1 files changed, 163 insertions, 1 deletions

diff --git a/cmd/skiff/main.go b/cmd/skiff/main.go
index 33aaf5e..2fe5907 100644
--- a/cmd/skiff/main.go
+++ b/cmd/skiff/main.go
@@ -7,10 +7,14 @@ import (
 	"flag"
 	"fmt"
 	"os"
+	"sort"
 	"strings"
+	"time"
 
 	"skiff/internal/appmeta"
 	"skiff/internal/deploy"
+	"skiff/internal/envfile"
+	"skiff/internal/health"
 	"skiff/internal/jailmgr"
 	"skiff/internal/layout"
 	"skiff/internal/sh"
@@ -20,7 +24,7 @@ import (
 
 func main() {
 	if len(os.Args) < 2 {
-		fmt.Fprintln(os.Stderr, "usage: skiff <deploy|new-app|rollback> [flags]")
+		fmt.Fprintln(os.Stderr, "usage: skiff <deploy|new-app|rollback|config> [flags]")
 		os.Exit(1)
 	}
 
@@ -32,6 +36,8 @@ func main() {
 		err = cmdNewApp(os.Args[2:])
 	case "rollback":
 		err = cmdRollback(os.Args[2:])
+	case "config":
+		err = cmdConfig(os.Args[2:])
 	default:
 		fmt.Fprintf(os.Stderr, "unknown subcommand %q\n", os.Args[1])
 		os.Exit(1)
@@ -92,6 +98,9 @@ func cmdNewApp(args []string) error {
 	if err := os.MkdirAll(cfg.ReleasesDir(*name), 0755); err != nil {
 		return fmt.Errorf("create app dir: %w", err)
 	}
+	if err := envfile.Save(cfg.EnvPath(*name), map[string]string{}); err != nil {
+		return fmt.Errorf("initialize env file: %w", err)
+	}
 
