1 files changed, 102 insertions, 0 deletions
diff --git a/framework/src/onos/apps/metrics/src/main/java/org/onosproject/metrics/topology/cli/TopologyEventsListCommand.java b/framework/src/onos/apps/metrics/src/main/java/org/onosproject/metrics/topology/cli/TopologyEventsListCommand.java
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--- /dev/null
+++ b/framework/src/onos/apps/metrics/src/main/java/org/onosproject/metrics/topology/cli/TopologyEventsListCommand.java
@@ -0,0 +1,102 @@
+/*
+ * Copyright 2014-2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.metrics.topology.cli;
+
+import java.util.List;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.node.ArrayNode;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import org.apache.karaf.shell.commands.Command;
+import org.onosproject.cli.AbstractShellCommand;
+import org.onosproject.event.Event;
+import org.onosproject.metrics.topology.TopologyMetricsService;
+import org.onosproject.net.topology.TopologyEvent;
+
+/**
+ * Command to show the list of last topology events.
+ */
+@Command(scope = "onos", name = "topology-events",
+         description = "Lists the last topology events")
+public class TopologyEventsListCommand extends AbstractShellCommand {
+
+    private static final String FORMAT_EVENT =  "Event=%s";
+    private static final String FORMAT_REASON = "    Reason=%s";
+
+    @Override
+    protected void execute() {
+        TopologyMetricsService service = get(TopologyMetricsService.class);
+
+        if (outputJson()) {
+            print("%s", json(service.getEvents()));
+        } else {
+            for (Event event : service.getEvents()) {
+                print(FORMAT_EVENT, event);
+                if (event instanceof TopologyEvent) {
+                    TopologyEvent topologyEvent = (TopologyEvent) event;
+                    for (Event reason : topologyEvent.reasons()) {
+                        print(FORMAT_REASON, reason);
+                    }
+                }
+                print("");          // Extra empty line for clarity
+            }
+        }
+    }
+
+    /**
+     * Produces a JSON array of topology events.
+     *
+     * @param events the topology events with the data
+     * @return JSON array with the topology events
+     */
+    private JsonNode json(List<Event> events) {
+        ObjectMapper mapper = new ObjectMapper();
+        ArrayNode result = mapper.createArrayNode();
+
+        for (Event event : events) {
+            result.add(json(mapper, event));
+        }
+        return result;
+    }
+
+    /**
+     * Produces JSON object for a topology event.
+     *
+     * @param mapper the JSON object mapper to use
+     * @param event the topology event with the data
+     * @return JSON object for the topology event
+     */
+    private ObjectNode json(ObjectMapper mapper, Event event) {
+        ObjectNode result = mapper.createObjectNode();
+
+        result.put("time", event.time())
+            .put("type", event.type().toString())
+            .put("event", event.toString());
+
+        // Add the reasons if a TopologyEvent
+        if (event instanceof TopologyEvent) {
+            TopologyEvent topologyEvent = (TopologyEvent) event;
+            ArrayNode reasons = mapper.createArrayNode();
+            for (Event reason : topologyEvent.reasons()) {
+                reasons.add(json(mapper, reason));
+            }
+            result.set("reasons", reasons);
+        }
+
+        return result;
+    }
+}