OpenStack4j > Documentation / Multiple Threads using a single Client

General

OpenStack Services

Using the Same Client Between Threads

Many users have asked how they utilize a singleton client in their applications between multiple threads. Due to sessions being thread scoped we have listed an example allowing re-wiring of a token to instantiate a lightweight client (no re-authentication needed) in an alternate thread.

When using Identity V2:

// Grab the access from the client in the thread that did the authentication
Access access = os.getAccess();

// Spawn off a thread giving it the access
myThreadExecutor.submit(new MyRunnableOrCallable(access));

// Example of the Runnable or other object invoked in a new thread
public class MyRunnable implements Runnable {
     private OSClient clientV2;

     public MyRunnable(Access access) {
          clientV2 = OSFactory.clientFromAccess(access);
     }

    public void run() { 
        // can now use the client :)
    }
}

When using Identity V3:

// Grab the token from the client in the thread that did the authentication
Token token = os.getToken();

// Spawn off a thread giving it the access
myThreadExecutor.submit(new MyRunnableOrCallable(token));

// Example of the Runnable or other object invoked in a new thread
public class MyRunnable implements Runnable {
     private OSClientV3 clientV3;

     public MyRunnable(Access access) {
          clientV3 = OSFactory.clientFromToken(token);
     }

    public void run() {
        // can now use the client :)
    }
}