add file i had forgotten to

diagnostics/vis.go

+package diagnostics
+
+import "encoding/json"
+
+type node struct {
+	Name  string `json:"name"`
+	Value uint64 `json:"value"`
+}
+
+type link struct {
+	Source int `json:"source"`
+	Target int `json:"target"`
+	Value  int `json:"value"`
+}
+
+func GetGraphJson(dinfo []*DiagInfo) []byte {
+	out := make(map[string]interface{})
+	names := make(map[string]int)
+	var nodes []*node
+	for _, di := range dinfo {
+		names[di.ID] = len(nodes)
+		val := di.BwIn + di.BwOut
+		nodes = append(nodes, &node{Name: di.ID, Value: val})
+	}
+
+	var links []*link
+	linkexists := make([][]bool, len(nodes))
+	for i, _ := range linkexists {
+		linkexists[i] = make([]bool, len(nodes))
+	}
+
+	for _, di := range dinfo {
+		myid := names[di.ID]
+		for _, con := range di.Connections {
+			thisid := names[con.ID]
+			if !linkexists[thisid][myid] {
+				links = append(links, &link{
+					Source: myid,
+					Target: thisid,
+					Value:  3,
+				})
+				linkexists[myid][thisid] = true
+			}
+		}
+	}
+
+	out["nodes"] = nodes
+	out["links"] = links
+
+	b, err := json.Marshal(out)
+	if err != nil {
+		panic(err)
+	}
+
+	return b
+}