// error returned when temporary account is not found
var errNoSuchTempAccount = errors.New("Specified temporary account does not exist")

// error returned in IAM subsystem when an account doesn't exist.
var errNoSuchAccount = errors.New("Specified account does not exist")

// error returned in IAM subsystem when groups doesn't exist.

			<h2>
				<la:message key="labels.error_title" />
			</h2>
			<div>
				<la:info id="msg" message="true">
					<div class="alert alert-info">${msg}</div>
				</la:info>
				<la:errors styleClass="list-unstyled"/>
			</div>
		</div>
	</main>
	<jsp:include page="../footer.jsp" />
	<input type="hidden" id="contextPath" value="<%=request.getContextPath()%>" />
	<script type="text/javascript"

```Python hl_lines="2  14-16"
{!../../../docs_src/handling_errors/tutorial004.py!}
```

Wenn Sie nun `/items/foo` besuchen, erhalten Sie statt des Default-JSON-Errors:

```JSON
{
    "detail": [
        {
            "loc": [
                "path",
                "item_id"
            ],
            "msg": "value is not a valid integer",
            "type": "type_error.integer"
        }
    ]
}
```

The status codes in the 400 range mean that there was an error from the client.

Remember all those **"404 Not Found"** errors (and jokes)?

## Use `HTTPException`

To return HTTP responses with errors to the client you use `HTTPException`.

### Import `HTTPException`

```Python hl_lines="1"
{!../../../docs_src/handling_errors/tutorial001.py!}
```

### Raise an `HTTPException` in your code

	message    string
	statusCode int
	cause      error
}

func (err *s3Error) Cause() error {
	return err.cause
}

func (err *s3Error) ErrorCode() string {
	return err.code
}

func (err *s3Error) ErrorMessage() string {
	return err.message
}

func (err *s3Error) HTTPStatusCode() int {
	return err.statusCode
}

func (err *s3Error) Error() string {
	return err.message
}

	return &s3Error{
		code:       "InvalidQuery",
		message:    err.Error(),
		statusCode: 400,
		cause:      err,
	}
}

func errBadTableName(err error) *s3Error {
	return &s3Error{
		code:       "BadTableName",
		message:    fmt.Sprintf("The table name is not supported: %v", err),
		statusCode: 400,
		cause:      err,
	}
}

func errDataSource(err error) *s3Error {
	return &s3Error{

被替换为了以下文本格式的错误信息：

```
1 validation error
path -> item_id
  value is not a valid integer (type=type_error.integer)

```

### `RequestValidationError` vs `ValidationError`

!!! warning "警告"

    如果您觉得现在还用不到以下技术细节，可以先跳过下面的内容。


`RequestValidationError` 是 Pydantic 的 <a href="https://docs.pydantic.dev/latest/concepts/models/#error-handling" class="external-link" target="_blank">`ValidationError`</a> 的子类。

import (
	"fmt"
)

// ErrUnknownRegion - unknown region error.
type ErrUnknownRegion struct {
	Region string
}

func (err ErrUnknownRegion) Error() string {
	return fmt.Sprintf("unknown region '%v'", err.Region)
}

// ErrARNNotFound - ARN not found error.
type ErrARNNotFound struct {
	ARN ARN
}

func (err ErrARNNotFound) Error() string {
	return fmt.Sprintf("ARN '%v' not found", err.ARN)
}

	message    string
	statusCode int
	cause      error
}

func (err *s3Error) Cause() error {
	return err.cause
}

func (err *s3Error) ErrorCode() string {
	return err.code
}

func (err *s3Error) ErrorMessage() string {
	return err.message
}

func (err *s3Error) HTTPStatusCode() int {
	return err.statusCode
}

func (err *s3Error) Error() string {
	return err.message
}

```
1 validation error
path -> item_id
  value is not a valid integer (type=type_error.integer)
```

#### `RequestValidationError` 🆚 `ValidationError`

!!! warning
    👫 📡 ℹ 👈 👆 💪 🚶 🚥 ⚫️ 🚫 ⚠ 👆 🔜.

`RequestValidationError` 🎧-🎓 Pydantic <a href="https://docs.pydantic.dev/latest/concepts/models/#error-handling" class="external-link" target="_blank">`ValidationError`</a>.