Merge pull request #19 from arugal/feature/instancedep

add getServiceInstanceTopology
diff --git a/topology.graphqls b/topology.graphqls
index 08b3333..27b9a56 100644
--- a/topology.graphqls
+++ b/topology.graphqls
@@ -58,10 +58,12 @@
 
 
 extend type Query {
-    # Query the global topolgoy
+    # Query the global topology
     getGlobalTopology(duration: Duration!): Topology
     # Query the topology, based on the given service
     getServiceTopology(serviceId: ID!, duration: Duration!): Topology
+    # Query the instance topology, based on the given clientServiceId and serverServiceId
+    getServiceInstanceTopology(clientServiceId: ID!, serverServiceId: ID!, duration: Duration!): Topology
     # Query the topology, based on the given endpoint
     getEndpointTopology(endpointId: ID!, duration: Duration!): Topology
 }