Merge pull request #148 from transitive-bullshit/feature/browser-improvements

demos/demo.ts

+import delay from 'delay'
 import dotenv from 'dotenv-safe'
 import { oraPromise } from 'ora'
 
@@ -16,7 +17,12 @@ async function main() {
   const email = process.env.OPENAI_EMAIL
   const password = process.env.OPENAI_PASSWORD
 
-  const api = new ChatGPTAPIBrowser({ email, password, debug: true })
+  const api = new ChatGPTAPIBrowser({
+    email,
+    password,
+    debug: false,
+    minimize: true
+  })
   await api.init()
 
   const prompt =

readme.md

@@ -24,7 +24,7 @@ const response = await api.sendMessage('Hello World!')
 
 Note that this solution is not lightweight, but it does work a lot more consistently than the REST API-based versions. I'm currently using this solution to power 10 OpenAI accounts concurrently across 10 minimized Chrome windows for my [Twitter bot](https://github.com/transitive-bullshit/chatgpt-twitter-bot). 😂
 
-If you get a "ChatGPT is at capacity" error when logging in, note that this is also happening quite frequently on the official webapp. Their servers are overloaded, and we're all trying our best to offer access to this amazing technology.
+If you get a "ChatGPT is at capacity" error when logging in, note that this can also happen on the official webapp as well. Their servers get overloaded at times, and we're all trying our best to offer access to this amazing technology.
 
 To use the updated version, **make sure you're using the latest version of this package and Node.js >= 18**. Then update your code following the examples below, paying special attention to the sections on [Authentication](#authentication) and [Restrictions](#restrictions).
 
@@ -240,8 +240,6 @@ Pass `sessionToken`, `clearanceToken`, and `userAgent` to the `ChatGPTAPI` const
 
 These restrictions are for the `getOpenAIAuth` + `ChatGPTAPI` solution, which uses the unofficial API. The browser-based solution, `ChatGPTAPIBrowser`, doesn't have many of these restrictions, though you'll still have to manually bypass CAPTCHAs by hand.
 
-Note: currently `ChatGPTAPIBrowser` doesn't support continuing arbitrary conversations based on `conversationId`. You can only continue conversations in the current tab or start new conversations using the `resetThread()` function.
-
 **Please read carefully**
 
 - You must use `node >= 18` at the moment. I'm using `v19.2.0` in my testing.

src/chatgpt-api-browser.ts

 import delay from 'delay'
-import html2md from 'html-to-md'
-import pTimeout from 'p-timeout'
 import type { Browser, HTTPRequest, HTTPResponse, Page } from 'puppeteer'
+import { v4 as uuidv4 } from 'uuid'
 
+import * as types from './types'
 import { getBrowser, getOpenAIAuth } from './openai-auth'
-import { isRelevantRequest, maximizePage, minimizePage } from './utils'
+import {
+  browserPostEventStream,
+  isRelevantRequest,
+  maximizePage,
+  minimizePage
+} from './utils'
 
 export class ChatGPTAPIBrowser {
   protected _markdown: boolean
   protected _debug: boolean
+  protected _minimize: boolean
   protected _isGoogleLogin: boolean
   protected _captchaToken: string
+  protected _accessToken: string
 
   protected _email: string
   protected _password: string
@@ -31,7 +38,13 @@ export class ChatGPTAPIBrowser {
     /** @defaultValue `false` **/
     debug?: boolean
 
+    /** @defaultValue `false` **/
     isGoogleLogin?: boolean
+
+    /** @defaultValue `true` **/
+    minimize?: boolean
+
+    /** @defaultValue `undefined` **/
     captchaToken?: string
   }) {
     const {
@@ -40,6 +53,7 @@ export class ChatGPTAPIBrowser {
       markdown = true,
       debug = false,
       isGoogleLogin = false,
+      minimize = true,
       captchaToken
     } = opts
 
@@ -49,6 +63,7 @@ export class ChatGPTAPIBrowser {
     this._markdown = !!markdown
     this._debug = !!debug
     this._isGoogleLogin = !!isGoogleLogin
+    this._minimize = !!minimize
     this._captchaToken = captchaToken
   }
 
