Search and autocomplete

{
  "object": "list",
  "url": "/v1/search/suggest",
  "data": [
    {
      "id": "addr-100023336956",
      "title": "10 Downing Street, London, SW1A 2AA",
      "main_text": "10 Downing Street, London, SW1A 2AA",
      "type": "address",
      "source": "address",
      "score": 18.4,
      "relevanceScore": 1,
      "uprn": "100023336956",
      "matched_substrings": [
        { "offset": 0, "length": 2 },
        { "offset": 3, "length": 7 },
        { "offset": 11, "length": 6 }
      ],
      "main_text_matched_substrings": [
        { "offset": 0, "length": 2 },
        { "offset": 3, "length": 7 },
        { "offset": 11, "length": 6 }
      ]
    }
  ],
  "has_more": false,
  "total_count": 1,
  "search_id": "3f8a2c1e-9b7d-4e6f-8a2c-1e9b7d4e6f8a",
  "set_complete": true,
  "metadata": { "processingTime": "38ms" }
}

// Browser code. /api/suggest is your backend route: it calls
// vepler.search.searchSuggest({ q, limit: '100' }) and returns the result as JSON.
interface Row { title: string; uprn?: string }
interface Suggestions { data: Row[]; searchId?: string | null; setComplete?: boolean }

let held: { query: string; rows: Row[] } | null = null;
let inFlight: AbortController | null = null;

const words = (text: string): string[] => text.toLowerCase().split(/[^a-z0-9]+/).filter(Boolean);

function narrow(rows: Row[], query: string): Row[] {
  const queryWords = words(query);
  return rows.filter((row) => {
    const titleWords = words(row.title);
    return queryWords.every((word) => titleWords.some((titleWord) => titleWord.startsWith(word)));
  });
}

// Call after a pause in typing. Resolves to null when a newer call replaced this one.
export async function suggest(input: string): Promise<Row[] | null> {
  inFlight?.abort();
  const query = input.trim();
  if (query.length < 3) return [];

  if (held && query.toLowerCase().startsWith(held.query.toLowerCase())) {
    const rows = narrow(held.rows, query);
    if (rows.length > 0) return rows; // answered from the set, no request
  }

  const controller = new AbortController();
  inFlight = controller;
  try {
    const res = await fetch(`/api/suggest?q=${encodeURIComponent(query)}`, { signal: controller.signal });
    if (!res.ok) throw new Error(`Suggest failed with status ${res.status}`);
    const body: Suggestions = await res.json();
    held = body.searchId && body.setComplete ? { query, rows: body.data } : null;
    return body.data;
  } catch (error) {
    if (controller.signal.aborted) return null;
    throw error;
  }
}

import { SDK } from '@vepler/sdk';
import { HTTPClient } from '@vepler/sdk/lib/http';

const httpClient = new HTTPClient();
httpClient.addHook('response', (res) => {
  console.log(res.url, res.headers.get('X-Credits-Charged'), res.headers.get('X-Already-Charged'));
});

const vepler = new SDK({ apiKeyAuth: process.env.VEPLER_API_KEY, httpClient });