 	if err := jailmgr.WriteConf(cfg, *name, *ip); err != nil {
 		return fmt.Errorf("write jail config: %w", err)
@@ -158,3 +167,156 @@ func cmdRollback(args []string) error {
 	}
 	return jailmgr.Restart(ctx, os.Stdout, *app)
 }
+
+func cmdConfig(args []string) error {
+	if len(args) < 1 {
+		return fmt.Errorf("usage: skiff config <set|unset|list> --app <name> [args...]")
+	}
+	switch args[0] {
+	case "set":
+		return cmdConfigSet(args[1:])
+	case "unset":
+		return cmdConfigUnset(args[1:])
+	case "list":
+		return cmdConfigList(args[1:])
+	default:
+		return fmt.Errorf("unknown config subcommand %q", args[0])
+	}
+}
+
+func cmdConfigSet(args []string) error {
+	fs := flag.NewFlagSet("config set", flag.ExitOnError)
+	app := fs.String("app", "", "app name")
+	// --app must precede the positional KEY=VALUE args: the flag package
+	// stops parsing flags at the first non-flag argument.
+	fs.Parse(args)
+	pairs := fs.Args()
+
+	if *app == "" {
+		return fmt.Errorf("--app is required")
+	}
+	if len(pairs) == 0 {
+		return fmt.Errorf("usage: skiff config set --app <name> KEY=VALUE [KEY=VALUE...]")
+	}
+
+	return applyConfigChange(*app, func(kv map[string]string) error {
+		for _, pair := range pairs {
+			parts := strings.SplitN(pair, "=", 2)
+			if len(parts) != 2 {
+				return fmt.Errorf("invalid KEY=VALUE pair %q", pair)
+			}
+			key := parts[0]
+			if !envfile.ValidKey(key) {
+				return fmt.Errorf("invalid env var key %q", key)
+			}
+			kv[key] = parts[1]
+		}
+		return nil
+	})
+}
+
+func cmdConfigUnset(args []string) error {
+	fs := flag.NewFlagSet("config unset", flag.ExitOnError)
+	app := fs.String("app", "", "app name")
+	// --app must precede the positional KEY args, as above.
+	fs.Parse(args)
+	keys := fs.Args()
+
+	if *app == "" {
+		return fmt.Errorf("--app is required")
+	}
+	if len(keys) == 0 {
+		return fmt.Errorf("usage: skiff config unset --app <name> KEY [KEY...]")
+	}
+
+	return applyConfigChange(*app, func(kv map[string]string) error {
+		for _, key := range keys {
+			delete(kv, key)
+		}
+		return nil
+	})
+}
+
+func cmdConfigList(args []string) error {
+	fs := flag.NewFlagSet("config list", flag.ExitOnError)
+	app := fs.String("app", "", "app name")
+	fs.Parse(args)
+
+	if *app == "" {
+		return fmt.Errorf("--app is required")
+	}
+	cfg := layout.Default()
+	if _, err := os.Stat(cfg.MetaPath(*app)); err != nil {
+		return fmt.Errorf("app %q not found: %w", *app, err)
+	}
+
+	kv, err := envfile.Load(cfg.EnvPath(*app))
+	if err != nil {
+		return fmt.Errorf("load config: %w", err)
+	}
+	keys := make([]string, 0, len(kv))
+	for key := range kv {
+		keys = append(keys, key)
+	}
+	sort.Strings(keys)
+	for _, key := range keys {
+		fmt.Printf("%s=%s\n", key, kv[key])
+	}
+	return nil
+}
+
+// applyConfigChange loads app's current env file, applies mutate to it, and
+// carries the same snapshot -> restart -> health-check -> rollback-on-
+// failure sequence deploy.Run uses for code deploys - a bad config change
+// is exactly as much of an outage as a bad deploy, guarded the same way.
+func applyConfigChange(app string, mutate func(map[string]string) error) error {
+	cfg := layout.Default()
+	if _, err := os.Stat(cfg.MetaPath(app)); err != nil {
+		return fmt.Errorf("app %q not found: %w", app, err)
+	}
+
+	kv, err := envfile.Load(cfg.EnvPath(app))
+	if err != nil {
+		return fmt.Errorf("load config: %w", err)
+	}
+	if err := mutate(kv); err != nil {
+		return err
+	}
+
+	ctx := context.Background()
+	out := os.Stdout
+	dataset := cfg.AppDataset(app)
+	tag := fmt.Sprintf("precfg-%d", time.Now().Unix())
+
+	fmt.Fprintln(out, "==> snapshotting current state")
+	if err := zfsutil.Snapshot(ctx, out, dataset, tag); err != nil {
+		return fmt.Errorf("snapshot: %w", err)
+	}
+
+	if err := envfile.Save(cfg.EnvPath(app), kv); err != nil {
+		return fmt.Errorf("save config: %w", err)
+	}
+
+	if err := jailmgr.Restart(ctx, out, app); err != nil {
+		return fmt.Errorf("restart: %w", err)
+	}
+
+	meta, err := appmeta.Read(cfg.MetaPath(app))
+	if err != nil {
+		return fmt.Errorf("read app metadata: %w", err)
+	}
+
+	if err := health.WaitHealthy(ctx, meta); err != nil {
+		fmt.Fprintf(out, "==> health check failed (%v), rolling back to %s\n", err, tag)
+		if rbErr := zfsutil.Rollback(ctx, out, dataset, tag); rbErr != nil {
+			return fmt.Errorf("health check failed AND rollback failed: %v / %w", err, rbErr)
+		}
+		if rbErr := jailmgr.Restart(ctx, out, app); rbErr != nil {
+			return fmt.Errorf("health check failed, rolled back, but restart failed: %v / %w", err, rbErr)
+		}
+		return fmt.Errorf("config change failed health check and was rolled back: %w", err)
+	}
+
+	fmt.Fprintln(out, "==> config updated")
+	return nil
+}