algolia-security-basics

Algolia Security Basics

Overview

Algolia's security model is built around scoped API keys. Every Algolia app has three default keys (Admin, Search-Only, Monitoring). For production, create custom keys with minimal permissions and use Secured API Keys for per-user/per-tenant restrictions.

Key Types and Where to Use Them

Key Type	ACL	Expose to Frontend?	Use Case
Admin	All operations	NEVER	Backend indexing, settings, key management
Search-Only	search only	Yes (safe)	Frontend search widgets
Monitoring	Read monitoring data	No	Health checks, dashboards
Custom	You define ACL	Depends on ACL	Scoped backend services
Secured	Derived from parent key	Yes	Per-user filtered search

Instructions

Step 1: Environment Variable Setup

# .env (NEVER commit — add to .gitignore)
ALGOLIA_APP_ID=YourApplicationID
ALGOLIA_ADMIN_KEY=admin_api_key_here        # Backend only
ALGOLIA_SEARCH_KEY=search_only_key_here     # OK for frontend

# .gitignore — MUST include:
.env
.env.local
.env.*.local

Step 2: Create Scoped API Keys

import { algoliasearch } from 'algoliasearch';

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

// Create a write-only key for a specific microservice
const { key: indexingKey } = await client.addApiKey({
  apiKey: {
    acl: ['addObject', 'deleteObject', 'editSettings'],
    description: 'Product sync service — write only',
    indexes: ['products', 'products_staging'],  // Restrict to specific indices
    maxQueriesPerIPPerHour: 5000,
    referers: [],  // Empty = no referer restriction (backend use)
  },
});

// Create a search key restricted to specific referers (frontend)
const { key: frontendKey } = await client.addApiKey({
  apiKey: {
    acl: ['search'],
    description: 'Frontend search — domain-restricted',
    indexes: ['products'],
    referers: ['https://mystore.com/*', 'https://*.mystore.com/*'],
    maxQueriesPerIPPerHour: 1000,
    maxHitsPerQuery: 50,
  },
});

Step 3: Generate Secured API Keys (Per-User Filtering)

// Secured API keys are generated on YOUR server, not via Algolia API.
// They embed restrictions that the client can't bypass.

function generateUserSearchKey(userId: string, tenantId: string): string {
  const client = algoliasearch(process.env.ALGOLIA_APP_ID!, process.env.ALGOLIA_ADMIN_KEY!);

  return client.generateSecuredApiKey({
    parentApiKey: process.env.ALGOLIA_SEARCH_KEY!,
    restrictions: {
      // User can only see their tenant's data
      filters: `tenant_id:${tenantId}`,
      // Key expires in 1 hour
      validUntil: Math.floor(Date.now() / 1000) + 3600,
      // Restrict to specific indices
      restrictIndices: ['products'],
      // Optional: restrict sources (IPs)
      restrictSources: '',
    },
  });
}

// Usage in your API endpoint:
// const userKey = generateUserSearchKey(req.user.id, req.user.tenantId);
// return { appId: process.env.ALGOLIA_APP_ID, searchKey: userKey };

Step 4: Key Rotation Procedure

async function rotateApiKey(oldKeyDescription: string) {
  const client = algoliasearch(process.env.ALGOLIA_APP_ID!, process.env.ALGOLIA_ADMIN_KEY!);

  // 1. List keys to find the old one
  const { keys } = await client.listApiKeys();
  const oldKey = keys.find(k => k.description === oldKeyDescription);
  if (!oldKey) throw new Error(`Key not found: ${oldKeyDescription}`);

  // 2. Create new key with same ACL
  const { key: newKey } = await client.addApiKey({
    apiKey: {
      acl: oldKey.acl,
      description: `${oldKeyDescription} (rotated ${new Date().toISOString().split('T')[0]})`,
      indexes: oldKey.indexes || [],
      maxQueriesPerIPPerHour: oldKey.maxQueriesPerIPPerHour || 0,
      referers: oldKey.referers || [],
    },
  });

  console.log(`New key created: ...${newKey.slice(-8)}`);
  console.log('Update your env vars, then delete the old key:');
  console.log(`  client.deleteApiKey({ key: '${oldKey.value}' })`);

  return newKey;
}

Security Checklist

• Admin key in env vars, never in frontend code or git
• .env files in .gitignore
• Frontend uses Search-Only or Secured API key
• Custom keys have minimal ACL (least privilege)
• referers set on frontend keys to prevent abuse
• maxQueriesPerIPPerHour set on all public keys
• Secured API keys have validUntil (expiration)
• Key rotation scheduled quarterly
• Git history scanned for accidentally committed keys

Error Handling

Security Issue	Detection	Mitigation
Admin key exposed in frontend	Code review, git scanning	Rotate immediately, restrict referers
Key in git history	git log -S 'ALGOLIA'	Rotate key, use git-secrets or gitleaks
Excessive ACL on key	Audit key permissions	Create scoped replacement key
Expired secured key	validUntil in the past	Generate fresh secured key

Resources

• API Keys Guide
• Secured API Keys
• API Key Restrictions

Next Steps

For production deployment, see algolia-prod-checklist.