            Type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: number; }>' is not assignable to type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, any, { projectId: string; }>'.
              Type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: number; }>' is not assignable to type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: string; }>'.
                Types of parameters 'opts' and 'opts' are incompatible.
                  Type '{ ctx: { allowedProjects: string[]; }; type: "query" | "mutation" | "subscription"; path: string; input: { projectId: string; }; getRawInput: GetRawInputFn; meta: object | undefined; next: { ...; }; }' is not assignable to type '{ ctx: { allowedProjects: string[]; }; type: "query" | "mutation" | "subscription"; path: string; input: { projectId: number; }; getRawInput: GetRawInputFn; meta: object | undefined; next: { ...; }; }'.
                    Types of property 'input' are incompatible.
                      Type '{ projectId: string; }' is not assignable to type '{ projectId: number; }'. 
// ❌ `ctx.allowedProjects` does not satisfy "string[]" even though `input.projectId` satisfies "string"
const t2 = initTRPC
  .context<{
    allowedProjects: number[];
  }>()
  .create();
 
const accessControlledProcedure3 = t2.procedure
  .input(z.object({ projectId: z.string() }))
  .use(projectAccessMiddleware);
Argument of type 'MiddlewareBuilder<{ allowedProjects: string[]; }, object, object, { projectId: string; }>' is not assignable to parameter of type 'MiddlewareBuilder<{ allowedProjects: number[]; }, object, object, { projectId: string; }> | MiddlewareFunction<{ allowedProjects: number[]; }, object, object, object, { projectId: string; }>'.
  Type 'MiddlewareBuilder<{ allowedProjects: string[]; }, object, object, { projectId: string; }>' is not assignable to type 'MiddlewareBuilder<{ allowedProjects: number[]; }, object, object, { projectId: string; }>'.
    Types of property 'unstable_pipe' are incompatible.
      Type '<$ContextOverridesOut>(fn: MiddlewareFunction<{ allowedProjects: string[]; }, object, object, $ContextOverridesOut, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, $ContextOverridesOut, { ...; }>) => MiddlewareBuilder<...>' is not assignable to type '<$ContextOverridesOut>(fn: MiddlewareFunction<{ allowedProjects: number[]; }, object, object, $ContextOverridesOut, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: number[]; }, object, $ContextOverridesOut, { ...; }>) => MiddlewareBuilder<...>'.
        Types of parameters 'fn' and 'fn' are incompatible.
          Type 'MiddlewareFunction<{ allowedProjects: number[]; }, object, object, any, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: number[]; }, object, any, { projectId: string; }>' is not assignable to type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, any, { projectId: string; }>'.
            Type 'MiddlewareFunction<{ allowedProjects: number[]; }, object, object, any, { projectId: string; }>' is not assignable to type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, any, { projectId: string; }>'.
              Type 'MiddlewareFunction<{ allowedProjects: number[]; }, object, object, any, { projectId: string; }>' is not assignable to type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: string; }>'.
                Types of parameters 'opts' and 'opts' are incompatible.
                  Type '{ ctx: { allowedProjects: string[]; }; type: "query" | "mutation" | "subscription"; path: string; input: { projectId: string; }; getRawInput: GetRawInputFn; meta: object | undefined; next: { ...; }; }' is not assignable to type '{ ctx: { allowedProjects: number[]; }; type: "query" | "mutation" | "subscription"; path: string; input: { projectId: string; }; getRawInput: GetRawInputFn; meta: object | undefined; next: { ...; }; }'.
                    The types of 'ctx.allowedProjects' are incompatible between these types.
                      Type 'string[]' is not assignable to type 'number[]'.2345Argument of type 'MiddlewareBuilder<{ allowedProjects: string[]; }, object, object, { projectId: string; }>' is not assignable to parameter of type 'MiddlewareBuilder<{ allowedProjects: number[]; }, object, object, { projectId: string; }> | MiddlewareFunction<{ allowedProjects: number[]; }, object, object, object, { projectId: string; }>'.
  Type 'MiddlewareBuilder<{ allowedProjects: string[]; }, object, object, { projectId: string; }>' is not assignable to type 'MiddlewareBuilder<{ allowedProjects: number[]; }, object, object, { projectId: string; }>'.
    Types of property 'unstable_pipe' are incompatible.
      Type '<$ContextOverridesOut>(fn: MiddlewareFunction<{ allowedProjects: string[]; }, object, object, $ContextOverridesOut, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, $ContextOverridesOut, { ...; }>) => MiddlewareBuilder<...>' is not assignable to type '<$ContextOverridesOut>(fn: MiddlewareFunction<{ allowedProjects: number[]; }, object, object, $ContextOverridesOut, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: number[]; }, object, $ContextOverridesOut, { ...; }>) => MiddlewareBuilder<...>'.
        Types of parameters 'fn' and 'fn' are incompatible.
          Type 'MiddlewareFunction<{ allowedProjects: number[]; }, object, object, any, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: number[]; }, object, any, { projectId: string; }>' is not assignable to type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, any, { projectId: string; }>'.
            Type 'MiddlewareFunction<{ allowedProjects: number[]; }, object, object, any, { projectId: string; }>' is not assignable to type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: string; }> | MiddlewareBuilder<{ allowedProjects: string[]; }, object, any, { projectId: string; }>'.
              Type 'MiddlewareFunction<{ allowedProjects: number[]; }, object, object, any, { projectId: string; }>' is not assignable to type 'MiddlewareFunction<{ allowedProjects: string[]; }, object, object, any, { projectId: string; }>'.
                Types of parameters 'opts' and 'opts' are incompatible.
                  Type '{ ctx: { allowedProjects: string[]; }; type: "query" | "mutation" | "subscription"; path: string; input: { projectId: string; }; getRawInput: GetRawInputFn; meta: object | undefined; next: { ...; }; }' is not assignable to type '{ ctx: { allowedProjects: number[]; }; type: "query" | "mutation" | "subscription"; path: string; input: { projectId: string; }; getRawInput: GetRawInputFn; meta: object | undefined; next: { ...; }; }'.
                    The types of 'ctx.allowedProjects' are incompatible between these types.
                      Type 'string[]' is not assignable to type 'number[]'.

