sys.storage
This package contains methods to work with the storage. The storage is a temporary key-value data structure you can use to save information for things that span multiple user requests or threads.
It is a temporary data structure because when the app is restarted information could be lost, so you shouldn’t rely on data being available between restarts or upgrades of the app.
get(key)
Returns the value stored at the given key.
Parameters
| Name | Type | Required | Default | Description |
|---|---|---|---|---|
key |
|
yes |
The key of the value to retrieve. |
Returns
any - The value at the given key or null if there isn’t any value.
Samples
// puts something in the storage and retrives it
sys.storage.put('key1', 'a');
log('key1: '+sys.storage.get('key1'));
put(key, value, options)
Stores an object or primitive value in the storage.
Parameters
| Name | Type | Required | Default | Description |
|---|---|---|---|---|
key |
|
yes |
The key used to store the value. |
|
value |
|
yes |
The value to store. It could be a primitive or an object. |
|
options |
|
no |
Additional options for setting the value. So far the only option is |
Returns
any - The previous value associated with the given key or null if there wasn’t a value associated to it.
Samples
// puts a string and an object in the storage
sys.storage.put('key1', 'a');
log('key1: '+sys.storage.get('key1'));
var obj = {prop1: 'a', prop2: 'b'};
sys.storage.put('key2', obj);
log('key2: '+JSON.stringify(sys.storage.get('key2')));
// puts a key that will live for 1 hours
sys.storage.put('key1', 'a', {ttl: 60 * 60 * 1000});
putIfAbsent(key, value, options)
Stores an object or primitive value in the storage at the given key if it hasn’t been set already.
Parameters
| Name | Type | Required | Default | Description |
|---|---|---|---|---|
key |
|
yes |
The key used to store the value. |
|
value |
|
yes |
The value to store. It could be a primitive or an object. |
|
options |
|
no |
Additional options for setting the value. So far the only option is |
Returns
boolean - true if the value was effectively set or false otherwise.
Samples
// puts a value twice over the same key, but second time it shouldn't be stored
sys.storage.put('key1', 'a');
sys.storage.putIfAbsent('key1', 'b');
log('key1: '+sys.storage.get('key1'));
replace(key, value, options)
Replaces the value at the given key. If no value was set at that key, the new value won’t be stored.
Parameters
| Name | Type | Required | Default | Description |
|---|---|---|---|---|
key |
|
yes |
The key used to store the value. |
|
value |
|
yes |
The value to store. It could be a primitive or an object. |
|
options |
|
no |
Additional options for setting the value. So far the only option is |
Returns
boolean - true if the value was effectively set or false otherwise.
Samples
// tries to replace the value in two different keys
sys.storage.put('key1', 'a');
sys.storage.replace('key1', 'b');
sys.storage.replace('keyThatDoesNotExist', 'c');
log('key1: '+sys.storage.get('key1'));
log('keyThatDoesNotExist: '+sys.storage.get('keyThatDoesNotExist'));
remove(key)
Removes the value at the given key.
Parameters
| Name | Type | Required | Default | Description |
|---|---|---|---|---|
key |
|
yes |
The key of the value to remove. |
Returns
any - The value at the given key or null if there isn’t any value.
Samples
// puts and remove a value
sys.storage.put('key1', 'a');
log('key1: '+sys.storage.get('key1'));
sys.storage.remove('key1');
log('key1: '+sys.storage.get('key1'));
clear()
Removes all values in the storage.
Samples
// puts and remove a value
sys.storage.put('key1', 'a');
sys.storage.put('key2', 'b');
log('key1: '+sys.storage.get('key1'));
log('key2: '+sys.storage.get('key2'));
sys.storage.clear();
log('key1: '+sys.storage.get('key1'));
log('key2: '+sys.storage.get('key2'));