@applitools/execution-grid-tunnel/src/utils/pac-errors.js

Allows user to run tests with exection-grid and navigate to private hosts and ips

'use strict'

/**
 * Typed startup error for PAC load / compile failures.
 *
 * Shape mirrors `FrpcDownloadError` so SDK consumers can branch on the
 * same conventions (`userError === true`, custom `code`, contextual
 * fields). Runtime PAC errors per request are NOT thrown — they are
 * logged via the existing structured logger and the request falls
 * through to DIRECT (see `init-socks5-proxy-server.js`).
 *
 * Codes:
 *   - EG_TUNNEL_PAC_FILE_LOAD_FAILED  — `pacFile` path missing / unreadable
 *   - EG_TUNNEL_PAC_URL_LOAD_FAILED   — `pacUrl` fetch failed (network / 4xx / 5xx / 10s timeout)
 *   - EG_TUNNEL_PAC_COMPILE_FAILED    — PAC source is invalid JavaScript or lacks `FindProxyForURL`
 *
 * Each instance carries: `code`, `name='PacError'`, `userError=true`,
 * `sourceKind: 'file'|'script'|'url'`, `source` (path / url / '<inline>'),
 * `cause` (the underlying error).
 */
class PacError extends Error {
  constructor({code, message, sourceKind, source, cause}) {
    super(message || defaultMessage(code, sourceKind, source, cause))
    if (Error.captureStackTrace) {
      Error.captureStackTrace(this, PacError)
    }
    this.name = 'PacError'
    this.userError = true
    this.code = code
    this.sourceKind = sourceKind
    this.source = source
    this.cause = cause
  }
}

function defaultMessage(code, sourceKind, source, cause) {
  const causeMsg = cause && (cause.message || String(cause))
  switch (code) {
    case 'EG_TUNNEL_PAC_FILE_LOAD_FAILED':
      return `Failed to read PAC file at "${source}"${causeMsg ? `: ${causeMsg}` : ''}`
    case 'EG_TUNNEL_PAC_URL_LOAD_FAILED':
      return `Failed to fetch PAC URL "${source}"${causeMsg ? `: ${causeMsg}` : ''}`
    case 'EG_TUNNEL_PAC_COMPILE_FAILED':
      return `Failed to compile PAC source (${sourceKind} "${source}")${causeMsg ? `: ${causeMsg}` : ''}`
    default:
      return `PAC error (${code})${causeMsg ? `: ${causeMsg}` : ''}`
  }
}

module.exports = {PacError}