@@ -64,6 +79,9 @@ export class ChatGPTAPIBrowser {
       this._page =
         (await this._browser.pages())[0] || (await this._browser.newPage())
 
+      this._page.on('request', this._onRequest.bind(this))
+      this._page.on('response', this._onResponse.bind(this))
+
       // bypass cloudflare and login
       await getOpenAIAuth({
         email: this._email,
@@ -114,10 +132,9 @@ export class ChatGPTAPIBrowser {
       return false
     }
 
+    if (this._minimize) {
       await minimizePage(this._page)
-
-    this._page.on('request', this._onRequest.bind(this))
-    this._page.on('response', this._onResponse.bind(this))
+    }
 
     return true
   }
@@ -197,6 +214,12 @@ export class ChatGPTAPIBrowser {
     } else if (url.endsWith('api/auth/session')) {
       if (status === 403) {
         await this.handle403Error()
+      } else {
+        const session: types.SessionResult = body
+
+        if (session?.accessToken) {
+          this._accessToken = session.accessToken
+        }
       }
     }
   }
@@ -209,7 +232,9 @@ export class ChatGPTAPIBrowser {
         waitUntil: 'networkidle2',
         timeout: 2 * 60 * 1000 // 2 minutes
       })
+      if (this._minimize) {
         await minimizePage(this._page)
+      }
     } catch (err) {
       console.error(
         `ChatGPT "${this._email}" error refreshing session`,
@@ -228,121 +253,182 @@ export class ChatGPTAPIBrowser {
     }
   }
 
-  async getLastMessage(): Promise<string | null> {
-    const messages = await this.getMessages()
-
-    if (messages) {
-      return messages[messages.length - 1]
-    } else {
-      return null
-    }
-  }
-
-  async getPrompts(): Promise<string[]> {
-    // Get all prompts
-    const messages = await this._page.$$(
-      '.text-base:has(.whitespace-pre-wrap):not(:has(button:nth-child(2))) .whitespace-pre-wrap'
-    )
+  // async getLastMessage(): Promise<string | null> {
+  //   const messages = await this.getMessages()
 
-    // Prompts are always plaintext
-    return Promise.all(messages.map((a) => a.evaluate((el) => el.textContent)))
-  }
+  //   if (messages) {
+  //     return messages[messages.length - 1]
+  //   } else {
+  //     return null
+  //   }
+  // }
 
-  async getMessages(): Promise<string[]> {
-    // Get all complete messages
-    // (in-progress messages that are being streamed back don't contain action buttons)
-    const messages = await this._page.$$(
-      '.text-base:has(.whitespace-pre-wrap):has(button:nth-child(2)) .whitespace-pre-wrap'
-    )
+  // async getPrompts(): Promise<string[]> {
+  //   // Get all prompts
+  //   const messages = await this._page.$$(
+  //     '.text-base:has(.whitespace-pre-wrap):not(:has(button:nth-child(2))) .whitespace-pre-wrap'
+  //   )
 
-    if (this._markdown) {
-      const htmlMessages = await Promise.all(
-        messages.map((a) => a.evaluate((el) => el.innerHTML))
-      )
-
-      const markdownMessages = htmlMessages.map((messageHtml) => {
-        // parse markdown from message HTML
-        messageHtml = messageHtml
-          .replaceAll('Copy code</button>', '</button>')
-          .replace(/Copy code\s*<\/button>/gim, '</button>')
-
-        return html2md(messageHtml, {
-          ignoreTags: [
-            'button',
-            'svg',
-            'style',
-            'form',
-            'noscript',
-            'script',
-            'meta',
-            'head'
-          ],
-          skipTags: ['button', 'svg']
-        })
-      })
+  //   // Prompts are always plaintext
+  //   return Promise.all(messages.map((a) => a.evaluate((el) => el.textContent)))
+  // }
 
