f-50: lab: topologie et calcul du plan #50

Signed-off-by: GnomeZworc <nicolas.boufidjeline@g3e.fr>

cmd/lab/main.go

@@ -0,0 +1,50 @@
+package main
+
+import (
+	"fmt"
+	"io"
+	"os"
+
+	"git.g3e.fr/syonad/two/internal/lab/topology"
+)
+
+const usage = `usage: lab <command> <topology.yml>
+
+  plan    validate the topology and print the deterministic plan: addresses, cables, ports
+`
+
+func main() {
+	os.Exit(run(os.Args[1:], os.Stdout, os.Stderr))
+}
+
+func run(args []string, stdout, stderr io.Writer) int {
+	if len(args) != 2 {
+		fmt.Fprint(stderr, usage)
+		return 2
+	}
+	switch args[0] {
+	case "plan":
+		return plan(args[1], stdout, stderr)
+	default:
+		fmt.Fprint(stderr, usage)
+		return 2
+	}
+}
+
+func plan(path string, stdout, stderr io.Writer) int {
+	t, err := topology.Load(path)
+	if err != nil {
+		fmt.Fprintf(stderr, "lab: %v\n", err)
+		return 1
+	}
+	p, err := topology.Compute(t)
+	if err != nil {
+		fmt.Fprintf(stderr, "lab: %s:\n%v\n", path, err)
+		return 1
+	}
+	if err := p.Write(stdout); err != nil {
+		fmt.Fprintf(stderr, "lab: %v\n", err)
+		return 1
+	}
+	return 0
+}

cmd/lab/main_test.go

@@ -0,0 +1,72 @@
+package main
+
+import (
+	"bytes"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+func runLab(args ...string) (int, string, string) {
+	var stdout, stderr bytes.Buffer
+	code := run(args, &stdout, &stderr)
+	return code, stdout.String(), stderr.String()
+}
+
+func TestRun_UsageOnMissingArguments(t *testing.T) {
+	for _, args := range [][]string{nil, {"plan"}, {"deploy", "x.yml"}, {"plan", "a.yml", "b.yml"}} {
+		code, _, stderr := runLab(args...)
+		if code != 2 || !strings.Contains(stderr, "usage: lab") {
+			t.Errorf("args %v: code %d, stderr %q", args, code, stderr)
+		}
+	}
+}
+
+func TestRun_PlanOfTheShippedExampleTopology(t *testing.T) {
+	code, stdout, stderr := runLab("plan", filepath.Join("..", "..", "conf", "lab", "evpn-2hv.yml"))
+	if code != 0 {
+		t.Fatalf("code %d, stderr %s", code, stderr)
+	}
+	for _, want := range []string{
+		"lab evpn-2hv: nodes 4, segments 1, cables 3",
+		"gateway 10.250.0.1",
+		"hv2   underlay   10.250.0.4/24  02:4c:00:03:00:00  20004  <->  sw1 p2",
+	} {
+		if !strings.Contains(stdout, want) {
+			t.Errorf("output does not contain %q:\n%s", want, stdout)
+		}
+	}
+}
+
+func TestRun_InvalidTopologyExitsWithErrors(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "bad.yml")
+	doc := `name: bad
+images:
+  deb: { url: https://example.invalid/a, sums: https://example.invalid/b }
+segments:
+  under: { switch: sw, cidr: 10.0.0.0/31 }
+nodes:
+  sw: { role: switch, image: deb, cpus: 1, memory: 512 }
+  rr: { role: router, image: deb, cpus: 1, memory: 512, segments: [under] }
+`
+	if err := os.WriteFile(path, []byte(doc), 0o600); err != nil {
+		t.Fatal(err)
+	}
+	code, stdout, stderr := runLab("plan", path)
+	if code != 1 || stdout != "" {
+		t.Fatalf("code %d, stdout %q", code, stdout)
+	}
+	for _, want := range []string{path, `role "router"`, "prefix length out of range"} {
+		if !strings.Contains(stderr, want) {
+			t.Errorf("stderr does not mention %q:\n%s", want, stderr)
+		}
+	}
+}
+
+func TestRun_MissingFile(t *testing.T) {
+	code, _, stderr := runLab("plan", filepath.Join(t.TempDir(), "absent.yml"))
+	if code != 1 || !strings.Contains(stderr, "absent.yml") {
+		t.Errorf("code %d, stderr %q", code, stderr)
+	}
+}