can electron-builder change electron download source?

[FTAndy]

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electron-packager can download electron with --mirror options, seems electron builder can not do this. Any way to download electron faster ?

[develar]

Please see https://github.com/electron-userland/electron-download

You can set the ELECTRON_MIRROR or NPM_CONFIG_ELECTRON_MIRROR environment variable to use a custom base URL for grabbing Electron zips.

[FTAndy]

@develar

function createDownloadOpts(opts: any, platform: string, arch: string, electronVersion: string) {
  const downloadOpts = Object.assign({
    cache: opts.cache,
    strictSSL: opts["strict-ssl"]
  }, opts.download)

the options doc does not declare the build.download options. i add a pr