),
                            sourcePsi = null,
                            token
                        )
                    },
                    sourcePsi = null,
                    token
                ),
                token
            )
        )
    }.orEmpty()

    return toKtAnnotationApplication(builder, index, arguments)
}

            token,
        )
    }
    add(FirErrors.NEW_INFERENCE_ERROR) { firDiagnostic ->
        NewInferenceErrorImpl(
            firDiagnostic.a,
            firDiagnostic as KtPsiDiagnostic,
            token,
        )
    }
    add(FirErrors.OTHER_ERROR) { firDiagnostic ->
        OtherErrorImpl(
            firDiagnostic as KtPsiDiagnostic,
            token,
        )
    }

    response = client.get("/items/", headers={"X-Token": "invalid"})
    assert response.status_code == 400, response.text
    assert response.json() == {"detail": "X-Token header invalid"}


def test_get_invalid_one_users():
    response = client.get("/users/", headers={"X-Token": "invalid"})
    assert response.status_code == 400, response.text
    assert response.json() == {"detail": "X-Token header invalid"}

		},
	},
}

func mainHandler(w http.ResponseWriter, r *http.Request) {
	token := r.FormValue("token")
	if token == "" {
		writeErrorResponse(w, errors.New("token parameter not given"))
		return
	}

	rsp, ok := tokens[token]
	if !ok {
		w.WriteHeader(http.StatusForbidden)
		return
	}

	fmt.Printf("Allowed for token: %s user: %s\n", token, rsp.User)

	w.WriteHeader(http.StatusOK)
	json.NewEncoder(w).Encode(rsp)

Se ele não ver o header de `Autorização` ou o valor não tem um token `Bearer`, vai responder com um código de erro  401 (`UNAUTHORIZED`) diretamente.

Você nem precisa verificar se o token existe para retornar um erro. Você pode ter certeza de que se a sua função for executada, ela terá um `str` nesse token.

## 返回 Token

`token` 端点的响应必须是 JSON 对象。

响应返回的内容应该包含 `token_type`。本例中用的是**Bearer**Token，因此， Token 类型应为**`bearer`**。

返回内容还应包含 `access_token` 字段，它是包含权限 Token 的字符串。

本例只是简单的演示，返回的 Token 就是 `username`，但这种方式极不安全。

!!! tip "提示"

    下一章介绍使用哈希密码和 <abbr title="JSON Web Tokens">JWT</abbr> Token 的真正安全机制。

    但现在，仅关注所需的特定细节。

```Python hl_lines="85"

def test_read_item():
    response = client.get("/items/foo", headers={"X-Token": "coneofsilence"})
    assert response.status_code == 200
    assert response.json() == {
        "id": "foo",
        "title": "Foo",
        "description": "There goes my hero",
    }


def test_read_item_bad_token():
    response = client.get("/items/foo", headers={"X-Token": "hailhydra"})
    assert response.status_code == 400

    private val builder: KtSymbolByFirBuilder,
) : KtAnnotationsList() {
    private val useSiteSession: FirSession get() = builder.rootSession
    override val token: KtLifetimeToken get() = builder.token

    override val annotations: List<KtAnnotationApplicationWithArgumentsInfo>
        get() = withValidityAssertion {
            annotations(firCallableSymbol, builder, receiverParameter)
        }

def test_items_bar_with_invalid_token(client: TestClient):
    response = client.get("/items/bar?token=jessica", headers={"X-Token": "invalid"})
    assert response.status_code == 400
    assert response.json() == {"detail": "X-Token header invalid"}


def test_items_with_missing_x_token_header(client: TestClient):
    response = client.get("/items?token=jessica")

    override val psiTypeProviderImpl = KtFirPsiTypeProvider(this, token)

    override val jvmTypeMapperImpl = KtFirJvmTypeMapper(this, token)

    override val typeProviderImpl = KtFirTypeProvider(this, token)

    override val typeInfoProviderImpl = KtFirTypeInfoProvider(this, token)

    override val subtypingComponentImpl = KtFirSubtypingComponent(this, token)