bs-dataloader

1.0.2 • Public • Published

bs-dataloader

CircleCI

This is a rewrite of dataloader js lib in reasonml for use with BuckleScript. I have a goal to make it work with native OCaml in the future but I still rely on some JavaScript structures.

Usage

module UserLoaderImpl = {
  type value = user;
  type key = userId;
 
  /* The batchLoadFun needs to wrap the returned values in Js.Result.t so that we can reject each promise instead of all */
  let batchLoadFun = userIds => batchGetUsers(userIds);
  let options: options = {batch: true, maxBatchSize: 256, cache: true};
};
 
module UserLoader = DataLoader.Make(UserLoaderImpl);
 
UserLoader.load("1")
|> Js.Promise.then_(
  user => {
    displayUser user;
    Js.Promise.resolve ();
  }
);
 
/* elsewhere in your app */
 
UserLoader.load("2")
|> Js.Promise.then_(
  user => {
    interactWithUser user;
    Js.Promsie.resolve();
  }
);

The example above will load both users at the same time with 1 request. If we later need one of the loaded users again we will get a cached version of the promise, if you need a new version from the server you can clear the key.

updateUser(~userId, ~userPatch)
|> Js.Promise.then_(_ => Js.Promise.resolve(UserLoader.clear userId))
|> Js.Promise.then_(_ => UserLoader.load("1"))
|> Js.Promise.then_(user => {
  displayUser user;
  Js.Promise.resolve ();
});

Development

Build

npm run build

Build + Watch

npm run watch

Test

npm run test

Editor

If you use vscode, Press Windows + Shift + B it will build automatically

Package Sidebar

Install

npm i bs-dataloader

Weekly Downloads

135

Version

1.0.2

License

MIT

Unpacked Size

163 kB

Total Files

12

Last publish

Collaborators

  • ulrikstrid