fingerprintjs

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import * as fs from 'fs'
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import * as readline from 'readline'
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import { spawn, SpawnOptions } from 'child_process'
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import { URL } from 'url'
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import got from 'got'
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export async function eachLineInFile(
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  filePath: string,
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  callback: (line: string) => void | Promise<void>,
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): Promise<void> {
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  const fileStream = fs.createReadStream(filePath)
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  try {
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    const reader = readline.createInterface({
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      input: fileStream,
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      crlfDelay: Infinity,
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    })
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    const iterator = reader[Symbol.asyncIterator]()
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    for (;;) {
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      const value = await iterator.next()
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      if (value.done) {
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        break
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      }
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      await callback(value.value)
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    }
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  } finally {
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    fileStream.destroy()
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  }
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}
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export async function fetchFilter(
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  url: string,
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  abort?: Promise<unknown>,
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  forceTreatAsFilter = false,
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): Promise<string[]> {
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  const request = got(url, {
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    headers: {
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      'User-Agent':
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        'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) ' +
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        'Chrome/91.0.4472.114 Safari/537.36',
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    },
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  })
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  abort?.catch(() => undefined).then(() => request.cancel())
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  const response = await request.catch((error) => {
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    if (request.isCanceled) {
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      // Never resolve the promise of the function when it's aborted
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      return new Promise<never>(() => undefined)
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    }
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    throw error
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  })
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  if (response.statusCode >= 300) {
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    throw new Error(`HTTP status ${response.statusCode} (${response.statusMessage})`)
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  }
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  if (
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    !forceTreatAsFilter &&
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    !/^( *\[Adblock Plus.*] *(\r\n|\r|\n))?( *! *[a-z].*(\r\n|\r|\n)){2}/im.test(response.body)
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  ) {
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    throw new Error("The response doesn't look like a filter")
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  }
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  const filterLines = response.body.split(/(\r\n|\r|\n)/) // AdGuard filters use \r sometimes
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  const subFilterURLs: string[] = []
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  for (const line of filterLines) {
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    const match = /^!#include +(.*?) *$/.exec(line)
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    if (match) {
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      // See https://stackoverflow.com/a/45801884/1118709
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      const subFilterURL = new URL(match[1], url).href
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      subFilterURLs.push(subFilterURL)
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    }
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  }
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  await Promise.all(
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    subFilterURLs.map(async (subFilterURL) => {
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      let subFilterLines: string[]
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      try {
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        // We expect no recursion in actual filters
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        subFilterLines = await fetchFilter(subFilterURL, abort, true)
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      } catch (error) {
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        throw new Error(`Failed to fetch a sub-filter (${subFilterURL}): ${error}`)
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      }
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      filterLines.push(...subFilterLines)
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    }),
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  )
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  return filterLines
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}
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export function runCommand(command: string, options: SpawnOptions = {}): Promise<void> {
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  return new Promise<void>((resolve, reject) => {
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    const child = spawn(command, [], { shell: true, ...options })
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    child.stdout?.pipe(process.stdout)
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    child.stderr?.pipe(process.stderr)
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    child.on('error', reject)
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    child.on('close', (code) => {
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      if (code) {
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        reject(new Error(`The ${command} command has exited with code ${code}`))
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      } else {
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        resolve()
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      }
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    })
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  })
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}
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