// External code calls into callbackasm at an offset corresponding
// to the callback index. Callbackasm is a table of MOV and B instructions.
// The MOV instruction loads R12 with the callback index, and the
// B instruction branches to callbackasm1.
// callbackasm1 takes the callback index from R12 and
// indexes into an array that stores information about each callback.

	JMP	sigtramp<>(SB)

TEXT runtime·callbackasm1(SB),NOSPLIT,$0
	MOVL	0(SP), AX	// will use to find our callback context

	// remove return address from stack, we are not returning to callbackasm, but to its caller.
	ADDL	$4, SP

	// address to callback parameters into CX
	LEAL	4(SP), CX

	// save registers as required for windows callback
	PUSHL	DI
	PUSHL	SI
	PUSHL	BP
	PUSHL	BX

	MOVQ	CX, (16+0)(SP)
	MOVQ	DX, (16+8)(SP)
	MOVQ	R8, (16+16)(SP)
	MOVQ	R9, (16+24)(SP)
	// R8 = address of args vector
	LEAQ	(16+0)(SP), R8

	// remove return address from stack, we are not returning to callbackasm, but to its caller.
	MOVQ	0(SP), AX
	ADDQ	$8, SP

	// determine index into runtime·cbs table
	MOVQ	$runtime·callbackasm(SB), DX
	SUBQ	DX, AX
	MOVQ	$0, DX

func (p *processor) compile() (err error) {
	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

package callbacks

import (
	"gorm.io/gorm"
)

var (
	createClauses = []string{"INSERT", "VALUES", "ON CONFLICT"}
	queryClauses  = []string{"SELECT", "FROM", "WHERE", "GROUP BY", "ORDER BY", "LIMIT", "FOR"}
	updateClauses = []string{"UPDATE", "SET", "WHERE"}
	deleteClauses = []string{"DELETE", "FROM", "WHERE"}
)

type Config struct {
	LastInsertIDReversed bool
	CreateClauses        []string
	QueryClauses         []string

// compiled with gcc via crosscall2.

// The declaration of crosscall2 is:
//   void crosscall2(void (*fn)(void *), void *, int);
//
// We need to export the symbol crosscall2 in order to support
// callbacks from shared libraries. This applies regardless of
// linking mode.
//
// Compatibility note: SWIG uses crosscall2 in exactly one situation:
// to call _cgo_panic using the pattern shown below. We need to keep

Das einzig Neue ist `callbacks=invoices_callback_router.routes` als Argument für den *Pfadoperation-Dekorator*. Wir werden als Nächstes sehen, was das ist.

## Dokumentation des Callbacks

Der tatsächliche Callback-Code hängt stark von Ihrer eigenen API-Anwendung ab.

You will see your docs including a "Callbacks" section for your *path operation* that shows how the *external API* should look like:

{!../../../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` ❌ *➡ 🛠️ 👨‍🎨*. 👥 🔜 👀 ⚫️❔ 👈 ⏭.

## 🔬 ⏲

☑ ⏲ 📟 🔜 🪀 🙇 🔛 👆 👍 🛠️ 📱.

&amp; ⚫️ 🔜 🎲 🪀 📚 ⚪️➡️ 1️⃣ 📱 ⏭.

⚫️ 💪 1️⃣ ⚖️ 2️⃣ ⏸ 📟, 💖:

```Python

```

!!! tip "提示"

    `callback_url` 查询参数使用 Pydantic 的 <a href="https://pydantic-docs.helpmanual.io/usage/types/#urls" class="external-link" target="_blank">URL</a> 类型。

此处唯一比较新的内容是*路径操作装饰器*中的 `callbacks=invoices_callback_router.routes` 参数，下文介绍。

## 存档回调

实际的回调代码高度依赖于您自己的 API 应用。

并且可能每个应用都各不相同。

回调代码可能只有一两行，比如：

```Python
callback_url = "https://example.com/api/v1/invoices/events/"