Send cluster status while deploying

While the cluster is starting or reconfiguring during deployment and
redeployment, we'll send out periodic messages to the
`eu.nebulouscloud.optimiser.controller.app_state` channel of the
following form:

```
{
  "when": "2024-04-17T07:54:00.169580700Z",
  "state": "DEPLOYING",
  "clusterState": { ... }
}
```

If the `clusterState` key exists, its value will be the return value of
SAL's getCluster endpoint.  The value format is defined in the
sal-common class `Cluster`; see
https://github.com/ow2-proactive/scheduling-abstraction-layer/blob/master/sal-common/src/main/java/org/ow2/proactive/sal/model/Cluster.java

Note that the `clusterState` key may be missing from the status message;
this is the case when deployment or redeployment has been triggered but
the optimiser-controller is still calculating the necessary changes to
the cluster.

optimiser-controller/src/main/java/eu/nebulouscloud/optimiser/controller/ExnConnector.java

@@ -1023,4 +1023,24 @@ public void sendAppStatus(String appID, NebulousApp.State state) {
         appStatusPublisher.send(msg, appID);
     }
 
+    /**
+     * Broadcasts an application's state, with an auxiliary data value
+     * attached.<p>
+     *
+     * Messages are in the same form as sent by {@link #sendAppStatus(String,
+     * NebulousApp.State)} but with an additional {@code key: value} entry in
+     * the status message.
+     *
+     * @param appID the application id.
+     * @param state the state of the application.
+     * @param key the key of an additional entry in the status message
+     * @param value the value of an additional entry in the status message
+     */
+    public void sendAppStatus(String appID, NebulousApp.State state, String key, JsonNode value) {
+        Map<String, Object> msg = Map.of(
+            "state", state.toString(),
+            key, mapper.convertValue(value, Map.class));
+        appStatusPublisher.send(msg, appID);
+    }
+
 }

optimiser-controller/src/main/java/eu/nebulouscloud/optimiser/controller/NebulousApp.java

@@ -389,6 +389,24 @@ public boolean setStateDeploying() {
         }
     }
 
+    /**
+     * If app is in the DEPLOYING state, sends a DEPLOYING state message, with
+     * the cluster status as reported by SAL.  Otherwise does nothing.
+     *
+     * @param clusterStatus a JSON node with the cluster status returned by
+     *  the getCluster endpoint.
+     * @return true if status message sent, false otherwise.
+     */
+    @Synchronized
+    public boolean sendDeploymentStatus(JsonNode clusterState) {
+        if (state == State.DEPLOYING) {
+            exnConnector.sendAppStatus(UUID, state, "clusterState", clusterState);
+            return true;
+        } else {
+            return false;
+        }
+    }
+
     /** Set state from DEPLOYING to RUNNING and update app cluster information.
       * @return false if not in state deploying, otherwise true. */
     @Synchronized

optimiser-controller/src/main/java/eu/nebulouscloud/optimiser/controller/NebulousAppDeployer.java

@@ -290,7 +290,9 @@ public static String createNodeName(String clusterName, String componentName, in
      * @param appID The application id.
      * @param clusterName The name of the cluster to poll.
      */
-    private static boolean waitForClusterDeploymentFinished(ExnConnector conn, String appID, String clusterName) {
+    private static boolean waitForClusterDeploymentFinished(ExnConnector conn, NebulousApp app) {
+        String appID = app.getUUID();
+        String clusterName = app.getClusterName();
         final int pollInterval = 10000; // Check status every 10s
         int callsSincePrinting = 0; // number of intervals since we last logged what we're doing
         int failedCalls = 0;
@@ -310,6 +312,7 @@ private static boolean waitForClusterDeploymentFinished(ExnConnector conn, Strin
             if (clusterState != null) {
                 JsonNode jsonState = clusterState.at("/status");
                 status = jsonState.isMissingNode() ? null : jsonState.asText();
+                app.sendDeploymentStatus(clusterState);
             } else {
                 status = null;
             }
@@ -611,7 +614,7 @@ public static void deployApplication(NebulousApp app, JsonNode kubevela) {
             return;
         }
 
-        if (!waitForClusterDeploymentFinished(conn, appUUID, clusterName)) {
+        if (!waitForClusterDeploymentFinished(conn, app)) {
             log.error("Error while waiting for deployCluster to finish, trying to delete cluster {} and aborting deployment",
                 cluster);
             app.setStateFailed();
@@ -844,7 +847,9 @@ public static void redeployApplication(NebulousApp app, ObjectNode updatedKubeve
                 log.info("Starting scaleout: {}", nodesToAdd);
                 Main.logFile("redeploy-scaleout-" + appUUID + ".json", nodesToAdd.toPrettyString());
                 conn.scaleOut(appUUID, clusterName, nodesToAdd);
-                waitForClusterDeploymentFinished(conn, appUUID, clusterName);
+                // TODO: check for error and set app state failed?  (See the
+                // other call to waitForClusterDeploymentFinished)
+                waitForClusterDeploymentFinished(conn, app);
             } else {
                 log.info("No nodes added, skipping scaleout");
             }