-      return markdownMessages
-    } else {
-      // plaintext
-      const plaintextMessages = await Promise.all(
-        messages.map((a) => a.evaluate((el) => el.textContent))
-      )
-      return plaintextMessages
-    }
-  }
+  // async getMessages(): Promise<string[]> {
+  //   // Get all complete messages
+  //   // (in-progress messages that are being streamed back don't contain action buttons)
+  //   const messages = await this._page.$$(
+  //     '.text-base:has(.whitespace-pre-wrap):has(button:nth-child(2)) .whitespace-pre-wrap'
+  //   )
+
+  //   if (this._markdown) {
+  //     const htmlMessages = await Promise.all(
+  //       messages.map((a) => a.evaluate((el) => el.innerHTML))
+  //     )
+
+  //     const markdownMessages = htmlMessages.map((messageHtml) => {
+  //       // parse markdown from message HTML
+  //       messageHtml = messageHtml
+  //         .replaceAll('Copy code</button>', '</button>')
+  //         .replace(/Copy code\s*<\/button>/gim, '</button>')
+
+  //       return html2md(messageHtml, {
+  //         ignoreTags: [
+  //           'button',
+  //           'svg',
+  //           'style',
+  //           'form',
+  //           'noscript',
+  //           'script',
+  //           'meta',
+  //           'head'
+  //         ],
+  //         skipTags: ['button', 'svg']
+  //       })
+  //     })
+
+  //     return markdownMessages
+  //   } else {
+  //     // plaintext
+  //     const plaintextMessages = await Promise.all(
+  //       messages.map((a) => a.evaluate((el) => el.textContent))
+  //     )
+  //     return plaintextMessages
+  //   }
+  // }
 
   async sendMessage(
     message: string,
-    opts: {
-      timeoutMs?: number
-    } = {}
+    opts: types.SendMessageOptions = {}
   ): Promise<string> {
-    const { timeoutMs } = opts
+    const {
+      conversationId,
+      parentMessageId = uuidv4(),
+      messageId = uuidv4(),
+      action = 'next',
+      // TODO
+      timeoutMs,
+      // onProgress,
+      onConversationResponse
+    } = opts
 
     const inputBox = await this._getInputBox()
-    if (!inputBox) throw new Error('not signed in')
-
-    const lastMessage = await this.getLastMessage()
-
-    await inputBox.focus()
-    const paragraphs = message.split('\n')
-    for (let i = 0; i < paragraphs.length; i++) {
-      await inputBox.type(paragraphs[i], { delay: 0 })
-      if (i < paragraphs.length - 1) {
-        await this._page.keyboard.down('Shift')
-        await inputBox.press('Enter')
-        await this._page.keyboard.up('Shift')
-      } else {
-        await inputBox.press('Enter')
+    if (!inputBox || !this._accessToken) {
+      const error = new types.ChatGPTError('Not signed in')
+      error.statusCode = 401
+      throw error
+    }
+
+    const url = `https://chat.openai.com/backend-api/conversation`
+    const body: types.ConversationJSONBody = {
+      action,
+      messages: [
+        {
+          id: messageId,
+          role: 'user',
+          content: {
+            content_type: 'text',
+            parts: [message]
           }
         }
+      ],
+      model: 'text-davinci-002-render',
+      parent_message_id: parentMessageId
+    }
 
-    const responseP = new Promise<string>(async (resolve, reject) => {
-      try {
-        do {
-          await delay(1000)
+    if (conversationId) {
+      body.conversation_id = conversationId
+    }
+
+    // console.log('>>> EVALUATE', url, this._accessToken, body)
+    const result = await this._page.evaluate(
+      browserPostEventStream,
+      url,
+      this._accessToken,
+      body,
+      timeoutMs
+    )
+    // console.log('<<< EVALUATE', result)
 
-          // TODO: this logic needs some work because we can have repeat messages...
-          const newLastMessage = await this.getLastMessage()
-          if (
-            newLastMessage &&
-            lastMessage?.toLowerCase() !== newLastMessage?.toLowerCase()
-          ) {
-            return resolve(newLastMessage)
+    if (result.error) {
+      const error = new types.ChatGPTError(result.error.message)
+      error.statusCode = result.error.statusCode
+      error.statusText = result.error.statusText
+
+      if (error.statusCode === 403) {
+        await this.handle403Error()
       }
-        } while (true)
-      } catch (err) {
-        return reject(err)
+
+      throw error
     }
-    })
 
