Conditional Requests with React InstantSearch
By default, InstantSearch sends an initial request to Algolia’s servers with an empty query. This connection helps speed up later requests.
However, sometimes you don’t want to perform more network calls than are necessary. For example, you may want to limit the number of search requests and reduce your overall Algolia usage. This guide helps you build a UI that prevents this initial request.
How a search client works
InstantSearch is the UI layer that sits on top of Algolia’s search client layer, with a state managed by the helper layer. These three layers are interchangeable so that you can leverage the InstantSearch widgets with a different search client.
The search client queries Algolia’s servers whenever the user refines the search. You can build a custom search client to add custom behavior, for example, to perform backend searches with InstantSearch.
Implementing a proxy
To prevent the initial empty query, you must wrap a custom search client around Algolia’s, and pass it to instantsearch
. The custom search client acts as a proxy for search requests:
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import { liteClient as algoliasearch } from 'algoliasearch/lite';
import { InstantSearch, SearchBox, Hits } from 'react-instantsearch';
const algoliaClient = algoliasearch(
'YourApplicationID',
'YourSearchOnlyAPIKey'
);
const searchClient = {
...algoliaClient,
search(requests) {
return algoliaClient.search(requests);
},
};
const App = () => (
<InstantSearch searchClient={searchClient} indexName="instant_search">
<SearchBox />
<Hits />
</InstantSearch>
);
This proxy lets you add some logic before calling the search
method. In this case, you only call it when performing a query.
Detecting empty search requests
If you don’t want to perform a search request when the query is empty (""
), you first need to detect it:
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const searchClient = {
...algoliaClient,
search(requests) {
if (requests.every(({ params }) => !params.query)) {
// Here we have to do something else
}
return algoliaClient.search(requests);
},
};
Sometimes, one user action results in multiple queries, for example, clicking on an refinement-list
or using multiple index-widget
widgets. Make sure that every query is empty before intercepting the function call.
When an empty search is detected, you must return a formatted response as an array of objects of the same length as the requests
array. Each object requires at least these properties: hits
, nbHits
, and processingTimeMS
.
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const searchClient = {
...algoliaClient,
search(requests) {
if (requests.every(({ params }) => !params.query)) {
return Promise.resolve({
results: requests.map(() => ({
hits: [],
nbHits: 0,
nbPages: 0,
page: 0,
processingTimeMS: 0,
hitsPerPage: 0,
exhaustiveNbHits: false,
query: '',
params: '',
})),
});
}
return algoliaClient.search(requests);
},
};
Now you can use the proxy with the instantsearch
widget, like this:
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import { liteClient as algoliasearch } from 'algoliasearch/lite';
import { InstantSearch, SearchBox, Hits } from 'react-instantsearch';
const algoliaClient = algoliasearch(
'YourApplicationID',
'YourSearchOnlyAPIKey'
);
const searchClient = {
...algoliaClient,
search(requests) {
if (requests.every(({ params }) => !params.query)) {
return Promise.resolve({
results: requests.map(() => ({
hits: [],
nbHits: 0,
nbPages: 0,
page: 0,
processingTimeMS: 0,
hitsPerPage: 0,
exhaustiveNbHits: false,
query: '',
params: '',
})),
});
}
return algoliaClient.search(requests);
},
};
const App = () => (
<InstantSearch searchClient={searchClient} indexName="instant_search">
<SearchBox />
<Hits />
</InstantSearch>
);