Restore Mirage build in CI after upstream fixes

[aantron]

During #337 we discovered that many of the dependencies of dream-mirage are still being updated to mirage-crypto 1.0.0. This is fine, but it eventually prevented us from getting the Mirage build working again within a reasonable amount of time. This issue is a reminder to try it again once robur-coop/ocaml-letsencrypt#34 is released, and any other dependencies that are still waiting that we may discover subsequently.

[hannesm]

You'll need to wait for a release of the mirage tool -- with mirage/mirage#1559 being merged. I will ping you here once I think this should be a smooth sail. :)

[aantron]

Great, thank you!

[aantron]

@hannesm I see the tool has been released with that PR. Is this ready for attention again?

[hannesm]

Oh yes indeed. Sorry I forgot to notify you. With the latest mirage you should be able to get dream-mirage and its examples working :)

If you need help with that, let me know and I'll try to find some time to look into that.

[LogicalOverflow]

Is it possible that building dream-mirage currently fails? I am working on updating my dream+mirage-based web server to OCaml 5.2.1 (from 5.0.0), and updating dream to the version tagged 1.0.0-alpha8. I am using a nix-based setup and don't fully understand the interactions between opam, mirage, dune and nix so this issue might also be caused by me.

The central issue I am running into is dream-mirage.dream-paf, dream-mirage.dream-paf.alpn, dream-mirage.dream-paf, and dream-httpaf.dream-h2 required in src/mirage/dune not being found. This feels similar to #357 (comment), but I am not sure if the resolution there just stopped building dream-mirage, as (afaict) the commenter doesn't actually use mirage.

I assume this broke with a888e44, which removed all vendored dependencies and the corresponding src/vendor/dune (which contained the library stanzas for all the libraries now my build fails to locate.

I also tried migrating away from the vendored dependencies in dream-mirage (dropping https support and replacing Httpaf with Httpun for the most part), based on a888e44 changes to http, but got stuck as paf.alpn uses Httpaf instead of Httpun.