-    if (timeoutMs) {
-      return pTimeout(responseP, {
-        milliseconds: timeoutMs
-      })
-    } else {
-      return responseP
+    // TODO: support sending partial response events
+    if (onConversationResponse) {
+      onConversationResponse(result.conversationResponse)
     }
+
+    return result.response
+
+    // const lastMessage = await this.getLastMessage()
+
+    // await inputBox.focus()
+    // const paragraphs = message.split('\n')
+    // for (let i = 0; i < paragraphs.length; i++) {
+    //   await inputBox.type(paragraphs[i], { delay: 0 })
+    //   if (i < paragraphs.length - 1) {
+    //     await this._page.keyboard.down('Shift')
+    //     await inputBox.press('Enter')
+    //     await this._page.keyboard.up('Shift')
+    //   } else {
+    //     await inputBox.press('Enter')
+    //   }
+    // }
+
+    // const responseP = new Promise<string>(async (resolve, reject) => {
+    //   try {
+    //     do {
+    //       await delay(1000)
+
+    //       // TODO: this logic needs some work because we can have repeat messages...
+    //       const newLastMessage = await this.getLastMessage()
+    //       if (
+    //         newLastMessage &&
+    //         lastMessage?.toLowerCase() !== newLastMessage?.toLowerCase()
+    //       ) {
+    //         return resolve(newLastMessage)
+    //       }
+    //     } while (true)
+    //   } catch (err) {
+    //     return reject(err)
+    //   }
+    // })
+
+    // if (timeoutMs) {
+    //   return pTimeout(responseP, {
+    //     milliseconds: timeoutMs
+    //   })
+    // } else {
+    //   return responseP
+    // }
   }
 
   async resetThread() {

src/openai-auth.ts

@@ -127,7 +127,7 @@ export async function getOpenAIAuth({
         }
 
         await page.click('button[type="submit"]')
-        await page.waitForSelector('#password')
+        await page.waitForSelector('#password', { timeout: timeoutMs })
         await page.type('#password', password, { delay: 10 })
         submitP = () => page.click('button[type="submit"]')
       }

src/types.ts

@@ -297,3 +297,19 @@ export class ChatGPTError extends Error {
   response?: Response
   originalError?: Error
 }
+
+export type ChatError = {
+  error: { message: string; statusCode?: number; statusText?: string }
+  response: null
+  conversationId?: string
+  messageId?: string
+  conversationResponse?: ConversationResponseEvent
+}
+
+export type ChatResponse = {
+  error: null
+  response: string
+  conversationId: string
+  messageId: string
+  conversationResponse?: ConversationResponseEvent
+}

src/utils.ts

+import type * as PTimeoutTypes from 'p-timeout'
+import type {
+  EventSourceParseCallback,
+  EventSourceParser
+} from 'eventsource-parser'
 import type { Page } from 'puppeteer'
 import { remark } from 'remark'
 import stripMarkdown from 'strip-markdown'
 
+import * as types from './types'
+
 export function markdownToText(markdown?: string): string {
   return remark()
     .use(stripMarkdown)
@@ -44,7 +51,10 @@ export function isRelevantRequest(url: string): boolean {
     return false
   }
 
-  if (pathname.startsWith('/_next')) {
+  if (
+    !pathname.startsWith('/backend-api/') &&
+    !pathname.startsWith('/api/auth/session')
+  ) {
     return false
   }
 
