kopia lustrzana https://github.com/transitive-bullshit/chatgpt-api
90 wiersze
2.3 KiB
TypeScript
90 wiersze
2.3 KiB
TypeScript
import { createParser } from 'eventsource-parser'
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import * as types from './types'
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import { fetch as globalFetch } from './fetch'
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import { streamAsyncIterable } from './stream-async-iterable'
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export async function fetchSSE(
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url: string,
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options: Parameters<typeof fetch>[1] & {
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onMessage: (data: string) => void
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onError?: (error: any) => void
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},
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fetch: types.FetchFn = globalFetch
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) {
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const { onMessage, onError, ...fetchOptions } = options
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const res = await fetch(url, fetchOptions)
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if (!res.ok) {
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let reason: string
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try {
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reason = await res.text()
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} catch (err) {
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reason = res.statusText
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}
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const msg = `ChatGPT error ${res.status}: ${reason}`
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const error = new types.ChatGPTError(msg, { cause: res })
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error.statusCode = res.status
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error.statusText = res.statusText
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throw error
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}
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const parser = createParser((event) => {
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if (event.type === 'event') {
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onMessage(event.data)
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}
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})
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// handle special response errors
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const feed = (chunk: string) => {
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let response = null
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try {
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response = JSON.parse(chunk)
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} catch {
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// ignore
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}
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if (response?.detail?.type === 'invalid_request_error') {
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const msg = `ChatGPT error ${response.detail.message}: ${response.detail.code} (${response.detail.type})`
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const error = new types.ChatGPTError(msg, { cause: response })
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error.statusCode = response.detail.code
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error.statusText = response.detail.message
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if (onError) {
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onError(error)
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} else {
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console.error(error)
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}
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// don't feed to the event parser
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return
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}
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parser.feed(chunk)
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}
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if (!res.body.getReader) {
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// Vercel polyfills `fetch` with `node-fetch`, which doesn't conform to
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// web standards, so this is a workaround...
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const body: NodeJS.ReadableStream = res.body as any
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if (!body.on || !body.read) {
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throw new types.ChatGPTError('unsupported "fetch" implementation')
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}
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body.on('readable', () => {
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let chunk: string | Buffer
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while (null !== (chunk = body.read())) {
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feed(chunk.toString())
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}
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})
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} else {
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for await (const chunk of streamAsyncIterable(res.body)) {
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const str = new TextDecoder().decode(chunk)
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feed(str)
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}
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}
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}
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