redux-debounced
v0.5.0
Published
Debounce middleware for Redux
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redux-debounce
Debounce middleware for Redux.
What's debounce?
Debounce allows you to discard a fast paced action from updating your state until a certain period of time passes after the last action is fired.
If you have a search that happens when someone types in a text box you can use this middleware to only fire your action after the user has stopped for a specified period of time.
$ npm install --save redux-debounced
Usage
First, add some debounce
metadata to your actions using the Flux Standard Action pattern:
const action = {
type: 'MY_ACTION',
meta: {
debounce: {
time: 300
}
}
};
To enable Redux Debounce:
import { createStore, applyMiddleware } from 'redux';
import createDebounce from 'redux-debounced';
import rootReducer from './reducers/index';
// create a store that has redux-debounced middleware enabled
const createStoreWithMiddleware = applyMiddleware(
createDebounce()
)(createStore);
const store = createStoreWithMiddleware(rootReducer);
You can also specify your own key rather than using the action type this is useful if you're already using a promise middleware.
Since promise middleware doesn't have a single type associated to it you can specify your own key for the middleware to keep track of your action being dispatched.
const action = {
types: ['MY_ACTION_REQUEST', 'MY_ACTION_SUCCESS', 'MY_ACTION_FAILURE'],
promise: () => {},
meta: {
debounce: {
time: 300,
key: 'myAction'
}
}
};
Leading or trailing debouncing
You can specify if the action should be dispatch on the leading and/or trailing edge of the debounce. This implementation is similar to the lodash _.debounce()
method. By default, leading = false
and trailing = true
. If both values are set to false
, the action will not be debounced.
const action = {
type: 'MY_ACTION',
meta: {
debounce: {
time: 300,
// The action will be dispatched at the beginning of the debounce and not at the end
leading: true,
trailing: false
}
}
};
Cancelling a Debounced Action (Advanced)
If you need to cancel a debounced action, you can set the cancel
flag to true:
const action = {
type: 'MY_ACTION',
meta: {
debounce: {
cancel: true
}
}
};
// OR
const otherAction = {
type: 'CANCEL_OTHER_ACTION',
meta: {
debounce: {
cancel: true,
key: 'MY_ACTION'
}
}
}
This works in conjunction with the custom key
metadata. This can be useful if
one action may need to cancel another debounced action (e.g., a debounced API
call that does not need to run if another action comes in).
Important - A cancel action will terminate in the middleware without propagating further. It will not show up DevTools or cause other side effects. So you cannot "piggyback" a cancel on another call at this time.
Debouncing a thunk
If you want to use redux-debounced with redux-thunk add the meta object as a property to the thunk function and the debounced middleware should be applied before the thunk middleware.
import { createStore, applyMiddleware } from 'redux';
import thunkMiddleware from 'redux-thunk';
import createDebounce from 'redux-debounced';
const store = createStore(
rootReducer,
applyMiddleware(createDebounce(), thunk)
);
export function trackCustomerSearch(key) {
const thunk = dispatch => {
console.log('Search Key ----> ', key);
};
thunk.meta = {
debounce: {
time: 2500,
key: 'TRACK_CUSTOMER_SEARCH'
}
};
return thunk;
}
Important - A key must be specified as the thunk has no type.