@@ -54,3 +64,467 @@ export function isRelevantRequest(url: string): boolean {
 
   return true
 }
+
+/**
+ * This function is injected into the ChatGPT webapp page using puppeteer. It
+ * has to be fully self-contained, so we copied a few third-party sources and
+ * included them in here.
+ */
+export async function browserPostEventStream(
+  url: string,
+  accessToken: string,
+  body: types.ConversationJSONBody,
+  timeoutMs?: number
+): Promise<types.ChatError | types.ChatResponse> {
+  // Workaround for https://github.com/esbuild-kit/tsx/issues/113
+  globalThis.__name = () => undefined
+
+  class TimeoutError extends Error {
+    readonly name: 'TimeoutError'
+
+    constructor(message) {
+      super(message)
+      this.name = 'TimeoutError'
+    }
+  }
+
+  /**
+    An error to be thrown when the request is aborted by AbortController.
+    DOMException is thrown instead of this Error when DOMException is available.
+  */
+  class AbortError extends Error {
+    constructor(message) {
+      super()
+      this.name = 'AbortError'
+      this.message = message
+    }
+  }
+
+  const BOM = [239, 187, 191]
+
+  let conversationResponse: types.ConversationResponseEvent
+  let conversationId: string = body?.conversation_id
+  let messageId: string = body?.messages?.[0]?.id
+  let response = ''
+
+  try {
+    console.log('browserPostEventStream', url, accessToken, body)
+
+    let abortController: AbortController = null
+    if (timeoutMs) {
+      abortController = new AbortController()
+    }
+
+    const res = await fetch(url, {
+      method: 'POST',
+      body: JSON.stringify(body),
+      signal: abortController?.signal,
+      headers: {
+        accept: 'text/event-stream',
+        'x-openai-assistant-app-id': '',
+        authorization: `Bearer ${accessToken}`,
+        'content-type': 'application/json'
+      }
+    })
+
+    console.log('browserPostEventStream response', res)
+
+    if (!res.ok) {
+      return {
+        error: {
+          message: `ChatGPTAPI error ${res.status || res.statusText}`,
+          statusCode: res.status,
+          statusText: res.statusText
+        },
+        response: null,
+        conversationId,
+        messageId
+      }
+    }
+
+    const responseP = new Promise<types.ChatResponse>(
+      async (resolve, reject) => {
+        function onMessage(data: string) {
+          if (data === '[DONE]') {
+            return resolve({
+              error: null,
+              response,
+              conversationId,
+              messageId,
+              conversationResponse
+            })
+          }
+
+          try {
+            const convoResponseEvent: types.ConversationResponseEvent =
+              JSON.parse(data)
+            conversationResponse = convoResponseEvent
+            if (convoResponseEvent.conversation_id) {
+              conversationId = convoResponseEvent.conversation_id
+            }
+
+            if (convoResponseEvent.message?.id) {
+              messageId = convoResponseEvent.message.id
+            }
+
+            const partialResponse =
+              convoResponseEvent.message?.content?.parts?.[0]
+            if (partialResponse) {
+              response = partialResponse
+            }
+          } catch (err) {
+            console.warn('fetchSSE onMessage unexpected error', err)
+            reject(err)
+          }
+        }
+
+        const parser = createParser((event) => {
+          if (event.type === 'event') {
+            onMessage(event.data)
+          }
+        })
+
+        for await (const chunk of streamAsyncIterable(res.body)) {
+          const str = new TextDecoder().decode(chunk)
+          parser.feed(str)
+        }
+      }
+    )
+
+    if (timeoutMs) {
+      if (abortController) {
+        // This will be called when a timeout occurs in order for us to forcibly
+        // ensure that the underlying HTTP request is aborted.
+        ;(responseP as any).cancel = () => {
+          abortController.abort()
+        }
+      }
+
+      return await pTimeout(responseP, {
+        milliseconds: timeoutMs,
+        message: 'ChatGPT timed out waiting for response'
+      })
+    } else {
+      return await responseP
+    }
+  } catch (err) {
+    const errMessageL = err.toString().toLowerCase()
+
+    if (
+      response &&
+      (errMessageL === 'error: typeerror: terminated' ||
+        errMessageL === 'typeerror: terminated')
+    ) {
