bouchon-toolbox

A set of tools for bouchon.

## What is a selector?

A selector is a function that returns a subset of an existing collection.

They are composable and performant (by using memoization).

bouchon is providing createSelector from reselect.

filterRows

filterRows is useful to filter an array easily.

Imagine that you want to retrieve the books of an author:

import { createSelector } from 'bouchon';

const selectors = {};

selectors.all = () => state => state.books;

selectors.byId = ({author}) => state => createSelector(
  selectors.all(),
  books => books.filter(book => book.author === author)
);

It could be written easier:

import { selectors } from 'bouchon-toolbox';
const { filterRows } = selectors;

const selectors = {};

selectors.all = () => state => state.books;
selectors.byAuthor = ({author}) => filterRows(selectors.all(), 'author', author);

filterRows returns a selector that can be use inside an another selector.

For example, if you want to return the books of an author for a specific years (it can be the response of an url like /books/:author/:date), you can do like this:

import { selectors } from 'bouchon-toolbox';
const { filterRows } = selectors;

const selectors = {};

selectors.all = () => state => state.books;
selectors.byAuthor = ({author}) => filterRows(selectors.all(), 'author', author);
selectors.byDate = ({author, date}) => filterRows(selectors.byAuthor({author}), 'date', date);

extendRows

extendRows is useful to extend a collection with data of an another collection.

For example, imagine that your want the author data with your books collection:

export const selectors = {};

selectors.books = () => state => state.books;
selectors.authors = () => state => state.authors;

selectors.all = () => extendRows(
  selectors.books(),
  'author_id',
  selectors.authors(),
  'id',
  'author',
);

It will return books with their author by comparing books.author_id with authors.id (similar to a SQL join query).

Installation

npm install bouchon-toolbox