io.spine.web.firebase.rest

Class RemoteDatabaseClient

java.lang.Object

io.spine.web.firebase.rest.RemoteDatabaseClient

All Implemented Interfaces:

FirebaseClient

public final class RemoteDatabaseClient
extends java.lang.Object
implements FirebaseClient

A FirebaseClient which operates via the Firebase REST API and the Java Admin SDK.

The client uses the Java Firebase Admin SDK for subscribing to events of a given database node. The API exposes the ChildEventListener so that the caller may build more complex "nested" subscriptions without a need to re-fetch database references.

For all the other operations, the client uses the Firebase REST API as described in the documentation.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	RemoteDatabaseClient.Builder A builder for the RemoteDatabaseClient instances.

Method Summary

Modifier and Type	Method and Description
void	create(io.spine.web.firebase.NodePath nodePath, NodeValue value) Writes the specified value to the Firebase database node.
void	delete(io.spine.web.firebase.NodePath nodePath) Deletes the node under the given path.
java.util.Optional<NodeValue>	fetchNode(io.spine.web.firebase.NodePath nodePath) Retrieves the value of the specified Firebase database node.
static RemoteDatabaseClient.Builder	newBuilder() Creates a new instance of Builder for RemoteDatabaseClient instances.
void	subscribeTo(io.spine.web.firebase.NodePath nodePath, com.google.firebase.database.ChildEventListener listener) Subscribes to the child events of the given node.
void	update(io.spine.web.firebase.NodePath nodePath, NodeValue value) Merges the specified value to the Firebase database node.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

fetchNode

public java.util.Optional<NodeValue> fetchNode(io.spine.web.firebase.NodePath nodePath)

Description copied from interface: FirebaseClient

Retrieves the value of the specified Firebase database node.

The null value (i.e. the node is not present in the database) is returned as Optional.empty().

Specified by:

fetchNode in interface FirebaseClient

Parameters:

nodePath - the path to the requested node in the database

Returns:

the node value or empty Optional if the node is not present in the database

subscribeTo

public void subscribeTo(io.spine.web.firebase.NodePath nodePath,
                        com.google.firebase.database.ChildEventListener listener)

Description copied from interface: FirebaseClient

Subscribes to the child events of the given node.

Specified by:

subscribeTo in interface FirebaseClient

Parameters:

nodePath - the path to the node to subscribe to

listener - the callbacks invoked on child events

create

public void create(io.spine.web.firebase.NodePath nodePath,
                   NodeValue value)

Description copied from interface: FirebaseClient

Writes the specified value to the Firebase database node.

If the node exists, the value is overridden.

Specified by:

create in interface FirebaseClient

Parameters:

nodePath - the path to the node in the Firebase database

value - the value to write

update

public void update(io.spine.web.firebase.NodePath nodePath,
                   NodeValue value)

Description copied from interface: FirebaseClient

Merges the specified value to the Firebase database node.

If the node doesn't exist, it is created with the given value.

If the node exists, the value entries are added to the node children overwriting common ones if present.

Specified by:

update in interface FirebaseClient

Parameters:

nodePath - the path to the node in the Firebase database

value - the value to merge

delete

public void delete(io.spine.web.firebase.NodePath nodePath)

Description copied from interface: FirebaseClient

Deletes the node under the given path.

Does nothing if the node does not exist.

Specified by:

delete in interface FirebaseClient

Parameters:

nodePath - the path to the node to delete

newBuilder

public static RemoteDatabaseClient.Builder newBuilder()

Creates a new instance of Builder for RemoteDatabaseClient instances.

Returns:

new instance of Builder