+      // OpenAI sometimes forcefully terminates the socket from their end before
+      // the HTTP request has resolved cleanly. In my testing, these cases tend to
+      // happen when OpenAI has already send the last `response`, so we can ignore
+      // the `fetch` error in this case.
+      return {
+        error: null,
+        response,
+        conversationId,
+        messageId,
+        conversationResponse
+      }
+    }
+
+    return {
+      error: {
+        message: err.toString(),
+        statusCode: err.statusCode || err.status || err.response?.statusCode,
+        statusText: err.statusText || err.response?.statusText
+      },
+      response: null,
+      conversationId,
+      messageId,
+      conversationResponse
+    }
+  }
+
+  async function* streamAsyncIterable<T>(stream: ReadableStream<T>) {
+    const reader = stream.getReader()
+    try {
+      while (true) {
+        const { done, value } = await reader.read()
+        if (done) {
+          return
+        }
+        yield value
+      }
+    } finally {
+      reader.releaseLock()
+    }
+  }
+
+  // @see https://github.com/rexxars/eventsource-parser
+  function createParser(onParse: EventSourceParseCallback): EventSourceParser {
+    // Processing state
+    let isFirstChunk: boolean
+    let buffer: string
+    let startingPosition: number
+    let startingFieldLength: number
+
+    // Event state
+    let eventId: string | undefined
+    let eventName: string | undefined
+    let data: string
+
+    reset()
+    return { feed, reset }
+
+    function reset(): void {
+      isFirstChunk = true
+      buffer = ''
+      startingPosition = 0
+      startingFieldLength = -1
+
+      eventId = undefined
+      eventName = undefined
+      data = ''
+    }
+
+    function feed(chunk: string): void {
+      buffer = buffer ? buffer + chunk : chunk
+
+      // Strip any UTF8 byte order mark (BOM) at the start of the stream.
+      // Note that we do not strip any non - UTF8 BOM, as eventsource streams are
+      // always decoded as UTF8 as per the specification.
+      if (isFirstChunk && hasBom(buffer)) {
+        buffer = buffer.slice(BOM.length)
+      }
+
+      isFirstChunk = false
+
+      // Set up chunk-specific processing state
+      const length = buffer.length
+      let position = 0
+      let discardTrailingNewline = false
+
+      // Read the current buffer byte by byte
+      while (position < length) {
+        // EventSource allows for carriage return + line feed, which means we
+        // need to ignore a linefeed character if the previous character was a
+        // carriage return
+        // @todo refactor to reduce nesting, consider checking previous byte?
+        // @todo but consider multiple chunks etc
+        if (discardTrailingNewline) {
+          if (buffer[position] === '\n') {
+            ++position
+          }
+          discardTrailingNewline = false
+        }
+
+        let lineLength = -1
+        let fieldLength = startingFieldLength
+        let character: string
+
+        for (
+          let index = startingPosition;
+          lineLength < 0 && index < length;
+          ++index
+        ) {
+          character = buffer[index]
+          if (character === ':' && fieldLength < 0) {
+            fieldLength = index - position
+          } else if (character === '\r') {
+            discardTrailingNewline = true
+            lineLength = index - position
+          } else if (character === '\n') {
+            lineLength = index - position
+          }
+        }
+
+        if (lineLength < 0) {
+          startingPosition = length - position
+          startingFieldLength = fieldLength
+          break
+        } else {
+          startingPosition = 0
+          startingFieldLength = -1
+        }
+
+        parseEventStreamLine(buffer, position, fieldLength, lineLength)
+
+        position += lineLength + 1
+      }
+
+      if (position === length) {
+        // If we consumed the entire buffer to read the event, reset the buffer
+        buffer = ''
+      } else if (position > 0) {
+        // If there are bytes left to process, set the buffer to the unprocessed
+        // portion of the buffer only
+        buffer = buffer.slice(position)
+      }
+    }
+
+    function parseEventStreamLine(
+      lineBuffer: string,
+      index: number,
+      fieldLength: number,
+      lineLength: number
+    ) {
+      if (lineLength === 0) {
