Package com.launchdarkly.sdk.server.subsystems

Interface DataSourceUpdateSink

public interface DataSourceUpdateSink

Interface that a data source implementation will use to push data into the SDK.

The data source interacts with this object, rather than manipulating the data store directly, so that the SDK can perform any other necessary operations that must happen when data is updated.

Since:

5.0.0

See Also:

ClientContext.getDataSourceUpdateSink()

Method Summary

Modifier and Type	Method	Description
DataStoreStatusProvider	getDataStoreStatusProvider()	Returns an object that provides status tracking for the data store, if applicable.
boolean	init(DataStoreTypes.FullDataSet<DataStoreTypes.ItemDescriptor> allData)	Completely overwrites the current contents of the data store with a set of items for each collection.
void	updateStatus(DataSourceStatusProvider.State newState, DataSourceStatusProvider.ErrorInfo newError)	Informs the SDK of a change in the data source's status.
boolean	upsert(DataStoreTypes.DataKind kind, java.lang.String key, DataStoreTypes.ItemDescriptor item)	Updates or inserts an item in the specified collection.

Method Detail

init

boolean init(DataStoreTypes.FullDataSet<DataStoreTypes.ItemDescriptor> allData)

Completely overwrites the current contents of the data store with a set of items for each collection.

If the underlying data store throws an error during this operation, the SDK will catch it, log it, and set the data source state to DataSourceStatusProvider.State.INTERRUPTED with an error of DataSourceStatusProvider.ErrorKind.STORE_ERROR. It will not rethrow the error to the data source, but will simply return false to indicate that the operation failed.

Parameters:

allData - a list of DataStoreTypes.DataKind instances and their corresponding data sets

Returns:

true if the update succeeded, false if it failed

upsert

boolean upsert(DataStoreTypes.DataKind kind,
               java.lang.String key,
               DataStoreTypes.ItemDescriptor item)

Updates or inserts an item in the specified collection. For updates, the object will only be updated if the existing version is less than the new version.

To mark an item as deleted, pass an DataStoreTypes.ItemDescriptor that contains a null, with a version number (you may use DataStoreTypes.ItemDescriptor.deletedItem(int)). Deletions must be versioned so that they do not overwrite a later update in case updates are received out of order.

If the underlying data store throws an error during this operation, the SDK will catch it, log it, and set the data source state to DataSourceStatusProvider.State.INTERRUPTED with an error of DataSourceStatusProvider.ErrorKind.STORE_ERROR. It will not rethrow the error to the data source, but will simply return false to indicate that the operation failed.

Parameters:

kind - specifies which collection to use

key - the unique key for the item within that collection

item - the item to insert or update

Returns:

true if the update succeeded, false if it failed

getDataStoreStatusProvider

DataStoreStatusProvider getDataStoreStatusProvider()

Returns an object that provides status tracking for the data store, if applicable.

This may be useful if the data source needs to be aware of storage problems that might require it to take some special action: for instance, if a database outage may have caused some data to be lost and therefore the data should be re-requested from LaunchDarkly.

Returns:

a DataStoreStatusProvider

updateStatus

void updateStatus(DataSourceStatusProvider.State newState,
                  DataSourceStatusProvider.ErrorInfo newError)

Informs the SDK of a change in the data source's status.

Data source implementations should use this method if they have any concept of being in a valid state, a temporarily disconnected state, or a permanently stopped state.

If newState is different from the previous state, and/or newError is non-null, the SDK will start returning the new status (adding a timestamp for the change) from DataSourceStatusProvider.getStatus(), and will trigger status change events to any registered listeners.

A special case is that if newState is DataSourceStatusProvider.State.INTERRUPTED, but the previous state was DataSourceStatusProvider.State.INITIALIZING, the state will remain at DataSourceStatusProvider.State.INITIALIZING because DataSourceStatusProvider.State.INTERRUPTED is only meaningful after a successful startup.

Parameters:

newState - the data source state

newError - information about a new error, if any

See Also:

DataSourceStatusProvider