SharedStateCollection

SharedStateCollection

The SharedStateCollection interface represent a collection of all states created from a given class name on the network.

It can optionally exclude the states created by the current node.

See ClientStateManager#getCollection and ServerStateManager#getCollection for factory methods API

const collection = await client.stateManager.getCollection('my-class');
const allValues = collection.getValues();
collection.onUpdate((state, newValues, oldValues) => {
  // do something
});

Members

className :String

Description:

  • Name of the class from which the collection has been created.

Source:

Name of the class from which the collection has been created.

Type:
  • String

(readonly) length :number

Description:

  • Size of the collection, alias size

Source:

Size of the collection, alias size

Type:
  • number

schemaName

Source:
Deprecated:

size :number

Description:

  • Size of the collection, , alias length

Source:

Size of the collection, , alias length

Type:
  • number

Methods

(async) detach()

Description:

  • Detach from the collection, i.e. detach all underlying shared states.

Source:

filter(func)

Description:

  • Creates a shallow copy of a portion of the collection, filtered down to just the estates that pass the test implemented by the provided function (see Array.filter).

Source:
Parameters:
Name Type Description
func function

A function to execute for each element in the array. It should return a truthy to keep the element in the resulting array, and a falsy value otherwise.

find(func)

Description:

  • Returns the first element of the collection that satisfies the provided testing function. If no values satisfy the testing function, undefined is returned.

Source:
Parameters:
Name Type Description
func function

Function to execute for each element in the array. It should return a truthy value to indicate a matching element has been found.
Returns:

forEach(func)

Description:

  • Execute the given function once for each states of the collection (see Array.forEach).

Source:
Parameters:
Name Type Description
func function

A function to execute for each element in the array. Its return value is discarded.

get(name) → {Array.<any>}

Description:

  • Return the current param value of all the states in the collection.

Source:
Parameters:
Name Type Description
name String

Name of the parameter
Returns:
Type
Array.<any>

getDefaults() → {object}

Description:

  • Get the default values as declared in the class description.

Source:
Example
const defaults = state.getDefaults();
Returns:
Type
object

getDescription(paramNameopt) → {SharedStateClassDescription|SharedStateParameterDescription}

Description:
Source:
Example
const classDescription = collection.getDescription();
const paramDescription = collection.getDescription('my-param');
Parameters:
Name Type Attributes Default Description
paramName string <optional>
 null

If defined, returns the parameter description of the given parameter name rather than the full class description.
Throws:

Throws if paramName is not null and does not exists.

Returns:
Type
SharedStateClassDescription | SharedStateParameterDescription

getSchema()

Source:
Deprecated:

getUnsafe(name) → {Array.<any>}

Description:

  • Similar to get but returns a reference to the underlying value in case of any type. May be useful if the underlying value is big (e.g. sensors recordings, etc.) and deep cloning expensive. Be aware that if changes are made on the returned object, the state of your application will become inconsistent.

Source:
Parameters:
Name Type Description
name String

Name of the parameter
Returns:
Type
Array.<any>

getValues() → {Array.<Object>}

Description:

  • Return the current values of all the states in the collection.

Source:
Returns:
Type
Array.<Object>

getValuesUnsafe() → {Array.<Object>}

Description:

  • Return the current values of all the states in the collection.

    Similar to getValues but returns a reference to the underlying value in case of any type. May be useful if the underlying value is big (e.g. sensors recordings, etc.) and deep cloning expensive. Be aware that if changes are made on the returned object, the state of your application will become inconsistent.

Source:
Returns:
Type
Array.<Object>

map(func)

Description:

  • Creates a new array populated with the results of calling a provided function on every state of the collection (see Array.map).

Source:
Parameters:
Name Type Description
func function

A function to execute for each element in the array. Its return value is added as a single element in the new array.

onAttach(callback, executeListener) → {sharedStateCollectionDeleteOnAttachCallback}

Description:

  • Register a function to execute when a shared state is attached to the collection, i.e. when a node creates a new state from same SharedState class.

Source:
Parameters:
Name Type Default Description
callback sharedStateCollectionOnAttachCallback

callback to execute when a state is added to the collection.
executeListener boolean false

execute the callback with the states already present in the collection.
Returns:
  • Function that delete the registered listener when executed.
Type
sharedStateCollectionDeleteOnAttachCallback

onChange(callback) → {sharedStateCollectionDeleteOnChangeCallback}

Description:

  • Register a function to execute when any state of the collection is either attached, removed, or updated.

Source:
Example
const collection = await client.stateManager.getCollection('player');
collection.onChange(() => renderApp(), true);
Parameters:
Name Type Description
callback sharedStateCollectionOnChangeCallback

callback to execute when any state of the collection is either attached, updated, or detached.
Returns:
  • Function that delete the registered listener when executed.
Type
sharedStateCollectionDeleteOnChangeCallback

onDetach(callback) → {sharedStateCollectionDeleteOnDetachCallback}

Description:

  • Register a function to execute when a shared state is removed from the collection, i.e. when it is deleted by its owner.

Source:
Parameters:
Name Type Description
callback sharedStateCollectionOnDetachCallback

callback to execute when a state is removed from the collection.
Returns:
  • Function that delete the registered listener when executed.
Type
sharedStateCollectionDeleteOnDetachCallback

onUpdate(callback, executeListeneropt) → {sharedStateCollectionDeleteOnUpdateCallback}

Description:

  • Register a function to execute when any shared state of the collection is updated.

Source:
Parameters:
Name Type Attributes Default Description
callback sharedStateCollectionOnUpdateCallback

Callback to execute when an update is applied on a state.
executeListener Boolean <optional>
 false

Execute the callback immediately with current state values. Note that oldValues will be set to {}.
Returns:
  • Function that delete the registered listener when executed.
Type
sharedStateCollectionDeleteOnUpdateCallback

reduce(func, initialValue) → {T}

Description:

  • Execute a user-supplied "reducer" callback function on each element of the collection, in order, passing in the return value from the calculation on the preceding element. The final result of running the reducer across all elements of the array is a single value.

Source:
Parameters:
Name Type Description
func function

A function to execute for each element in the array. Its return value becomes the value of the accumulator parameter on the next invocation of callbackFn. For the last invocation, the return value becomes the return value of reduce(). The function is called with the following arguments:
initialValue T

A value to which accumulator is initialized the first time the callback is called. If initialValue is specified, callbackFn starts executing with the first value in the array as currentValue.
Returns:
Type
T

(async) set(updates) → {Promise.<Array.<Object>>}

Description:

  • Update all states of the collection with given values.

    The returned Promise resolves on a list of objects that contains the applied updates, and resolves after all the onUpdate callbacks have resolved themselves

    Alternative signatures:

    • await collection.set(updates)
    • await collection.set(name, value)
Source:
Example
const collection = await client.stateManager.getCollection('globals');
const updates = await collection.set({ myParam: Math.random() });
Parameters:
Name Type Description
updates object

key / value pairs of updates to apply to the collection.
Returns:
  • Promise to the list of (coerced) updates.
Type
Promise.<Array.<Object>>

sort(func)

Description:

  • Sort the elements of the collection in place (see Array.sort).

Source:
Parameters:
Name Type Description
func function

Function that defines the sort order.