Cache

The cache manager provides simple key-value storage at a high-speed data storage layer (Redis) speeding up data set and get operations.

The values stored can be a single JSON object, an array of objects or primitive values (e.g., numbes, text, boolean). Values can be stored with an optional time-to-live (TTL) to automatically expire entries.

info

You can directly store primitive values such as integers, strings, etc.,

• However, when you try to get them Altogic returns them wrapped in a simple object with a key named value.

• As an example, if you store a text field "Hello world!" at a key named "welcome" when you try to get the value of this key using the get method, you will receive the following response:

  { "value": "Hello world!" }

Set items in cache

You can set items in the cache using the set method and overwrite any existing value already set. If TTL (time to live) is specified, it automatically sets the stored entry to expire in specified seconds. Any previous TTL associated with the key is discarded on a successful set operation.

Javascript

let key = "lastUserOrder";

// Store items in cache
const { errors } = await altogic.cache.set(key, {
  productId: "prd000234",
  quantity: 12,
  customerId: "61fbf6ceeeed063ab062ac05",
  createdAt: "2022-02-09T10:55:34.562+00:00",
});

Dart

final key = "lastUserOrder";

// Store items in cache
final errors  = await altogic.cache.set(key, {
  "productId": "prd000234",
  "quantity": 12,
  "customerId": "61fbf6ceeeed063ab062ac05",
  "createdAt": "2022-02-09T10:55:34.562+00:00",
});

Parameters

Here you can find parameters for the set method.

#	Name	Data type	Required	Description
1	key	string	Yes	The key you want to set, must be a string.
2	value	any	Yes	The value you want to set in redis key-value pair.
3	ttl	number	No	The number of time to live in seconds.

caution

There is a limit on the size of the objects that you can cache. For free environments each cache key can hold max 5kB of data. If you try to cache an object which is more than this limit then you will receive an cache_key_size_exceeded error.

note

If the client library key is set to enforce session, an active user session is required (e.g., user needs to be logged in) to call this method.

Get item from cache

You can retrieve items from cache by using the get method.

Javascript

let key = "lastUserOrder";

// Query items from cache with using the `key`
const result = await altogic.cache.get(key);

Dart

final key = "lastUserOrder";

// Query items from cache with using the `key`
final result = await altogic.cache.get(key).asMap();

Example response

{
  "data": {
    "productId": "prd000234",
    "quantity": 12,
    "customerId": "61fbf6ceeeed063ab062ac05",
    "createdAt": "2022-02-09T10:55:34.562+00:00"
  },
  "errors": null
}

Parameters

Here you can find parameters for the get method.

#	Name	Data type	Required	Description
1	key	string	Yes	The key you want to get, must be a string.

note

If the client library key is set to enforce session, an active user session is required (e.g., user needs to be logged in) to call this method.

Delete items from cache

You can delete items from cache using the delete method. It removes the specified key from the cache.

Javascript

let key = "lastUserOrder";

// Delete items from cache by key
const { errors } = await altogic.cache.delete(key);

Dart

final key = "lastUserOrder";

// Delete items from cache by key 
final errors = await altogic.cache.delete(key);

Parameters

Here you can find parameters for the delete method.

#	Name	Data type	Required	Description
1	key	string	Yes	The key you want to delete, must be a string.

note

If the client library key is set to enforce session, an active user session is required (e.g., user needs to be logged in) to call this method.

Set cache expiry time

You can set cache expiry time using the expire method. It sets a timeout on key. After the timeout has expired, the key will automatically be deleted.

Javascript

let key = "lastUserOrder";

// Set cache expiry time 60 seconds
const { errors } = await altogic.cache.expire(key, 60);

Dart

final key = "lastUserOrder";

// Set cache expiry time 60 seconds
final errors = await altogic.cache.expire(key, 60);

Parameters

Here you can find parameters for the expire method.

#	Name	Data type	Required	Description
1	key	string	Yes	The key you want to expire must be a string.
2	ttl	number	No	The number of time to live in seconds.

note

If the client library key is set to enforce session, an active user session is required (e.g., user needs to be logged in) to call this method.

Increment value

You can increment value using the increment method. It increments the value of the number stored at the key by the increment amount.

Javascript

let key = "counter";

// Increment 'lastUserOrder' value by 1
const result = await altogic.cache.increment(key, 1);

Dart

final key = "counter";

// Increment 'lastUserOrder' value by 1
final result = await altogic.cache.increment(key, increment: 1);

Example response

{ "data": { "value": 2 }, "errors": null }

info

If increment amount is not specified, increments the number stored at key by one.

• If the key does not exist, it is set to 0 before performing the operation.
• If ttl specified, sets the stored entry to automatically expire in specified seconds.
• Any previous time to live associated with the key is discarded on successful increment operation.

Parameters

Here you can find parameters for the increment method.

#	Name	Data type	Required	Description
1	key	string	Yes	The key you want to increment must be a string.
2	increment	number	Yes	The increment number of the cache value.
3	ttl	number	No	The number of time to live in seconds.

note

If the client library key is set to enforce session, an active user session is required (e.g., user needs to be logged in) to call this method.

Decrement value

You can decrement value using the decrement method. It decrements the value of the number stored at the key by the decrement amount.

Javascript

let key = "lastUserOrder";

// Decrement lastUserOrder's value by 1
const result = await altogic.cache.increment(key, 1);

Dart

let key = "lastUserOrder";

// Decrement lastUserOrder's value by 1
const result = await altogic.cache.decrement(key, decrement: 1);

Example response

{ "data": { "value": 1 }, "errors": null }

info

If decrement amount is not specified, decrements the number stored at key by one.

• If the key does not exist, it is set to 0 before performing the operation.
• If ttl specified, sets the stored entry to automatically expire in specified seconds.
• Any previous time to live associated with the key is discarded on successful decrement operation.

Parameters

Here you can find parameters for the decrement method.

#	Name	Data type	Required	Description
1	key	string	Yes	The key you want to decrement must be a string.
2	decrement	number	Yes	The decrement number of the cache value.
3	ttl	number	No	The number of time to live in seconds.

note

If the client library key is set to enforce session, an active user session is required (e.g., user needs to be logged in) to call this method.