Get Out of a TextDecoderStream() from NodeJS

Question

当我使用res.status(400).send(err.stack);从我的express nodejs应用程序发送错误消息时，我似乎无法摆脱我在接收端设置的解码器流。

以下是我在浏览器中的代码(仅限于fetch部分):

fetch("/the/url", {
method: "POST",
body: formData,
}).then(response => {
if (response.status === 200) {
return response.blob().then((data) => {
return data;
});
} else {
return new Promise((resolve, reject) => {
let err_message = "";
let reader = response.body.pipeThrough(new TextDecoderStream()).getReader();
reader.read().then(({done, value}) => {
// When no more data needs to be consumed, close the stream
if (done) {
reject(err_message);
return;
}
// Enqueue the next data chunk into our target stream
err_message += value;
});
}).then((res) => {
return (res)
}).catch((err) => {
return (err)
});
}
}).then((res) => {
console.log(res)
}).catch((err) => {
console.log(err)
});

我在所有随后的then和catch上设置了断点，但它从未解析/拒绝。

感谢指教。

Answer 1

如果对某人有帮助，您需要对同一函数进行递归调用才能正确地爆发。根据以下内容:

fetch("/the/url", {
method: "POST",
body: formData,
}).then(response => {
if (response.status === 200) {
return response.blob().then((data) => {
return data;
});
} else {
return new Promise((resolve, reject) => {
let err_message = "";
let reader = response.body.pipeThrough(new TextDecoderStream()).getReader();
reader.read().then(function processText({done, value}) {
// When no more data needs to be consumed, close the stream
if (done) {
reject(err_message);
return;
}
// Enqueue the next data chunk into our target stream
err_message += value;
return reader.read().then(processText);
});
}).then((res) => {
return (res)
}).catch((err) => {
return (err)
});
}
}).then((res) => {
console.log(res)
}).catch((err) => {
console.log(err)
});

从https://developer.mozilla.org/en-US/docs/Web/API/ReadableStream/getReader