feat: make docusaurus serve automatically open in browser

[Zamiell]

self-explanatory

[netlify]

✅ [V2]

Built without sensitive environment variables

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[github-actions]

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[Josh-Cena]

Works very well. Thanks!

This could technically be breaking, as I'm not sure what the behavior of this would be in the CI environment. However, we do warn users to not use serve for actual deployment. I'll leave the choice to @slorber. The general direction is definitely desired: I've thought about the same.

[Zamiell]

This could technically be breaking, as I'm not sure what the behavior of this would be in the CI environment.

See: https://www.scivision.dev/ci-detect-environment-variable/

Maybe the if statement should be changed from:

if (cliOptions.open) {

to:

// This function lives in utils.ts or whatever
function inCI() {
  return process.env["CI"].toLower() === "true"; 
}

if (cliOptions.open && !inCI) {

[Josh-Cena]

We already have process.env.CI checks in deploy, and it's relatively lightweight and stable so I don't think a util function is necessary. But adding this check certainly seems desirable.

[Zamiell]

Well the check should also be added to npm start as well, right? Thus, the util function.

[Josh-Cena]

start is never meant to be run in deployment. People ought to be burnt if they do 🔥

[Zamiell]

Still, it feels less error prone to deal with both at once.
I think the actual best solution is to remove both openBrowser calls with a call to a util function called something like tryOpenBrowser with an early return for CI.
That way if a 3rd openBrowser call is ever added somewhere else, it is less likely to have this bug, since the programmer would presumably copy from the existing usages.

[Josh-Cena]

FWIW, I don't particularly like lightweight encapsulations—even less so when it's used to guard against a situation that never exists. docusaurus start starts a dev server with watch and hot reload, which doesn't make much sense in the CI/deployment environment. Had we started with the --no-open option, I won't even add the check to serve. For now, I think simply changing it to if (!process.env.CI && cliOptions.open) would suffice.

[slorber]

👍