React 中来自 API 网关的 502 错误响应但适用于 postman

Question

当我通过测试位或通过 POSTMAN 向 API Gateway 上的 API 发送请求时，请求发送和接收正常，并且我可以获得预期的响应正文，但是，当我通过下面的代码发出 API 请求时，我收到 502 错误。

CORS 策略没有问题，因为我没有收到任何这些错误，这是我的请求代码和后续错误。

发布请求代码

fetch('https://4diopo9a77.execute-api.eu-west-2.amazonaws.com/DSA_API/imagedata', {
    method: 'POST',
    body :"{'A':'A'}"
}).then(function(data) {
    console.log(data)
})

控制台输出

POST `API_NAME` 502
Response {type: 'cors', url: '*API_NAME*', redirected: false, status: 502, ok: false, …}

错误 1 ​​堆栈跟踪

POSTRequest @   Home.js:15
getFileData @   Home.js:49
callCallback    @   react-dom.development.js:3945
invokeGuardedCallbackDev    @   react-dom.development.js:3994
invokeGuardedCallback   @   react-dom.development.js:4056
invokeGuardedCallbackAndCatchFirstError @   react-dom.development.js:4070
executeDispatch @   react-dom.development.js:8243
processDispatchQueueItemsInOrder    @   react-dom.development.js:8275
processDispatchQueue    @   react-dom.development.js:8288
dispatchEventsForPlugins    @   react-dom.development.js:8299
(anonymous) @   react-dom.development.js:8508
batchedEventUpdates$1   @   react-dom.development.js:22396
batchedEventUpdates @   react-dom.development.js:3745
dispatchEventForPluginEventSystem   @   react-dom.development.js:8507
attemptToDispatchEvent  @   react-dom.development.js:6005
dispatchEvent   @   react-dom.development.js:5924
unstable_runWithPriority    @   scheduler.development.js:468
runWithPriority$1   @   react-dom.development.js:11276
discreteUpdates$1   @   react-dom.development.js:22413
discreteUpdates @   react-dom.development.js:3756
dispatchDiscreteEvent   @   react-dom.development.js:5889

错误 2 详细信息

body: ReadableStream
bodyUsed: false
headers: Headers {}
ok: false
redirected: false
status: 502
statusText: ""
type: "cors"
url: "*API_NAME*"
[[Prototype]]: Response

这是 POSTMAN 请求信息的图像

Answer 1

需要将 Cors 标题添加到响应中，浏览器阻止响应，因为它没有返回标题，添加了这个并且它起作用了：

“Access-Control-Allow-Origin”：'*'

所以我在 lambda 中的返回看起来像这样：

return {
        "statusCode": 200,
        "body": json.dumps(data),
        "headers": {
            'Content-Type': 'application/JSON',
            "Access-Control-Allow-Origin": '*'
        },
    }