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ocsigen / eliom

Multi-tier framework for programming web and mobile applications in OCaml.
http://eliom.org
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Be compatible with other services definitions. #420

Open dannywillems opened 7 years ago

dannywillems commented 7 years ago

Even if Eliom can define more services types than most web frameworks, it would be interesting to be compatible with other routes definitions of those other web frameworks (which are often in a text file). In this way, if someone wants to change to Eliom, it can copy the configuration file.

For example, Play (Scala & Java) uses a simple routes configuration file, see here.

vasilisp commented 7 years ago

Sounds very complicated. If we were to provide such a syntax, it would have to be very Eliom-specific to account for the Eliom typing of services and parameters. And then we have the issue of how to map this syntax to properly-typed code calling Eliom_registration.X.register (and similar functions).

dannywillems commented 7 years ago

@vasilisp What I would it's only to be able to parse configuration file like those from Play, which I don't think it's complicated. We can provide a function Eliom_services.from_file filename which returns a list of services.

agarwal commented 7 years ago

We can provide a function Eliom_services.from_file filename Eliom_services.from_file filename

What would be the type of the returned list?

dannywillems commented 7 years ago

Oh... I see what @vasilisp means.

vasilisp commented 7 years ago

For example, consider a declaration like:

GET /users/:username controllers.Users.showUser(username: String)

What would we do, or what would we put in the list? From my point of view, we would need to register a service with an appropriate suffix parameter and with Controllers.Users.show_user : string -> ... as the service handler.

The only way I can imagine implementing such a thing with OCaml/Eliom would be via a compiler "frontend" that reads this file and produces Eliom_registration.X.create calls (with appropriate paths and parameters). That could be quite an interesting project actually.

I am curious how the Java people do this. Introspection? Practically untyped handlers?

Drup commented 7 years ago

The only way I can imagine implementing such a thing with OCaml/Eliom would be via a compiler "frontend" that reads this file and produces Eliom_registration.X.create calls (with appropriate paths and parameters). That could be quite an interesting project actually.

So, a ppx ? :) That's exactly what the prototype tyxml template does.

vasilisp commented 7 years ago

I didn't call it PPX because the input is not Ocaml code with extension points, but yes, that kind of thing :).