///

/// warning

你可以在一個 *路徑操作（path operation）* 中宣告多個 `Form` 參數，但不能同時再宣告期望以 JSON 接收的 `Body` 欄位，因為該請求的本文會使用 `application/x-www-form-urlencoded` 編碼，而不是 `application/json`。

這不是 **FastAPI** 的限制，而是 HTTP 協定本身的規定。

///

## 回顧 { #recap }

# Bigger Applications - Multiple Files { #bigger-applications-multiple-files }

If you are building an application or a web API, it's rarely the case that you can put everything in a single file.

**FastAPI** provides a convenience tool to structure your application while keeping all the flexibility.

/// info

If you come from Flask, this would be the equivalent of Flask's Blueprints.

///

## An example file structure { #an-example-file-structure }

                        "responses": {
                            "200": {
                                "description": "Successful Response",
                                "content": {"application/json": {"schema": {}}},
                            }
                        },
                        "security": [{"OAuth2AuthorizationCodeBearer": []}],
                    }
                },

            "content": {
                "application/json": {
                    "schema": {
                        "$ref": "#/components/schemas/Message"
                    }
                }
            }
        },
        "200": {
            "description": "Successful Response",
            "content": {
                "application/json": {
                    "schema": {

        settingTestToken();
    }

    @AfterAll
    protected static void tearDownAll() {
        deleteTestToken();
    }

    @Test
    public void testPopularWords_ok() {
        given().contentType("application/json")
                .when()
                .get("/api/v1/popular-words")
                .then()
                .statusCode(200)
                .body("record_count", greaterThanOrEqualTo(0))

                                "content": {"application/json": {"schema": {}}},
                            },
                            "422": {
                                "description": "Validation Error",
                                "content": {
                                    "application/json": {
                                        "schema": {

                                "content": {"application/json": {"schema": {}}},
                            },
                            "422": {
                                "description": "Validation Error",
                                "content": {
                                    "application/json": {
                                        "schema": {

     <span style="background-color:#007166"><font color="#D3D7CF"> INFO </font></span>  Waiting for application startup.
     <span style="background-color:#007166"><font color="#D3D7CF"> INFO </font></span>  Application startup complete.

        // Then
        assertNotNull(appKey, "Application key should not be null");
        assertEquals(16, appKey.length, "Application key should be 16 bytes");
        assertFalse(Arrays.equals(sessionKey, appKey), "Application key should be different from session key");
    }

    @Test
    @DisplayName("Should derive different application keys for different dialects")

import org.apache.maven.api.annotations.Nullable;

/**
 * Represents a hierarchical trace of nested requests within a session, enabling correlation between
 * session events and their originating operations in the application code. The trace structure
 * supports the following key features:
 *
 * <ul>
 *   <li>Maintains parent-child relationships between requests to track operation nesting</li>