Allow individual start hook for @astrojs/node

[pReya]

Body

Summary

Not sure if this is "big enough" for its own RFC. But this is where GitHub directed me. It might just be a minor PR.

It would be very helpful, if the @astrojs/node would allow to pass a function as a start parameter, which would then be executed when the server is started.

Specifying a start hook is already a feature of the Adapter API – it would only be necessary to forward start via the Adapter configuration.

Background & Motivation

This would be useful to setup the proper server environment before the Astro application is started. E.g. setting up a cron job.

Goals

A concise, bulleted-list outlining the intended goals of this RFC.

• Allow individual user scripts to be executed when the Astro node adapter is started

Example

// https://astro.build/config
export default defineConfig({
  // Enable React to support React JSX components.
  integrations: [
    react()
  ],
  output: "server",
  adapter: node({
    mode: "standalone",
    start: () => {console.log("This will be executed before the server is started")}
  }),
});

[ematipico]

What kind of payload would you expect from this hook?

I would also argue that passing a function like this isn't a safe approach, because this is information that must be available after a build, and a function can't because it's not serialisable. Usually, we accept a path to an entry point, load it, and execute it.

[pReya]

I'd suggest it to be identical to the start function of the Adapter API.

[delucis]

Isn’t this already possible with a simple server script something like:

// ./run-server.mjs
console.log("This will be executed before the server is started");
await import("./dist/server/entry.mjs");

node ./run-server.mjs

[delucis]

I’m not a huge user of the Node adapter, so probably not best placed to say if my suggested workaround is the right one or not to document.

---

As @ematipico mentioned above, a function directly inline in the Astro config probably wouldn’t work, because the Astro config is not bundled and run in the server output. If this were ever supported, it would probably look more like an option to tell Astro to use a specific file:

node({ startEntrypoint: './start.js' })

[ematipico]

Sure, there's many workarounds to this. But they're typically easier to brake and not as comfortable as passing a function through the config file.

Would it make sense to add this solution to the docs, somewhere?

If this start method doesn't pass any information that belongs to Astro, where users can do something based on that "information," I can't see enough value in adding it, considering that you can do it yourself with a simple script.

[pReya]

Sure, there's many workarounds to this. But they're typically easier to brake and not as comfortable as passing a function through the config file.
Would it make sense to add this solution to the docs, somewhere?

If this start method doesn't pass any information that belongs to Astro, where users can do something based on that "information," I can't see enough value in adding it, considering that you can do it yourself with a simple script.

It's a common feature of many existing full-stack frameworks, to run a function once, when starting the application (e.g. Laravel, Rails, Django). I can understand your objections/the problems with the hook inside the config. But mentioning the "workaround" of writing a simple script for it could be a useful addition to the docs, don't you think?

[ematipico]

That's definitely worth adding to the docs!!

[Madd0g]

sorry, I might have missed something - did you mean that creating the wrapper file that imports entry.mjs is what's worth adding to the docs?

I'm wondering what other workarounds exist and are recommended?