OnDemand: async extraData

[indus]

Enter your suggestions in details:

To allow the on-demand generation of pages based on an async operation (like a fetch from an external source) the extraData function should allow Promises or async.

When I try this I get an internal server error:

site.use(onDemand({
  extraData(request: Request) {
    const searchParams = new URL(request.url).searchParams;
    const params = Object.fromEntries(searchParams.entries());

    return new Promise ((resolve, reject)=>{
      setTimeout(()=>{
        resolve({params})
      },1000)
    })
  },
}));

marking the function as async also gives an error.

I think an await in this line https://github1s.com/lumeland/lume/blob/main/middlewares/on_demand.ts#L42-L43
could do the trick to allow for async extraData functions.

[oscarotero]

That's good idea.
Do you want to work on a pull request?

[indus]

I've just opened the PR.
I haven't found any tests for the onDemand plugin I could extend...
But I've tested it with and without extraData function async and Promises. Everything looks fine.

[oscarotero]

Yep, I should add some tests to this plugin. Thank you!