var callbacks []*callback
	removedMap := map[string]bool{}
	for _, callback := range p.callbacks {
		if callback.match == nil || callback.match(p.db) {
			callbacks = append(callbacks, callback)
		}
		if callback.remove {
			removedMap[callback.name] = true
		}
	}

	if len(removedMap) > 0 {
		callbacks = removeCallbacks(callbacks, removedMap)
	}
	p.callbacks = callbacks

			callbacks: []callback{{h: c1}, {h: c2, before: "c4", after: "c5"}, {h: c3, before: "c4", after: "*"}, {h: c4, after: "*"}, {h: c5, before: "*"}},
			results:   []string{"c5", "c1", "c2", "c3", "c4"},
		},
	}

	for idx, data := range datas {
		db, err := gorm.Open(nil, nil)
		if err != nil {
			t.Fatal(err)
		}
		callbacks := db.Callback()

		for _, c := range data.callbacks {
			var v interface{} = callbacks.Create()

### Einen Callback-`APIRouter` erstellen

Erstellen Sie zunächst einen neuen `APIRouter`, der einen oder mehrere Callbacks enthält.

```Python hl_lines="3  25"
{!../../../docs_src/openapi_callbacks/tutorial001.py!}
```

### Die Callback-*Pfadoperation* erstellen

⚫️ 🔜 ✔️ *➡ 🛠️* 👈 🔜 📨 `Invoice` 💪, & 🔢 🔢 `callback_url` 👈 🔜 🔌 📛 ⏲.

👉 🍕 📶 😐, 🌅 📟 🎲 ⏪ 😰 👆:

```Python hl_lines="9-13  36-53"
{!../../../docs_src/openapi_callbacks/tutorial001.py!}
```

!!! tip
     `callback_url` 🔢 🔢 ⚙️ Pydantic <a href="https://docs.pydantic.dev/latest/concepts/types/#urls" class="external-link" target="_blank">📛</a> 🆎.

🕴 🆕 👜 `callbacks=messages_callback_router.routes` ❌ *➡ 🛠️ 👨‍🎨*. 👥 🔜 👀 ⚫️❔ 👈 ⏭.

Now use the parameter `callbacks` in *your API's path operation decorator* to pass the attribute `.routes` (that's actually just a `list` of routes/*path operations*) from that callback router:

```Python hl_lines="35"
{!../../../docs_src/openapi_callbacks/tutorial001.py!}
```

!!! tip

### 添加回调路由

至此，在上文创建的回调路由里就包含了*回调路径操作*（外部开发者要在外部 API 中实现）。

现在使用 API *路径操作装饰器*的参数 `callbacks`，从回调路由传递属性 `.routes`（实际上只是路由/路径操作的**列表**）：

```Python hl_lines="36"
{!../../../docs_src/openapi_callbacks/tutorial001.py!}
```

!!! tip "提示"

    注意，不能把路由本身（`invoices_callback_router`）传递给 `callback=`，要传递 `invoices_callback_router.routes` 中的 `.routes` 属性。

### 查看文档

                        },
                        "callbacks": {
                            "event_callback": {
                                "{$callback_url}/events/{$request.body.title}": {
                                    "get": {
                                        "summary": "Event Callback",
                                        "operationId": "event_callback__callback_url__events___request_body_title__get",

callback_router3 = APIRouter()


@callback_router3.get("/")
async def callback3(level3: str):
    pass  # pragma: nocover


callback_router4 = APIRouter()


@callback_router4.get("/")
async def callback4(level4: str):
    pass  # pragma: nocover


callback_router5 = APIRouter()


@callback_router5.get("/")
async def callback5(level5: str):
    pass  # pragma: nocover

      |
      """.trimMargin(),
    )
    assertThat(callbacks).isEmpty()
  }

  private fun consumeEvents(source: String) {
    val callback: ServerSentEventReader.Callback =
      object : ServerSentEventReader.Callback {
        override fun onEvent(
          id: String?,
          type: String?,
          data: String,
        ) {
          callbacks.add(Event(id, type, data))
        }

	return tx
}

// Update updates column with value using callbacks. Reference: https://gorm.io/docs/update.html#Update-Changed-Fields
func (db *DB) Update(column string, value interface{}) (tx *DB) {
	tx = db.getInstance()
	tx.Statement.Dest = map[string]interface{}{column: value}
	return tx.callbacks.Update().Execute(tx)
}