{!../../docs_src/first_steps/tutorial001.py!}
```

`@app.get("/")` 告诉 **FastAPI** 在它下方的函数负责处理如下访问请求：

* 请求路径为 `/`
* 使用 <abbr title="HTTP GET 方法"><code>get</code> 操作</abbr>

/// info | "`@decorator` Info"

`@something` 语法在 Python 中被称为「装饰器」。

像一顶漂亮的装饰帽一样，将它放在一个函数的上方（我猜测这个术语的命名就是这么来的）。

装饰器接收位于其下方的函数并且用它完成一些工作。

在我们的例子中，这个装饰器告诉 **FastAPI** 位于其下方的函数对应着**路径** `/` 加上 `get` **操作**。

它是一个「**路径操作装饰器**」。

///

```Python hl_lines="6"
{!../../docs_src/first_steps/tutorial001.py!}
```

`@app.get("/")` nói **FastAPI** rằng hàm bên dưới có trách nhiệm xử lí request tới:

* đường dẫn `/`
* sử dụng một <abbr title="an HTTP GET method">toán tử<code>get</code></abbr>

/// info | Thông tin về "`@decorator`"

Cú pháp `@something` trong Python được gọi là một "decorator".

def test(path, cookies, expected_status, expected_response):
    client = TestClient(app, cookies=cookies)
    response = client.get(path)
    assert response.status_code == expected_status
    assert response.json() == expected_response


def test_openapi_schema():
    client = TestClient(app)
    response = client.get("/openapi.json")
    assert response.status_code == 200
    assert response.json() == {
        "openapi": "3.1.0",

            result.setCreatedBy(DfTypeUtil.toString(source.get("createdBy")));
            result.setCreatedTime(DfTypeUtil.toLong(source.get("createdTime")));
            result.setName(DfTypeUtil.toString(source.get("name")));
            result.setSortOrder(DfTypeUtil.toInteger(source.get("sortOrder")));
            result.setUpdatedBy(DfTypeUtil.toString(source.get("updatedBy")));

        delegate,
        acceptedViolations,
        apiSourceFolders,
        baseVersion.get(),
        mainApiChangesJsonFile.asFile,
        project.isolated.rootProject.projectDirectory,
        currentUpgradedPropertiesFile.get().asFile,
        baselineUpgradedPropertiesFile.get().asFile
    )
}
tasks.named("check").configure { dependsOn(checkBinaryCompatibility) }

   *
   * <p>If {@code !range.contains(k)}, {@link #get(Comparable) get(k)} will return the same result
   * before and after a call to {@code remove(range)}. If {@code range.contains(k)}, then after a
   * call to {@code remove(range)}, {@code get(k)} will return {@code null}.
   */
  void remove(Range<K> range);

  /**

        ComponentRequirement cr = md.getRequirements().get(0);

        assertEquals("org.codehaus.plexus.archiver.Archiver", cr.getRole());
        assertEquals("jar", cr.getRoleHint());
        assertEquals("jarArchiver", cr.getFieldName());

        ComponentDependency cd = pd.getDependencies().get(0);

        assertEquals("org.apache.maven", cd.getGroupId());

    constructorsSupplier.get().firstOrNull { c -> jvmSignature == c.signature?.toString() }?.let { predicate.match(it) } ?: false


private
fun hasFunctionAttribute(functionsSupplier: Supplier<MutableList<KmFunction>>, jvmSignature: String, predicate: AttributePredicate) =
    functionsSupplier.get().firstOrNull {
        jvmSignature == it.signature?.toString()

    client = TestClient(app, base_url="http://example.com")
    response = client.get("/")
    assert response.status_code == 200, response.text
    client = TestClient(app, base_url="http://subdomain.example.com")
    response = client.get("/")
    assert response.status_code == 200, response.text
    client = TestClient(app, base_url="http://invalidhost")
    response = client.get("/")

    assertEqualInOrder(values, multimap().get(key));

    if (!values.isEmpty()) {
      assertEqualInOrder(values, multimap().asMap().get(key));
      assertFalse(multimap().isEmpty());
    } else {
      assertNull(multimap().asMap().get(key));
    }

    assertEquals(values.size(), multimap().get(key).size());
    assertEquals(values.size() > 0, multimap().containsKey(key));