Changed the requires file to take 'before' and 'after' parameters to declare forward and backward dependencies. Declaring 'before' will FORCE the listed module to be installed along with this one. See the docs.

client/bin/disco

@@ -47,22 +47,39 @@ function dance() {
 	exit 1
     fi
 
-    # Create the toposort of all the modules
-    for module in $(disco-param keys $(hostname)/modules)
-    do
-	NOOP="true" disco-ball fetch $module
-	disco-ball requires $module >> /tmp/$$.tsort
+    # Create the toposort of all the modules and fetch all their metadata
+    # This also includes fetching modules that aren't explicitly called out in
+    # our class list, but are required by 'before' statements in the requires files.
+    rm -f /tmp/$$.tsort
+    disco-param keys $(hostname)/modules | tac > /tmp/$$.modules.prev
+    NEWBALLS=$(cat /tmp/$$.modules.prev)
+    while [ "$NEWBALLS" != "" ]; do
+	for module in $NEWBALLS
+	do
+	    NOOP="true" disco-ball fetch $module
+	    disco-ball requires $module >> /tmp/$$.tsort
+	    cat /tmp/$$.tsort | tsort | tac > /tmp/$$.modules.new
+	done
+	NEWBALLS=$(diff /tmp/$$.modules.prev /tmp/$$.modules.new | grep "^> " | cut -d " " -f 2-)
+	cp /tmp/$$.modules.new /tmp/$$.modules.prev
+	if [ "$NEWBALLS" != "" ]; then
+	    echo "info: Discovered dependency : ${module} : $(echo -n ${NEWBALLS} | sed s/' '/', '/g)"
+	fi
     done
 
-    for module in $(cat /tmp/$$.tsort | tsort | tac)
-    do
-	disco-ball spin ${module}
-    done
+    echo "info: Ready to dance :"
+    cat /tmp/$$.tsort | tsort | tac | sed s/"^"/"info:        "/g
+
+#    for module in $(cat /tmp/$$.tsort | tsort | tac)
+#    do
+#	disco-ball spin ${module}
+#    done
 
     if [ "$REPORT" != "" ]; then
 	report
     fi
 
+    #rm -f /tmp/$$.*
 }
 
 $1 "$2" "$3" "$4" "$5" "$6" "$7" "$8" "$9"