运行示例并访问 <a href="http://127.0.0.1:8000/items/3" class="external-link" target="_blank">http://127.0.0.1:8000/items/3</a>，返回的响应如下：

```JSON
{"item_id":3}
```

/// check | 检查

注意，函数接收并返回的值是 `3`（ `int`），不是 `"3"`（`str`）。

**FastAPI** 通过类型声明自动<abbr title="将来自 HTTP 请求中的字符串转换为 Python 数据类型">**解析**请求中的数据</abbr>。

///

## 数据校验

///

## Validação de dados { #data-validation }

Mas se você for no navegador para <a href="http://127.0.0.1:8000/items/foo" class="external-link" target="_blank">http://127.0.0.1:8000/items/foo</a>, verá um bom erro HTTP:

```JSON
{
  "detail": [
    {
      "type": "int_parsing",

// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package cmd

import (
	"net/http"
	"testing"
)

func BenchmarkURLQueryForm(b *testing.B) {
	req, err := http.NewRequest(http.MethodGet, "http://localhost:9000/bucket/name?uploadId=upload&partNumber=1", http.NoBody)
	if err != nil {
		b.Fatal(err)
	}

  ~ limitations under the License.
  -->
<ruleset xmlns="http://codenarc.org/ruleset/1.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://codenarc.org/ruleset/1.0 http://codenarc.org/ruleset-schema.xsd"
         xsi:noNamespaceSchemaLocation="http://codenarc.org/ruleset-schema.xsd">
    <!--<ruleset-ref path='rulesets/basic.xml'>-->

    assertThat(cookie.matches("http://square.com".toHttpUrl())).isFalse()
  }

  @Test fun idnDomainMatches() {
    val cookie = parse("http://☃.net/".toHttpUrl(), "a=b; domain=☃.net")
    assertThat(cookie!!.matches("http://☃.net/".toHttpUrl())).isTrue()
    assertThat(cookie.matches("http://xn--n3h.net/".toHttpUrl())).isTrue()

Apache Maven
Copyright 2001-2019 The Apache Software Foundation

This product includes software developed at

var (
	// De-facto standard header keys.
	xForwardedFor    = http.CanonicalHeaderKey("X-Forwarded-For")
	xForwardedHost   = http.CanonicalHeaderKey("X-Forwarded-Host")
	xForwardedPort   = http.CanonicalHeaderKey("X-Forwarded-Port")
	xForwardedProto  = http.CanonicalHeaderKey("X-Forwarded-Proto")
	xForwardedScheme = http.CanonicalHeaderKey("X-Forwarded-Scheme")
	xRealIP          = http.CanonicalHeaderKey("X-Real-IP")
)

var (

Since HTTP requests frequently happen in parallel, connection pooling must be thread-safe.

These are the primary classes involved with establishing, sharing, and terminating connections:

// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package subnet

import (
	"net/http"
	"net/url"
	"os"
	"strings"
	"sync"

	"github.com/minio/minio/internal/config"
	"github.com/minio/pkg/v3/env"
	xnet "github.com/minio/pkg/v3/net"
)

const (
	baseURL    = "https://subnet.min.io"
	baseURLDev = "http://localhost:9000"
)

		expectErr bool
	}{
		{
			reqURL:   "http://127.0.0.1:8443/?Token=xxxxx",
			duration: time.Duration(60) * time.Minute,
		},
		{
			reqURL:    "http://127.0.0.1:8443/?DurationSeconds=9s",
			expectErr: true,
		},
		{
			reqURL:    "http://127.0.0.1:8443/?DurationSeconds=31536001",
			expectErr: true,
		},
		{
			reqURL:    "http://127.0.0.1:8443/?DurationSeconds=800",
			expectErr: true,