JarCastingOVSDB Client Library
Overview
This is a schema-independent OVSDB client implementation of OVSDB Management Protocol (RFC 7047). All RPC methods defined in the protocol are implemented.
Getting Started
Dependency
In order to use this library you have to add a dependency to the pom file:
<dependencies>
<dependency>
<groupId>com.vmware.ovsdb</groupId>
<artifactId>ovsdb-client</artifactId>
<version>LATEST</version>
</dependency>
</dependencies>
Passive Connection
When the OVSDB client uses passive connection mode, it implies that the OVSDB server is running on active connection mode. In other words, the client listens on certain port (6640 by default) and waits for the server to connects. For more information, see ovsdb-server(1)
In the following example, the ovsdb-server is started by command:
$ ovsdb-server --remote=tcp:192.168.201.4:6640
Note: You can also configure it to read connection methods from a db table. For example, the manager table in hardware_vtep database.
ScheduledExecutorService executorService = Executors.newSingleThreadScheduledExecutor();
OvsdbPassiveConnectionListener listener = new OvsdbPassiveConnectionListenerImpl(executorService); // (1)
CompletableFuture<OvsdbClient> ovsdbClientFuture = new CompletableFuture<>();
ConnectionCallback connectionCallback = new ConnectionCallback() { // (2)
public void connected(OvsdbClient ovsdbClient) {
System.out.println(ovsdbClient + " connected");
ovsdbClientFuture.complete(ovsdbClient);
}
public void disconnected(OvsdbClient ovsdbClient) {
System.out.println(ovsdbClient + " disconnected");
}
};
listener.startListening(6640, connectionCallback).join(); // (3)
OvsdbClient ovsdbClient = ovsdbClientFuture.get(3, TimeUnit.SECONDS); // (4)
CompletableFuture<String[]> f = ovsdbClient.listDatabases();
String[] dbs = f.get(3, TimeUnit.SECONDS);
System.out.println(Arrays.toString(dbs));
From above example we can see the steps of getting an OvsdbClient object from a passive connection.
(1) Construct a OvsdbPassiveConnectionListener. The OvsdbPassiveConnectionListenerImpl takes a ScheduledExecutorService for asynchronous operations.
(2) Implement the ConnectionCallback interface and construct a callback object.
(3) Start listening on the port.
(4) Get the OvsdbClient object from the callback and use it for operations on the OVSDB server.
Note:
- All the interfaces provided by
OvsdbClientare asynchronous and return aCompletableFuture. See OvsdbClient.java. - Exception handling is omitted in this example.
Active Connection
When the OVSDB client uses active connection mode, it implies that the OVSDB server is running on passive connection mode. In other words, the server listens on certain port (6640 by default) and waits for the client to connects. For more information, see ovsdb-server(1)
In the following example, the ovsdb-server is started by command:
$ ovsdb-server --remote=ptcp:6640
ScheduledExecutorService executorService = Executors.newSingleThreadScheduledExecutor();
OvsdbActiveConnectionConnector connector = new OvsdbActiveConnectionConnectorImpl(executorService); // (1)
CompletableFuture<OvsdbClient> ovsdbClientFuture = connector.connect("192.168.33.74", 6640); // (2)
OvsdbClient ovsdbClient = ovsdbClientFuture.get(3, TimeUnit.SECONDS); // (3)
CompletableFuture<String[]> f = ovsdbClient.listDatabases();
String[] dbs = f.get(3, TimeUnit.SECONDS);
System.out.println(Arrays.toString(dbs));
From above example we can see the steps of getting an OvsdbClient object from an active connection.
(1) Construct a OvsdbActiveConnectionConnector. The OvsdbActiveConnectionConnectorImpl takes a ScheduledExecutorService for asynchronous operations.
(2) Connect to the host:port and get a CompletableFuture<OvsdbClient>.
(3) Get the OvsdbClient object from the CompletableFuture<OvsdbClient>.
Documentation
For detailed documentation, see Wiki.
Contributing
The ovsdb-client-library project team welcomes contributions from the community. Before you start working with ovsdb-client-library, please read our Developer Certificate of Origin. All contributions to this repository must be signed as described on that page. Your signature certifies that you wrote the patch or have the right to pass it on as an open-source patch. For more detailed information, refer to CONTRIBUTING.md.