以下是包含多個獨立中間件的範例

ts
import { experimental_standaloneMiddleware, initTRPC } from '@trpc/server';
import * as z from 'zod';
 
const t = initTRPC.create();
const schemaA = z.object({ valueA: z.string() });
const schemaB = z.object({ valueB: z.string() });
 
const valueAUppercaserMiddleware = experimental_standaloneMiddleware<{
  input: z.infer<typeof schemaA>;
}>().create((opts) => {
  return opts.next({
    ctx: { valueAUppercase: opts.input.valueA.toUpperCase() },
  });
});
 
const valueBUppercaserMiddleware = experimental_standaloneMiddleware<{
  input: z.infer<typeof schemaB>;
}>().create((opts) => {
  return opts.next({
    ctx: { valueBUppercase: opts.input.valueB.toUpperCase() },
  });
});
 
const combinedInputThatSatisfiesBothMiddlewares = z.object({
  valueA: z.string(),
  valueB: z.string(),
  extraProp: z.string(),
});
 
t.procedure
  .input(combinedInputThatSatisfiesBothMiddlewares)
  .use(valueAUppercaserMiddleware)
  .use(valueBUppercaserMiddleware)
  .query(
    ({
      input: { valueA, valueB, extraProp },
      ctx: { valueAUppercase, valueBUppercase },
    }) =>
      `valueA: ${valueA}, valueB: ${valueB}, extraProp: ${extraProp}, valueAUppercase: ${valueAUppercase}, valueBUppercase: ${valueBUppercase}`,
  );

ts
import { experimental_standaloneMiddleware, initTRPC } from '@trpc/server';
import * as z from 'zod';
 
const t = initTRPC.create();
const schemaA = z.object({ valueA: z.string() });
const schemaB = z.object({ valueB: z.string() });
 
const valueAUppercaserMiddleware = experimental_standaloneMiddleware<{
  input: z.infer<typeof schemaA>;
}>().create((opts) => {
  return opts.next({
    ctx: { valueAUppercase: opts.input.valueA.toUpperCase() },
  });
});
 
const valueBUppercaserMiddleware = experimental_standaloneMiddleware<{
  input: z.infer<typeof schemaB>;
}>().create((opts) => {
  return opts.next({
    ctx: { valueBUppercase: opts.input.valueB.toUpperCase() },
  });
});
 
const combinedInputThatSatisfiesBothMiddlewares = z.object({
  valueA: z.string(),
  valueB: z.string(),
  extraProp: z.string(),
});
 
t.procedure
  .input(combinedInputThatSatisfiesBothMiddlewares)
  .use(valueAUppercaserMiddleware)
  .use(valueBUppercaserMiddleware)
  .query(
    ({
      input: { valueA, valueB, extraProp },
      ctx: { valueAUppercase, valueBUppercase },
    }) =>
      `valueA: ${valueA}, valueB: ${valueB}, extraProp: ${extraProp}, valueAUppercase: ${valueAUppercase}, valueBUppercase: ${valueBUppercase}`,
  );

授權​

記錄​

內容擴充​

使用 .concat() 建立可重複使用的中介軟體和外掛程式​

擴充中間件​

實驗性：獨立中間件​

授權

記錄

內容擴充

使用 `.concat()` 建立可重複使用的中介軟體和外掛程式

擴充中間件

實驗性：獨立中間件