f-50: lab: arguments QEMU et seeds cloud-init des VM #50

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

cmd/lab/main.go

@@ -1,45 +1,73 @@
 package main
 
 import (
+	"flag"
 	"fmt"
 	"io"
 	"os"
+	"path/filepath"
+	"strings"
 
+	"git.g3e.fr/syonad/two/internal/lab/render"
 	"git.g3e.fr/syonad/two/internal/lab/topology"
 )
 
-const usage = `usage: lab <command> <topology.yml>
+const usage = `usage: lab <command> [options] <topology.yml> [dir]
 
-  plan    validate the topology and print the deterministic plan: addresses, cables, ports
+  plan <topology.yml>
+      validate the topology and print the deterministic plan: addresses, cables, ports
+
+  render -key <public key file> <topology.yml> <dir>
+      write, for each node, <dir>/<node>/qemu.args (one argument per line) and the
+      cloud-init seed files meta-data, user-data and network-config
 `
 
+type keyFiles []string
+
+func (k *keyFiles) String() string     { return strings.Join(*k, ",") }
+func (k *keyFiles) Set(v string) error { *k = append(*k, v); return nil }
+
 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 {
+	if len(args) == 0 {
 		fmt.Fprint(stderr, usage)
 		return 2
 	}
 	switch args[0] {
 	case "plan":
+		if len(args) != 2 {
+			fmt.Fprint(stderr, usage)
+			return 2
+		}
 		return plan(args[1], stdout, stderr)
+	case "render":
+		return renderCmd(args[1:], stdout, stderr)
 	default:
 		fmt.Fprint(stderr, usage)
 		return 2
 	}
 }
 
-func plan(path string, stdout, stderr io.Writer) int {
+func load(path string, stderr io.Writer) (*topology.Plan, bool) {
 	t, err := topology.Load(path)
 	if err != nil {
 		fmt.Fprintf(stderr, "lab: %v\n", err)
-		return 1
+		return nil, false
 	}
 	p, err := topology.Compute(t)
 	if err != nil {
 		fmt.Fprintf(stderr, "lab: %s:\n%v\n", path, err)
+		return nil, false
+	}
+	return p, true
+}
+
+func plan(path string, stdout, stderr io.Writer) int {
+	p, ok := load(path, stderr)
+	if !ok {
 		return 1
 	}
 	if err := p.Write(stdout); err != nil {
@@ -48,3 +76,82 @@ func plan(path string, stdout, stderr io.Writer) int {
 	}
 	return 0
 }
+
+func renderCmd(args []string, stdout, stderr io.Writer) int {
+	fs := flag.NewFlagSet("render", flag.ContinueOnError)
+	fs.SetOutput(stderr)
+	fs.Usage = func() { fmt.Fprint(stderr, usage) }
+	var keys keyFiles
+	fs.Var(&keys, "key", "public key file allowed to log in, repeatable")
+	if err := fs.Parse(args); err != nil {
+		return 2
+	}
+	if fs.NArg() != 2 || len(keys) == 0 {
+		fmt.Fprint(stderr, usage)
+		return 2
+	}
+
+	p, ok := load(fs.Arg(0), stderr)
+	if !ok {
+		return 1
+	}
+	dir, err := filepath.Abs(fs.Arg(1))
+	if err != nil {
+		fmt.Fprintf(stderr, "lab: %v\n", err)
+		return 1
+	}
+	authorized, err := readKeys(keys)
+	if err != nil {
+		fmt.Fprintf(stderr, "lab: %v\n", err)
+		return 1
+	}
+	nodes, err := render.Render(p, render.Options{RunDir: dir, AuthorizedKeys: authorized})
+	if err != nil {
+		fmt.Fprintf(stderr, "lab: %v\n", err)
+		return 1
+	}
+	for _, n := range nodes {
+		if err := writeNode(n); err != nil {
+			fmt.Fprintf(stderr, "lab: %v\n", err)
+			return 1
+		}
+		fmt.Fprintf(stdout, "%s\n", n.Dir)
+	}
+	return 0
+}
+
+func readKeys(files []string) ([]string, error) {
+	var keys []string
+	for _, f := range files {
+		data, err := os.ReadFile(f)
+		if err != nil {
+			return nil, err
+		}
+		for _, line := range strings.Split(string(data), "\n") {
+			line = strings.TrimSpace(line)
+			if line == "" || strings.HasPrefix(line, "#") {
+				continue
+			}
+			keys = append(keys, line)
+		}
+	}
+	return keys, nil
+}
+
+func writeNode(n render.Node) error {
+	if err := os.MkdirAll(n.Dir, 0o700); err != nil {
+		return err
+	}
+	files := map[string][]byte{
+		"qemu.args":      []byte(strings.Join(n.QEMU, "\n") + "\n"),
+		"meta-data":      n.MetaData,
+		"user-data":      n.UserData,
+		"network-config": n.NetworkConfig,
+	}
+	for name, content := range files {
+		if err := os.WriteFile(filepath.Join(n.Dir, name), content, 0o600); err != nil {
+			return err
+		}
+	}
+	return nil
+}