NOTE: This is a modified version of Jason Miller's unistore package. There have been a few improvements, but the vast majority of the code remains unchanged. Changes (listed below) are awaiting approval, and I will abandon this repo once my changes are merged upstream.
- Add TypeScript support for connecting class based components
- Add better typing for setState
- Expose ref to child components when connecting preact components. PR isn't created for this one yet because I'm not sure what the best way to handle it is. Also, it's only for preact, so probably not ready to be merged.
A tiny ~650b centralized state container with component bindings for Preact & React.
- Small footprint complements Preact nicely
- Familiar names and ideas from Redux-like libraries
- Useful data selectors to extract properties from state
- Portable actions can be moved into a common place and imported
- Functional actions are just reducers
- NEW: seamlessly run Unistore in a worker via Stockroom
This project uses node and npm. Go check them out if you don't have them locally installed.
npm install --save unistore
Then with a module bundler like webpack or rollup, use as you would anything else:
// The store:
import createStore from 'unistore'
// Preact integration
import { Provider, connect } from 'unistore/preact'
// React integration
import { Provider, connect } from 'unistore/react'
Alternatively, you can import the "full" build for each, which includes both createStore
and the integration for your library of choice:
import { createStore, Provider, connect } from 'unistore/full/preact'
The UMD build is also available on unpkg:
<!-- just unistore(): -->
<script src="https://unpkg.com/unistore/dist/unistore.umd.js"></script>
<!-- for preact -->
<script src="https://unpkg.com/unistore/full/preact.umd.js"></script>
<!-- for react -->
<script src="https://unpkg.com/unistore/full/react.umd.js"></script>
You can find the library on window.unistore
.
import createStore from 'unistore'
import { Provider, connect } from 'unistore/preact'
let store = createStore({ count: 0 })
// If actions is a function, it gets passed the store:
let actions = store => ({
// Actions can just return a state update:
increment(state) {
return { count: state.count+1 }
},
// The above example as an Arrow Function:
increment2: ({ count }) => ({ count: count+1 }),
//Actions receive current state as first parameter and any other params next
//check this function as <button onClick={incrementAndLog}>
incrementAndLog: ({ count }, event) => {
console.info(event)
return { count: count+1 }
},
// Async actions can be pure async/promise functions:
async getStuff(state) {
let res = await fetch('/foo.json')
return { stuff: await res.json() }
},
// ... or just actions that call store.setState() later:
incrementAsync(state) {
setTimeout( () => {
store.setState({ count: state.count+1 })
}, 100)
}
})
const App = connect('count', actions)(
({ count, increment }) => (
<div>
<p>Count: {count}</p>
<button onClick={increment}>Increment</button>
</div>
)
)
export default () => (
<Provider store={store}>
<App />
</Provider>
)
Make sure to have Redux devtools extension previously installed.
import createStore from 'unistore'
import devtools from 'unistore/devtools'
let initialState = { count: 0 };
let store = process.env.NODE_ENV === 'production' ? createStore(initialState) : devtools(createStore(initialState));
// ...
Creates a new store, which is a tiny evented state container.
Parameters
state
Object Optional initial state (optional, default{}
)
Examples
let store = createStore();
store.subscribe( state => console.log(state) );
store.setState({ a: 'b' }); // logs { a: 'b' }
store.setState({ c: 'd' }); // logs { a: 'b', c: 'd' }
Returns store
An observable state container, returned from createStore
Create a bound copy of the given action function.
The bound returned function invokes action() and persists the result back to the store.
If the return value of action
is a Promise, the resolved value will be used as state.
Parameters
action
Function An action of the formaction(state, ...args) -> stateUpdate
Returns Function boundAction()
Apply a partial state object to the current state, invoking registered listeners.
Parameters
update
Object An object with properties to be merged into stateoverwrite
Boolean Iftrue
, update will replace state instead of being merged into it (optional, defaultfalse
)
Register a listener function to be called whenever state is changed. Returns an unsubscribe()
function.
Parameters
listener
Function A function to call when state changes. Gets passed the new state.
Returns Function unsubscribe()
Remove a previously-registered listener function.
Parameters
listener
Function The callback previously passed tosubscribe()
that should be removed.
Retrieve the current state object.
Returns Object state
Wire a component up to the store. Passes state as props, re-renders on change.
Parameters
mapStateToProps
(Function | Array | String) A function mapping of store state to prop values, or an array/CSV of properties to map.actions
(Function | Object)? Action functions (pure state mappings), or a factory returning them. Every action function gets current state as the first parameter and any other params next
Examples
const Foo = connect('foo,bar')( ({ foo, bar }) => <div /> )
const actions = { someAction }
const Foo = connect('foo,bar', actions)( ({ foo, bar, someAction }) => <div /> )
Returns Component ConnectedComponent
Extends Component
Provider exposes a store (passed as props.store
) into context.
Generally, an entire application is wrapped in a single <Provider>
at the root.
Parameters
props
Objectprops.store
Store A {Store} instance to expose via context.
Found a problem? Want a new feature? First of all, see if your issue or idea has already been reported. If not, just open a new clear and descriptive issue.
MIT License ยฉ Luke Lindsey