I am creating a React App that makes search request to server as the user types. I want to debounce this search request, but not sure how to implement it in my existing code:

Mobx Store:

// function which initiates a fetch request to server
@action searchPlanet = async (event) => {
            this.searchString = event.target.value;
            this.planets = await getPlanets(this.searchString);
        }

React Component calling searchPlanet:

const Search = observer(({ store }) => {
    const planetList = toJS(store.planets);
    return (
        <div>
            <div className={style.search_container}>
                <input type="text" id="search" onChange={e => store.searchPlanet(e)} value={store.searchString} placeholder="search planet" />
            </div>
        </div>
    )
})

I can't use debounce function directly on onChange because that will also delay the re-rendering of Search ponent, so the user will see the typed text after some time. But I am not able to figure out to how to implement debounce function in my store? I can do something like:

import _ from lodash

@action searchPlanet = async (event) => {
            this.searchString = event.target.value;
            this.planets = await getPlanets(this.searchString);
        }

debounceSearch = _.debounce(this.searchPlanet, 250);

The issue with this is that I can't call debounceSearch directly from Search ponent because of reason mentioned above. But I want to debounce getPlanets function, which returns a promise (I am not sure if Lodash debounce function can return the promise returned by the wrapped function)?

I am creating a React App that makes search request to server as the user types. I want to debounce this search request, but not sure how to implement it in my existing code:

Mobx Store:

// function which initiates a fetch request to server
@action searchPlanet = async (event) => {
            this.searchString = event.target.value;
            this.planets = await getPlanets(this.searchString);
        }

React Component calling searchPlanet:

const Search = observer(({ store }) => {
    const planetList = toJS(store.planets);
    return (
        <div>
            <div className={style.search_container}>
                <input type="text" id="search" onChange={e => store.searchPlanet(e)} value={store.searchString} placeholder="search planet" />
            </div>
        </div>
    )
})

I can't use debounce function directly on onChange because that will also delay the re-rendering of Search ponent, so the user will see the typed text after some time. But I am not able to figure out to how to implement debounce function in my store? I can do something like:

import _ from lodash

@action searchPlanet = async (event) => {
            this.searchString = event.target.value;
            this.planets = await getPlanets(this.searchString);
        }

debounceSearch = _.debounce(this.searchPlanet, 250);

The issue with this is that I can't call debounceSearch directly from Search ponent because of reason mentioned above. But I want to debounce getPlanets function, which returns a promise (I am not sure if Lodash debounce function can return the promise returned by the wrapped function)?

• javascript
• reactjs
• ecmascript-6
• mobx

1 Answer 1

Instead of assigning a value to planets in your searchPlanet action, you could do it in the debounced function instead.

Example

@observer
class App extends Component {
  @observable value = "";
  @observable query = "";

  onChange = action(event => {
    const { value } = event.target;
    this.value = value;
    this.search(value);
  });

  search = debounce(action(query => {
    this.query = query;
  }), 250);

  render() {
    const { value, query, onChange } = this;
    return (
      <div>
        <input value={value} onChange={onChange} />
        <div>{query}</div>
      </div>
    );
  }
}