/*
 * Copyright 2020 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,

/*
 * Copyright 2020 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,

/*
 * Copyright 2023 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,

        for (int i = 0; i < len; i++) {
            assertEquals(src[off + i], dst[dstIndex + i], "Byte mismatch at " + i);
        }

        // Assert: bytes before and after region remain unchanged.
        for (int i = 0; i < dstIndex; i++) {
            assertEquals((byte) 0x55, dst[i], "Unexpected change before copy region at " + i);
        }
        for (int i = dstIndex + len; i < dst.length; i++) {

 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an

// For each call, unfreezeServices must be called once.
func freezeServices() {
	// Use atomics for globalServiceFreeze, so we can read without locking.
	// We need a lock since we are need the 2 atomic values to remain in sync.
	globalServiceFreezeMu.Lock()
	// If multiple calls, first one creates channel.
	globalServiceFreezeCnt++
	if globalServiceFreezeCnt == 1 {
		globalServiceFreeze.Store(make(chan struct{}))
	}

                "HTTPValidationError": {
                    "title": "HTTPValidationError",
                    "type": "object",
                    "properties": {
                        "detail": {
                            "title": "Detail",
                            "type": "array",
                            "items": {"$ref": "#/components/schemas/ValidationError"},
                        }
                    },

            "schemas": {
                "HTTPValidationError": {
                    "properties": {
                        "detail": {
                            "items": {"$ref": "#/components/schemas/ValidationError"},
                            "type": "array",
                            "title": "Detail",
                        }
                    },
                    "type": "object",

}

```

但如果客户端请求 `http://example.com/items/bar`（`item_id` `「bar」` 不存在时），则会接收到 HTTP 状态码 - 404（「未找到」错误）及如下 JSON 响应结果：

```JSON
{
  "detail": "Item not found"
}

```

/// tip | 提示

触发 `HTTPException` 时，可以用参数 `detail` 传递任何能转换为 JSON 的值，不仅限于 `str`。

还支持传递 `dict`、`list` 等数据结构。

**FastAPI** 能自动处理这些数据，并将之转换为 JSON。

///

## 添加自定义响应头

有些场景下要为 HTTP 错误添加自定义响应头。例如，出于某些方面的安全需要。

    assert response.status_code == 401, response.text
    assert response.json() == {"detail": "Not authenticated"}


def test_incorrect_token():
    response = client.get("/items", headers={"Authorization": "Non-existent testtoken"})
    assert response.status_code == 401, response.text
    assert response.json() == {"detail": "Not authenticated"}


def test_token():