# feathers-plus/batch-loader

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> Reduce requests to backend services by batching calls and caching records.

## Installation

```
npm install @feathers-plus/batch-loader --save
```

## Documentation

Please refer to the [batch-loader documentation](https://feathers-plus.github.io/v1/batch-loader/) for more details.

## Complete Example

Here's an example of a Feathers server that uses `feathers-plus/batch-loader`. 

```js
const BatchLoader = require('@feathers-plus/batch-loader');
const { getResultsByKey, getUniqueKeys } = BatchLoader;

const usersBatchLoader = new BatchLoader(
  keys => app.service('users').find({ query: { id: { $in: getUniqueKeys(keys) } } })
    .then(result => getResultsByKey(keys, result, user => user.id, '!'))
);

app.service('comments').find()
  .then(comments => Promise.all(comments.map(comment => {
    // Attach user record
    return usersBatchLoader.load(comment.userId)
      .then(user => comment.userRecord = user);
  })))
```

## License

Copyright (c) 2017 John J. Szwaronek

Licensed under the [MIT license](LICENSE).