+        // We reached the last line of this event
+        if (data.length > 0) {
+          onParse({
+            type: 'event',
+            id: eventId,
+            event: eventName || undefined,
+            data: data.slice(0, -1) // remove trailing newline
+          })
+
+          data = ''
+          eventId = undefined
+        }
+        eventName = undefined
+        return
+      }
+
+      const noValue = fieldLength < 0
+      const field = lineBuffer.slice(
+        index,
+        index + (noValue ? lineLength : fieldLength)
+      )
+      let step = 0
+
+      if (noValue) {
+        step = lineLength
+      } else if (lineBuffer[index + fieldLength + 1] === ' ') {
+        step = fieldLength + 2
+      } else {
+        step = fieldLength + 1
+      }
+
+      const position = index + step
+      const valueLength = lineLength - step
+      const value = lineBuffer
+        .slice(position, position + valueLength)
+        .toString()
+
+      if (field === 'data') {
+        data += value ? `${value}\n` : '\n'
+      } else if (field === 'event') {
+        eventName = value
+      } else if (field === 'id' && !value.includes('\u0000')) {
+        eventId = value
+      } else if (field === 'retry') {
+        const retry = parseInt(value, 10)
+        if (!Number.isNaN(retry)) {
+          onParse({ type: 'reconnect-interval', value: retry })
+        }
+      }
+    }
+  }
+
+  function hasBom(buffer: string) {
+    return BOM.every(
+      (charCode: number, index: number) => buffer.charCodeAt(index) === charCode
+    )
+  }
+
+  /**
+    TODO: Remove AbortError and just throw DOMException when targeting Node 18.
+   */
+  function getDOMException(errorMessage) {
+    return globalThis.DOMException === undefined
+      ? new AbortError(errorMessage)
+      : new DOMException(errorMessage)
+  }
+
+  /**
+    TODO: Remove below function and just 'reject(signal.reason)' when targeting Node 18.
+   */
+  function getAbortedReason(signal) {
+    const reason =
+      signal.reason === undefined
+        ? getDOMException('This operation was aborted.')
+        : signal.reason
+
+    return reason instanceof Error ? reason : getDOMException(reason)
+  }
+
+  // @see https://github.com/sindresorhus/p-timeout
+  function pTimeout<ValueType, ReturnType = ValueType>(
+    promise: PromiseLike<ValueType>,
+    options: PTimeoutTypes.Options<ReturnType>
+  ): PTimeoutTypes.ClearablePromise<ValueType | ReturnType> {
+    const {
+      milliseconds,
+      fallback,
+      message,
+      customTimers = { setTimeout, clearTimeout }
+    } = options
+
+    let timer
+
+    const cancelablePromise = new Promise((resolve, reject) => {
+      if (typeof milliseconds !== 'number' || Math.sign(milliseconds) !== 1) {
+        throw new TypeError(
+          `Expected \`milliseconds\` to be a positive number, got \`${milliseconds}\``
+        )
+      }
+
+      if (milliseconds === Number.POSITIVE_INFINITY) {
+        resolve(promise)
+        return
+      }
+
+      if (options.signal) {
+        const { signal } = options
+        if (signal.aborted) {
+          reject(getAbortedReason(signal))
+        }
+
+        signal.addEventListener('abort', () => {
+          reject(getAbortedReason(signal))
+        })
+      }
+
+      timer = customTimers.setTimeout.call(
+        undefined,
+        () => {
+          if (fallback) {
+            try {
+              resolve(fallback())
+            } catch (error) {
+              reject(error)
+            }
+
+            return
+          }
+
+          const errorMessage =
+            typeof message === 'string'
+              ? message
+              : `Promise timed out after ${milliseconds} milliseconds`
+          const timeoutError =
+            message instanceof Error ? message : new TimeoutError(errorMessage)
+
+          if (typeof (promise as any).cancel === 'function') {
+            ;(promise as any).cancel()
+          }
+
+          reject(timeoutError)
+        },
+        milliseconds
+      )
+      ;(async () => {
+        try {
+          resolve(await promise)
+        } catch (error) {
+          reject(error)
+        } finally {
+          customTimers.clearTimeout.call(undefined, timer)
+        }
+      })()
+    })
+
+    ;(cancelablePromise as any).clear = () => {
+      customTimers.clearTimeout.call(undefined, timer)
+      timer = undefined
+    }
+
+    return cancelablePromise as any
+  }
+}