Metrics framework update. Mostly to make metrics work on clusters.

- Metrics now work on cluster deployments with no caveats.  It should be
  completely transparent.  Intermediate updates to speed some detection
  will come later.

scripts/base/frameworks/cluster/__load__.bro

@@ -19,7 +19,7 @@ redef peer_description = Cluster::node;
 
 @load ./setup-connections
 
-# Don't start the listening process until we're a bit more sure that the
+# Don't load the listening script until we're a bit more sure that the
 # cluster framework is actually being enabled.
 @load frameworks/communication/listen-clear
 

scripts/base/frameworks/cluster/main.bro

@@ -47,6 +47,25 @@ export {
 		time_machine: string      &optional;
 	};
 	
+	## This function can be called at any time to determine if the cluster
+	## framework is being enabled for this run.
+	global is_enabled: function(): bool;
+	
+	## This function can be called at any time to determine what type of
+	## cluster node the current Bro instance is going to be acting as.
+	## :bro:id:`is_enabled` should be called first to find out if this is
+	## actually going to be a cluster node.
+	global local_node_type: function(): NodeType;
+	
+	## This gives the value for the number of workers currently connected to,
+	## and it's maintained internally by the cluster framework.  It's 
+	## primarily intended for use by managers to find out how many workers 
+	## should be responding to requests.
+	global worker_count: count = 0;
+	
+	## The cluster layout definition.  This should be placed into a filter
+	## named cluster-layout.bro somewhere in the BROPATH.  It will be 
+	## automatically loaded if the CLUSTER_NODE environment variable is set.
 	const nodes: table[string] of Node = {} &redef;
 	
 	## This is usually supplied on the command line for each instance
@@ -54,7 +73,29 @@ export {
 	const node = getenv("CLUSTER_NODE") &redef;
 }
 
-event bro_init()
+function is_enabled(): bool
+	{
+	return (node != "");
+	}
+
+function local_node_type(): NodeType
+	{
+	return nodes[node]$node_type;
+	}
+	
+
+event remote_connection_handshake_done(p: event_peer)
+	{
+	if ( nodes[p$descr]$node_type == WORKER )
+		++worker_count;
+	}
+event remote_connection_closed(p: event_peer)
+	{
+	if ( nodes[p$descr]$node_type == WORKER )
+		--worker_count;
+	}
+
+event bro_init() &priority=5
 	{
 	# If a node is given, but it's an unknown name we need to fail.
 	if ( node != "" && node !in nodes )

scripts/base/frameworks/cluster/setup-connections.bro

@@ -60,13 +60,12 @@ event bro_init() &priority=9
 				                                   $connect=T, $retry=1mins, 
 				                                   $class=node];
 			}
-		
 		else if ( me$node_type == WORKER )
 			{
 			if ( n$node_type == MANAGER && me$manager == i )
 				Communication::nodes["manager"] = [$host=nodes[i]$ip, $p=nodes[i]$p,
 				                                   $connect=T, $retry=1mins, 
-				                                   $class=node];
+				                                   $class=node, $events=manager_events];
 			
 			if ( n$node_type == PROXY && me$proxy == i )
 				Communication::nodes["proxy"] = [$host=nodes[i]$ip, $p=nodes[i]$p,