React Redux Connector

Object-oriented React bindings for Redux.

Installation

npm install --save react-redux-connector

Requirements

Currently, react-redux-connector is available only as npm package. To effectively work with the library, you will also have to use transpiler like babel with es2015-classes and class-properties features enabled.

Motivation

Pretty quickly after starting using react-redux I started to feel uncomfortability of having my actions, reducer definitions and component code that actually uses former scattered among different files and places in the application. Also, I didn't like nor huge switch-case reducer functions, nor lots of same-looking small reducer functions each of which accepts repetitive (state, action) arguments pair. As a Rails developer, I felt a need of some kind of separate abstraction layer that will hoist all the redux-specific logic in a declarative and DRY way. That's how the concept of redux Connector component was born.

Documentation

react-redux-connector is inspired by Dan Abramov's awesome react-redux library. At it's lowest level it uses react-redux's subscription mechanism to redux store (this part of code was ported from react-redux), however, react-redux-connector provides completely different way of organizing react-related logic of your application and it's usage. react-redux-connector exports Connector, Connection and Reductor classes, the most important of which is, unsuprisingly, the Connector class.

Connector

Each Connector hoists all react-related logic (reducer functions, actions, dispatching, etc) and provides bindings for your React components (which are called connections).

API

Connector classes should have following properties set up:

• static $connection - the React component (view layer) that Connector provides connections for.

• static $state - the initial redux state that will be used in reducer function.

• static $namespace - the path of connector's $state in full redux's state. Should be something like 'profile.show' or 'todos.list'. It is also used for generation of action types (which will look like 'profile.show/$receive'). This property is set automatically in Connector.reduce function that generates required $reducer function (see bellow). But if connector only provides data with no action handling, appropriate $namespace should be set explicitly. Defaults to 'global'.

• static $reducer - a reducer function that should be generated with Connector.reduce function. This function should be called on behalf of your connector, i.e. static $reducer = TodosConnector.reduce(...). This function should be called like this:

static $reducer = YourConnector.reduce('your.namespace', (state) => ({
  $actionOne: (arg) => newState,
  $otherAction: (arg1, arg2) => anotherNewState
}));

By calling reduce in this way, your connector's prototype gets $$actionOne and $$otherAction methods that will dispatch corresponding action that will trigger corresponding reducer's code with arguments you've passed.

• $expose instance method that should return object that will be passed to $connection component in props. Yes, you can think of it as react-redux's mapStateToProps. This method accepts 2 arguments: $state which is current connector's state (i.e. part of the full state under connector's namespace) and state, which is full redux state. Defaults to function that simply returns $state.

$-functions

All functions in connector's prototype that start with exactly one '$' sign will be available in connector's connection component and all other nested connection components.

Example

import { Connector } from 'react-redux-connector';
import Todos from './Todos';
import { get, post, put, destroy } from 'your-requests-lib';

export default class TodosConnector extends Connector {
  static $connection = Todos;
  static $state = [];
  static $reducer = TodosConnector.reduce('todos', (state) => ({
    $receive: (items) => items,
    $addItem: (item) => [...state, item],
    $updateItem: (item) => state.map(i => i.id === item.id ? item : i),
    $removeItem: (id) => state.filter(i => i.id !== id)
  }));

  $expose($state) {
    return { items: $state };
  }

  $load() {
    return get('/todos')
      .then(response => this.$$receive(response.data));
  }

  $create(item) {
    return post('/todos', { item })
      .then(response => this.$$addItem(response.data));
  }

  $update(item) {
    return put(`/todos/${item.id}`, { item })
      .then(response => this.$$updateItem(response.data));
  }

  $destroy(id) {
    return destroy(`/todos/${id}`)
      .then(() => this.$$removeItem(id));
  }
}

External actions dispatching

If there is a need to dispatch an action of other Connector, i.e. from other namespace, that can be done using #dispatch and .action methods, like so:

// somewhere in TodosConnector.jsx

$createTodo(todo) {
  return post('/todos', { todo })
    .then(() => this.dispatch(ToolbarConnector.action('incrementTodosCount')));
}

Connection

Connection is a very simple helper object that you should inherit from instead of React.Component. Connection components can call all $-starting methods that are defined in Connector (that intended to result in dispatching an action).

Note that only explicitly connected connection (i.e. the one that is specified in connector's $connection property) gets connector's exposed state in properties. All other connections nested under that 'main' one have usual props that you've passed to them via React means, but they do have access to connector's $-functions.

Example

import { Connection } from 'react-redux-connector';

export default class Todos extends Connection {
  state = { title: '' };

  componentDidMount() {
    this.$load();
  }

  saveItem() {
    this.$create({ title: this.state.title })
      .then(() => this.setState({ title: '' }));
  }

  destroyItem(id) {
    this.$destroy(id);
  }

  render() {
    return (
      <div>
        {this.props.items.map(item =>
          <div key={item.id}>
            {item.title}
            <button onClick={() => this.destroyItem(item.id)}>Delete</button>
          </div>
        )}
        <input onChange={(e) => this.setState({ title: e.target.value })} />
        <button onClick={() => this.saveItem()}>Save</button>
      </div>
    );
  }
}

NOTE: if you don't want to inherit from Connection, you can gain access to connector's $-functions using react context:

class Todos extends Component {
  static contextTypes = {
    on: PropTypes.object
  };

  componentDidMount() {
    this.context.on.$load();
  }

  // ...
}

Actually, that's only one thing Connection does - provides a kind of syntactic sugar for calling connector's $-functions.

Reductor

Reductor is a special helper component that acts as react-redux's state provider, but it's main purpose is to generate a store reducer function for you. On initialization it will traverse all children tree looking for connectors, collect them and use to create and provide store with given createStore prop. Connectors that are not present in the children tree should be listed in connectors property. Naturally, the most obvious example is usage with react-router routes.

import { Reductor } from 'react-redux-connector';
import { createStore } from 'redux';

import Profile from 'application/ProfileConnector';
import Todos from 'application/todos/TodosCollector';
import TodoDetails from 'application/todos/TodoDetailsConnector';

export default class App extends Component {
  return (
    <Reductor createStore={createStore}>
      <Router history={history}>
        <IndexRedirect to="/profile" />
        <Route path="/profile" component={Profile} />
        <Route path="/todos" component={Todos} />
        <Route path="/todos/:id" component={TodoDetails} />
      </Router>
    </Reductor>
  );
}

Reductor Props

Prop Name	Spec	Description
createStore	required PropTypes.func	A function that takes reducer function (generated by a Reductor) as an argument and returns a redux state
connectors	optional PropTypes.arrayOf(PropTypes.func)	An array of connectors that cannot be mentioned in children tree, but whose $reducer functions should become a part of generated redux reducer function
connectorProp	optional PropTypes.string, defaults to 'component'	A prop of components in children tree that contains a Connector as a value

License

MIT