Faceted search

Facets are the lists of filters you see beside search results in a shop, each with a count: Audio (24), Lighting (9). ZeroIndex returns these counts in the same request as the results.

Ask for facets

Any field in filterableAttributes can be a facet. Pass the ones you want to count.

curl https://api.zeroindex.test/v1/indexes/products/search \
  -H "Authorization: Bearer $ZEROINDEX_KEY" \
  -d '{ "q": "wireless", "facets": ["category", "brand"] }'

const { hits, facetDistribution } = await client.index("products").search("wireless", {
  facets: ["category", "brand"],
});

results = client.index("products").search("wireless", {"facets": ["category", "brand"]})

The response counts how many matching documents have each value:

{
  "facetDistribution": {
    "category": { "Audio": 24, "Accessories": 11, "Lighting": 3 },
    "brand": { "Vesterlund": 17, "Casa Bruna": 12, "Tarnelli": 9 }
  }
}

Narrow down

When someone ticks a value, add it to the filter and search again. Values in the same facet are joined with OR, and different facets with AND.

const selected = { category: ["Audio"], brand: ["Vesterlund", "Tarnelli"] };

const filter = Object.entries(selected)
  .map(([field, values]) => `${field} IN [${values.map((value) => `"${value}"`).join(", ")}]`)
  .join(" AND ");

await client.index("products").search("wireless", { filter, facets: ["category", "brand"] });

Price ranges

Number fields return their lowest and highest value in facetStats. Use them to set the ends of a price slider, then filter with price 40 TO 120.

{
  "facetStats": {
    "price": { "min": 19, "max": 349 }
  }
}