Files
FastGPT/src/api/fetch.ts
2023-05-03 10:27:06 +08:00

68 lines
2.0 KiB
TypeScript

import { getToken } from '../utils/user';
import { SYSTEM_PROMPT_PREFIX } from '@/constants/chat';
interface StreamFetchProps {
url: string;
data: any;
onMessage: (text: string) => void;
abortSignal: AbortController;
}
export const streamFetch = ({ url, data, onMessage, abortSignal }: StreamFetchProps) =>
new Promise<{ responseText: string; systemPrompt: string }>(async (resolve, reject) => {
try {
const res = await fetch(url, {
method: 'POST',
headers: {
'Content-Type': 'application/json',
Authorization: getToken() || ''
},
body: JSON.stringify(data),
signal: abortSignal.signal
});
const reader = res.body?.getReader();
if (!reader) return;
const decoder = new TextDecoder();
let responseText = '';
let systemPrompt = '';
const read = async () => {
try {
const { done, value } = await reader?.read();
if (done) {
if (res.status === 200) {
resolve({ responseText, systemPrompt });
} else {
const parseError = JSON.parse(responseText);
reject(parseError?.message || '请求异常');
}
return;
}
let text = decoder.decode(value).replace(/<br\/>/g, '\n');
// check system prompt
if (text.includes(SYSTEM_PROMPT_PREFIX)) {
const arr = text.split(SYSTEM_PROMPT_PREFIX);
systemPrompt = arr.pop() || '';
text = arr.join('');
}
responseText += text;
onMessage(text);
read();
} catch (err: any) {
if (err?.message === 'The user aborted a request.') {
return resolve({ responseText, systemPrompt });
}
reject(typeof err === 'string' ? err : err?.message || '请求异常');
}
};
read();
} catch (err: any) {
console.log(err, '====');
reject(typeof err === 'string' ? err : err?.message || '请求异常');
}
});