install.js should support HTTPS_PROXY environment variable

[silverwind]

The esbuild module has below rudimentary fetch implementation that does not support fetching via HTTPS proxies which means the script will run for over 4 minutes waiting for the HTTPS request to timeout in environments without direct Internet connectivity.

I'd suggest switching to make-fetch-happen for this download which is a fetch-compatible module that npm itself uses and it has full proxy support.

function fetch(url2) {
  return new Promise((resolve, reject) => {
    https.get(url2, (res) => {
      if ((res.statusCode === 301 || res.statusCode === 302) && res.headers.location)
        return fetch(res.headers.location).then(resolve, reject);
      if (res.statusCode !== 200)
        return reject(new Error(`Server responded with ${res.statusCode}`));
      let chunks = [];
      res.on("data", (chunk) => chunks.push(chunk));
      res.on("end", () => resolve(Buffer.concat(chunks)));
    }).on("error", reject);
  });
}

Related: #319

I could probably send you a pull request but I could not find the source for this script in the repo.

[evanw]

I don't want the install script to depend on additional packages. I'm going to try moving npm install before the direct download. That should handle this case while still supporting the case where npm isn't installed, since the npm command should fail instantly if it doesn't exist.

[silverwind]

What's the downside of doing npm install? Does it require golang on the system?

I guess if you don't want additional dependencies, you could replicate what these two modules are doing to support downloads via proxies:

https://github.com/Rob--W/proxy-from-env
https://github.com/gajus/global-agent

(It's a shame proxy support isn't in Node.js)

[evanw]

The downside is that npm install is slower and more complicated than just doing a HTTP request because npm itself is slow and complicated. Running npm recursively is not exactly a supported use case (e.g. it deadlocks when doing a global install without a specific workaround). People may also have overridden the npm command with something else so it's impossible to know if it'll actually do what is intended or not. That's why I'm going to keep the HTTP request fallback path. I totally agree with you about node not having proxy support :(

[silverwind]

Can confirm it's much faster now with the latest version. My CI now does only take 30s to install modules compared to 5 minutes before. Thanks.