glennsl / bs-mongodb

Bucklescript bindings to node mongodb driver

MongoDB bindings for bucklescript

This library contains preliminary bindings to MongoDB. There is very little documentation yet, and far from all features are implemented.

This library is need-driven, I am adding bindings as I need them. If you add bindings to this, feel free to send me a pull request.

Future breaking change - be aware

When I first created the Collection.createIndex function, I needed to pass options. But it didn't occur to me then, that the options should be options. So in a future version, the options will be passed as an optional argument. Currently there is a Collection.createIndexNoOpts for a no-options call.

Handling Async code

The mongo driver is inherently async, every result is either provided to a callback, or delivered in a Promise. I personally use the callbacks with my own async handling library.

But I didn't want to push a specific async library upon any users of this library, so in order to use the library, you construct the module through a functor, that takes a CallbackHandler as argument.

This piece of code is from my project where I bind the mongo library to my async library.

include MongoDB;

module AsyncHandler : CallbackHandler with type t('a) = Async.t('a) = {
  type t('a) = Async.t('a);
  let callbackConverter = (x:callback('a)) : Async.t('a) => x |> Async.from_js;
};

include Make(AsyncHandler);

If you prefer to use a (Js.Result.t('a,MongoError.t) => unit) => unit, you can do so. I might get some examples up.

And I will try to see if I can get it to work with Promises, for those who prefer this route (the underlying node library returns a promise, if no callback is passed to the aync functions).