kilo/pkg/mesh/graph.go
2019-05-07 16:36:02 +02:00

123 lines
4.0 KiB
Go

// Copyright 2019 the Kilo authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package mesh
import (
"fmt"
"net"
"github.com/awalterschulze/gographviz"
)
// Dot generates a Graphviz graph of the Topology in DOT fomat.
func (t *Topology) Dot() (string, error) {
g := gographviz.NewGraph()
g.Name = "kilo"
if err := g.AddAttr("kilo", string(gographviz.Label), graphEscape(t.subnet.String())); err != nil {
return "", fmt.Errorf("failed to add label to graph")
}
if err := g.AddAttr("kilo", string(gographviz.LabelLOC), "t"); err != nil {
return "", fmt.Errorf("failed to add label location to graph")
}
if err := g.AddAttr("kilo", string(gographviz.OutputOrder), "nodesfirst"); err != nil {
return "", fmt.Errorf("failed to set output ordering")
}
if err := g.AddAttr("kilo", string(gographviz.Overlap), "false"); err != nil {
return "", fmt.Errorf("failed to disable graph overlap")
}
if err := g.SetDir(true); err != nil {
return "", fmt.Errorf("failed to set direction")
}
leaders := make([]string, len(t.segments))
nodeAttrs := map[string]string{
string(gographviz.Shape): "ellipse",
}
for i, s := range t.segments {
if err := g.AddSubGraph("kilo", subGraphName(s.location), nil); err != nil {
return "", fmt.Errorf("failed to add subgraph")
}
if err := g.AddAttr(subGraphName(s.location), string(gographviz.Label), graphEscape(s.location)); err != nil {
return "", fmt.Errorf("failed to add label to subgraph")
}
if err := g.AddAttr(subGraphName(s.location), string(gographviz.Style), `"dashed,rounded"`); err != nil {
return "", fmt.Errorf("failed to add style to subgraph")
}
for j := range s.cidrs {
if err := g.AddNode(subGraphName(s.location), graphEscape(s.hostnames[j]), nodeAttrs); err != nil {
return "", fmt.Errorf("failed to add node to subgraph")
}
var wg net.IP
if j == s.leader {
wg = s.wireGuardIP
if err := g.Nodes.Lookup[graphEscape(s.hostnames[j])].Attrs.Add(string(gographviz.Rank), "1"); err != nil {
return "", fmt.Errorf("failed to add rank to node")
}
}
if err := g.Nodes.Lookup[graphEscape(s.hostnames[j])].Attrs.Add(string(gographviz.Label), nodeLabel(s.location, s.hostnames[j], s.cidrs[j], s.privateIPs[j], wg)); err != nil {
return "", fmt.Errorf("failed to add label to node")
}
}
meshSubGraph(g, g.Relations.SortedChildren(subGraphName(s.location)), s.leader, nil)
leaders[i] = graphEscape(s.hostnames[s.leader])
}
meshGraph(g, leaders, nil)
return g.String(), nil
}
func meshGraph(g *gographviz.Graph, nodes []string, attrs gographviz.Attrs) {
if attrs == nil {
attrs = make(gographviz.Attrs)
attrs[gographviz.Dir] = "both"
}
for i := range nodes {
for j := i + 1; j < len(nodes); j++ {
if i == j {
continue
}
g.Edges.Add(&gographviz.Edge{Src: nodes[i], Dst: nodes[j], Dir: true, Attrs: attrs})
}
}
}
func meshSubGraph(g *gographviz.Graph, nodes []string, leader int, attrs gographviz.Attrs) {
if attrs == nil {
attrs = make(gographviz.Attrs)
attrs[gographviz.Dir] = "both"
}
for i := range nodes {
if i == leader {
continue
}
g.Edges.Add(&gographviz.Edge{Src: nodes[leader], Dst: nodes[i], Dir: true, Attrs: attrs})
}
}
func graphEscape(s string) string {
return fmt.Sprintf("\"%s\"", s)
}
func subGraphName(name string) string {
return graphEscape(fmt.Sprintf("cluster_%s", name))
}
func nodeLabel(location, name string, cidr *net.IPNet, priv, wgIP net.IP) string {
var wg string
if wgIP != nil {
wg = wgIP.String()
}
return graphEscape(fmt.Sprintf("%s\n%s\n%s\n%s\n%s", location, name, cidr.String(), priv.String(), wg))
}