Algolia Data Handling

Overview

Algolia stores your records in their cloud. You control what data goes in (via saveObjects), what comes back (via attributesToRetrieve), and what users can search (via searchableAttributes). For privacy compliance, you must filter PII before indexing and implement deletion workflows.

Data Flow: Source → Algolia → User

Source Database        Transform           Algolia Index           Search Response
┌──────────┐     ┌──────────────┐     ┌──────────────────┐     ┌──────────────┐
│ Full user │     │ Strip PII    │     │ Searchable       │     │ Retrieved    │
│ record    │ ──▶ │ Truncate     │ ──▶ │ fields only      │ ──▶ │ fields only  │
│ (all cols)│     │ Normalize    │     │ + ranking data   │     │ (UI needs)   │
└──────────┘     └──────────────┘     └──────────────────┘     └──────────────┘

Instructions

Step 1: Transform Records Before Indexing

import { algoliasearch } from 'algoliasearch';

const client = algoliasearch(process.env.ALGOLIA_APP_ID!, process.env.ALGOLIA_ADMIN_KEY!);

// Define what goes into Algolia — NOT everything from your DB
interface AlgoliaProduct {
  objectID: string;
  name: string;
  description: string;     // Truncated, plain text
  category: string;
  brand: string;
  price: number;
  in_stock: boolean;
  image_url: string;
  rating: number;
  _tags: string[];
}

function transformForAlgolia(dbRecord: any): AlgoliaProduct {
  return {
    objectID: dbRecord.id,
    name: dbRecord.name,
    description: stripHtml(dbRecord.description).substring(0, 5000),
    category: dbRecord.category?.name || 'uncategorized',
    brand: dbRecord.brand?.name || '',
    price: dbRecord.price_cents / 100,
    in_stock: dbRecord.inventory_count > 0,
    image_url: dbRecord.images?.[0]?.url || '',
    rating: dbRecord.avg_rating || 0,
    _tags: buildTags(dbRecord),
  };
}

// Strip HTML tags for clean search text
function stripHtml(html: string): string {
  return html?.replace(/<[^>]*>/g, ' ').replace(/\s+/g, ' ').trim() || '';
}

function buildTags(record: any): string[] {
  const tags: string[] = [];
  if (record.is_featured) tags.push('featured');
  if (record.is_new) tags.push('new-arrival');
  if (record.discount_percent > 0) tags.push('on-sale');
  return tags;
}

Step 2: PII Detection and Filtering

// NEVER index PII unless absolutely necessary for search
const PII_FIELDS = ['email', 'phone', 'ssn', 'address', 'credit_card', 'password', 'api_key'];

function stripPII(record: Record<string, any>): Record<string, any> {
  const clean = { ...record };
  for (const field of PII_FIELDS) {
    delete clean[field];
  }
  return clean;
}

// If you MUST index user-facing names (e.g., author names in articles)
// Use unretrievableAttributes so they're searchable but never returned
await client.setSettings({
  indexName: 'articles',
  indexSettings: {
    searchableAttributes: ['title', 'author_name', 'content'],
    unretrievableAttributes: ['author_name'],  // Searchable but never in response
    attributesToRetrieve: ['title', 'excerpt', 'url', 'published_at'],
  },
});

Step 3: Algolia-Side Data Access Control

// Use secured API keys to filter what each user can see
function generateUserKey(userId: string, tenantId: string) {
  return client.generateSecuredApiKey({
    parentApiKey: process.env.ALGOLIA_SEARCH_KEY!,
    restrictions: {
      filters: `tenant_id:${tenantId} AND (visibility:public OR created_by:${userId})`,
      validUntil: Math.floor(Date.now() / 1000) + 3600,
    },
  });
}

// User can only search records where:
// - tenant_id matches their org AND
// - visibility is public OR they created it

Step 4: GDPR Right to Deletion

// When a user requests data deletion:
async function deleteUserData(userId: string) {
  const results: Record<string, string> = {};

  // 1. Delete user's records from all indices
  for (const indexName of ['products', 'reviews', 'wishlists']) {
    try {
      await client.deleteBy({
        indexName,
        deleteByParams: { filters: `created_by:${userId}` },
      });
      results[indexName] = 'deleted';
    } catch (e) {
      results[indexName] = `failed: ${e}`;
    }
  }

  // 2. Delete Insights/Analytics data for this user
  // Algolia retains events for 90 days by default
  // Use the Insights API to request user data deletion
  await client.deleteUserToken({ userToken: userId });

  // 3. Log the deletion for compliance audit
  console.log({
    event: 'gdpr.deletion',
    userId,
    timestamp: new Date().toISOString(),
    results,
  });

  return results;
}

Step 5: Data Subject Access Request (DSAR)

// Export all data associated with a user
async function exportUserData(userId: string) {
  const exportData: Record<string, any[]> = {};

  for (const indexName of ['products', 'reviews', 'wishlists']) {
    const records: any[] = [];
    let cursor: string | undefined;

    // Browse all records matching the user
    do {
      const result = await client.browse({
        indexName,
        browseParams: {
          filters: `created_by:${userId}`,
          hitsPerPage: 1000,
          cursor,
        },
      });
      records.push(...result.hits);
      cursor = result.cursor;
    } while (cursor);

    exportData[indexName] = records;
  }

  return {
    exportedAt: new Date().toISOString(),
    userId,
    data: exportData,
  };
}

Step 6: Data Retention and Cleanup

// Scheduled job: delete old records past retention period
async function enforceRetention(indexName: string, retentionDays: number) {
  const cutoffTimestamp = Math.floor(
    (Date.now() - retentionDays * 24 * 60 * 60 * 1000) / 1000
  );

  await client.deleteBy({
    indexName,
    deleteByParams: {
      filters: `created_at_timestamp < ${cutoffTimestamp}`,
    },
  });

  console.log(`Deleted records older than ${retentionDays} days from ${indexName}`);
}

// Run daily: enforceRetention('activity_logs', 90);

Data Classification for Algolia

Category	Examples	Index It?	Retrieve It?
Public product data	Name, price, category	Yes	Yes
Searchable metadata	Tags, internal categories	Yes	No (unretrievableAttributes)
User-generated content	Reviews, comments	Yes (anonymized)	Yes
PII	Email, phone, address	NO	NO
Sensitive business data	Margins, supplier costs	NO	NO

Error Handling

Issue	Cause	Solution
PII in Algolia index	Transform didn't strip	Add PII check to indexing pipeline
deleteBy no effect	Filter doesn't match	Verify field is in attributesForFaceting
DSAR export incomplete	Paginated results	Use cursor-based browsing
Retention job deletes too much	Wrong timestamp format	Use Unix timestamp (seconds), not milliseconds

Resources

• Algolia Privacy & GDPR
• deleteBy Reference
• browse Reference
• Insights User Deletion

Next Steps

For enterprise access control, see algolia-enterprise-rbac.