Batch Operations

Batch operations allow you to work with multiple storage items at once, which is more efficient than calling individual methods in a loop.

Note

All batch methods are asynchronous and return Promises. Always use await or .then() when calling them.

batchSet()

Stores multiple items efficiently in a single operation. Each item can have its own expiration time.

Syntax

await storage.batchSet(items)

Parameters

• items (Array) — An array of objects, each with these properties:
  • key (String, required) — The key to store
  • value (Any JSON-serializable, required) — The value to store
  • expiresIn (Number, optional) — Expiration time in seconds

Returns

Promise<void>

Example

await storage.batchSet([
  { key: 'user', value: { name: 'Alice' } },
  { key: 'theme', value: 'dark' },
  { key: 'session', value: 'xyz789', expiresIn: 3600 }, // Expires in 1 hour
  { key: 'temp', value: 'test', expiresIn: 60 }         // Expires in 1 minute
]);

Use Cases

• Initializing multiple storage items when a user logs in
• Saving multiple form fields at once
• Caching multiple API responses with different expiration times
• Restoring state from a backup

Tip

batchSet() is significantly faster than calling set() multiple times in a loop, especially when compression is enabled.

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batchGet()

Retrieves multiple items in a single operation.

Syntax

await storage.batchGet(keys)

Parameters

• keys (Array of Strings) — An array of key names to retrieve

Returns

Promise<Object> — An object mapping requested keys to their values. If a key doesn’t exist or has expired, its value will be null.

Example

// Store some items
await storage.set('user', { name: 'Alice' });
await storage.set('theme', 'dark');
await storage.set('lang', 'en');

// Retrieve multiple items
const data = await storage.batchGet(['user', 'theme', 'lang', 'missing']);

console.log(data);
// Output: {
//   user: { name: 'Alice' },
//   theme: 'dark',
//   lang: 'en',
//   missing: null
// }

Use Cases

• Loading multiple settings or preferences at once
• Retrieving all data needed for a page in one operation
• Checking multiple cache entries simultaneously
• Bulk data export

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batchRemove()

Removes multiple items in a single operation.

Syntax

await storage.batchRemove(keys)

Parameters

• keys (Array of Strings) — An array of key names to remove

Returns

Promise<void>

Example

// Store some items
await storage.set('temp1', 'value1');
await storage.set('temp2', 'value2');
await storage.set('temp3', 'value3');
await storage.set('keep', 'important');

// Remove multiple items at once
await storage.batchRemove(['temp1', 'temp2', 'temp3']);

// Verify
const keys = await storage.keys();
console.log(keys); // Output: ['keep']

Use Cases

• Cleaning up temporary data
• Logging out a user (removing session, token, user data, etc.)
• Clearing cache entries
• Bulk deletion of related items

Note

batchRemove() is more efficient than calling remove() multiple times, especially for large numbers of keys.

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Complete Batch Example

Here’s a comprehensive example using all batch operations together:

// Initialize storage with multiple items
await storage.batchSet([
  { key: 'user', value: { id: 1, name: 'Alice' } },
  { key: 'session', value: 'token-xyz', expiresIn: 3600 },
  { key: 'preferences', value: { theme: 'dark', lang: 'en' } },
  { key: 'cache:posts', value: [...], expiresIn: 1800 },
  { key: 'cache:users', value: [...], expiresIn: 1800 }
]);

// Later: Load multiple items at once
const data = await storage.batchGet([
  'user',
  'session',
  'preferences',
  'cache:posts'
]);

if (data.user && data.session) {
  console.log(`Welcome back, ${data.user.name}!`);
  console.log('Theme:', data.preferences.theme);
}

// On logout: Remove all user-related data
await storage.batchRemove([
  'user',
  'session',
  'preferences',
  'cache:posts',
  'cache:users'
]);

Performance Comparison

Here’s a comparison of individual vs. batch operations:

// ❌ Inefficient: Individual operations
console.time('individual');
for (let i = 0; i < 100; i++) {
  await storage.set(`item${i}`, { value: i });
}
console.timeEnd('individual'); // ~500ms

// ✅ Efficient: Batch operation
console.time('batch');
const items = Array.from({ length: 100 }, (_, i) => ({
  key: `item${i}`,
  value: { value: i }
}));
await storage.batchSet(items);
console.timeEnd('batch'); // ~50ms

Tip

When working with multiple items, always prefer batch operations over loops. They’re faster, more efficient, and easier to read.

Next Steps

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