Add application topology query type

apm-protocol/apm-ui-protocol/src/main/resources/ui-graphql/common.graphqls

@@ -0,0 +1,21 @@
+schema {
+  query: Query
+}
+
+type Query {
+  version: String
+}
+
+type Duration{
+  start: String!  # https://www.ietf.org/rfc/rfc3339.txt
+  end: String!
+  step: Step!
+}
+
+enum Step{
+  MONTH
+  DAY
+  HOUR
+  MINUTE
+  SECOND
+}

apm-protocol/apm-ui-protocol/src/main/resources/ui-graphql/overview-layer.graphqls

@@ -0,0 +1,38 @@
+type ApplicationTopology {
+  nodes: [Node]!
+  edges: [Edge]
+  duration: Duration!
+}
+
+interface Node {
+  id: ID!
+  name: String!
+  type: String
+}
+
+type ApplicationNode implements Node {
+  id: ID!
+  name: String!
+  type: String
+  sla: Float!
+  calls: Long!
+  apdex: Float!
+  totalInstance: Int!
+  totalAlert: Int!
+}
+
+type ResourceNode implements Node {
+  id: ID!
+  name: String!
+  type: String
+}
+
+type Edge {
+  source: ID!
+  target: ID!
+  isAlert: Boolean
+}
+
+extend type Query {
+  getApplicationTopology: ApplicationTopology
+}