document server initialization step

[andykais]

It turns out something that is fairly difficult to set up in sveltekit its pretty easy to add in fresh. I am referring to having an explicit server initialization step (e.g. connect to databases, pull down assets, etc). It looks like this:

main.ts:

/// <reference no-default-lib="true" />
/// <reference lib="dom" />
/// <reference lib="dom.asynciterable" />
/// <reference lib="deno.ns" />
/// <reference lib="deno.unstable" />

import { start } from "$fresh/server.ts";
import manifest from "./fresh.gen.ts";
import { Context } from './routes/_middleware.ts'

await Context.init()
await start(manifest);

routes/_middleware.ts:

import { MiddlewareHandlerContext } from "$fresh/server.ts";
import { Database } from '../database.ts'

export interface State {
  context: Context
}

export class Context {
  private static context: Context

  public constructor() {
    this.database = new Database('sqlite.db')
  }

  public static async init() {
    Context.context = new Context()
  }

  public static instance() {
    if (this.context) return this.context
    else throw new Error('Context is not initialized!')
  }
}

export async function handler(
  req: Request,
  ctx: MiddlewareHandlerContext<State>,
) {
  ctx.state.context = Context.instance()
  const resp = await ctx.next();
  return resp;
}

I can see this being useful for a lot of devs, since setup steps are pretty universal to fullstack apps. Imo its probably worth documenting.

[lucacasonato]

That makes sense. @dsherret, I think you were looking for some documentation on this too, right?

I'd be happy to merge a PR that adds a doc page for this pattern.