feat(caddy): make cluster storage for Caddy default, remember 'uc caddy deploy' options

cmd/uc/caddy/deploy.go

@@ -16,6 +16,7 @@ import (
 	"github.com/psviderski/uncloud/internal/cli"
 	"github.com/psviderski/uncloud/internal/cli/completion"
 	"github.com/psviderski/uncloud/internal/cli/tui"
+	"github.com/psviderski/uncloud/internal/version"
 	"github.com/psviderski/uncloud/pkg/api"
 	"github.com/psviderski/uncloud/pkg/client"
 	"github.com/spf13/cobra"
@@ -25,6 +26,10 @@ type deployOptions struct {
 	caddyfile string
 	image     string
 	machines  []string
+
+	caddyfileChanged bool
+	imageChanged     bool
+	machinesChanged  bool
 }
 
 func NewDeployCommand() *cobra.Command {
@@ -33,21 +38,62 @@ func NewDeployCommand() *cobra.Command {
 	cmd := &cobra.Command{
 		Use:   "deploy",
 		Short: "Deploy or upgrade Caddy reverse proxy across all machines in the cluster.",
-		Long: "Deploy or upgrade Caddy reverse proxy across all machines in the cluster.\n" +
-			"A rolling update is performed when updating existing containers to minimise disruption.",
+		Long: `Deploy or upgrade Caddy reverse proxy across all machines in the cluster.
+A rolling update is performed when updating existing containers to minimise disruption.
+
+By default, this deploys the latest version of the Uncloud Caddy image with a global config that enables cluster
+storage for TLS certificates. See https://github.com/unlabs-dev/caddy-uncloud for more details.
+
+Values set with --image, --caddyfile, and --machine are kept for later deployments. Pass an empty value to reset
+a flag to its default.
+
+If this command didn't deploy the current caddy service, for example, it was deployed with 'uc deploy'
+from a Compose file or an older version of uc, the deployment replaces its configuration.
+
+Requires Uncloud daemon ` + client.MinCaddyDaemonVersion + ` or newer on all machines.`,
+		Example: `  # Deploy Caddy or upgrade it to the latest version of the Uncloud Caddy image.
+  uc caddy deploy
+
+  # Deploy a custom image and keep it for later deployments.
+  uc caddy deploy --image ghcr.io/unlabs-dev/caddy-uncloud:0.1.3
+
+  # Go back to the latest version of the Uncloud Caddy image.
+  uc caddy deploy --image ""
+
+  # Deploy a custom image build and a custom global Caddy config and keep both for later deployments.
+  uc caddy deploy --image myorg/caddy-uncloud:latest --caddyfile global.Caddyfile
+
+  # Go back to the default global Caddy config but keep the custom image.
+  uc caddy deploy --caddyfile ""
+
+  # Deploy only to specific machines and keep them for later deployments.
+  uc caddy deploy --machine machine1,machine2
+
+  # Go back to deploying to all machines.
+  uc caddy deploy --machine ""`,
 		RunE: func(cmd *cobra.Command, args []string) error {
 			uncli := cmd.Context().Value("cli").(*cli.CLI)
+
+			opts.caddyfileChanged = cmd.Flag("caddyfile").Changed
+			opts.imageChanged = cmd.Flag("image").Changed
+			opts.machinesChanged = cmd.Flag("machine").Changed
+
 			return runDeploy(cmd.Context(), uncli, opts)
 		},
 	}
 
 	cmd.Flags().StringVar(&opts.caddyfile, "caddyfile", "",
-		"Path to a custom global Caddy config (Caddyfile) that will be prepended to the auto-generated Caddy config.")
+		"Path to a custom global Caddy config (Caddyfile) that will be prepended to the auto-generated Caddy config.\n"+
+			"An empty value resets it to the default config that enables cluster storage.\n"+
+			"(default is the current custom config or the default config)")
 	cmd.Flags().StringVar(&opts.image, "image", "",
-		"Caddy Docker image to deploy. (default caddy:LATEST_VERSION)")
+		"Caddy Docker image to deploy. It must include the Uncloud storage module if the Caddy config uses it.\n"+
+			"An empty value resets it to the latest version of the Uncloud Caddy image.\n"+
+			"(default is the current custom image or "+client.CaddyImage+":LATEST_VERSION)")
 	cmd.Flags().StringSliceVarP(&opts.machines, "machine", "m", nil,
-		"Machine names or IDs to deploy to. Can be specified multiple times or as a comma-separated "+
-			"list. (default is all machines)")
+		"Machine names or IDs to deploy to. Can be specified multiple times or as a comma-separated list.\n"+
+			"An empty value resets it to all machines.\n"+
+			"(default is the current machines or all machines)")
 
 	completion.MachinesFlag(cmd)
 
@@ -55,13 +101,13 @@ func NewDeployCommand() *cobra.Command {
 }
 
 func runDeploy(ctx context.Context, uncli *cli.CLI, opts deployOptions) error {
-	caddyfile := ""
+	config := ""
 	if opts.caddyfile != "" {
 		data, err := os.ReadFile(opts.caddyfile)
 		if err != nil {
 			return fmt.Errorf("read Caddyfile: %w", err)
 		}
-		caddyfile = strings.TrimSpace(string(data))
+		config = strings.TrimSpace(string(data))
 	}
 
 	clusterClient, err := uncli.ConnectCluster(ctx)
@@ -70,6 +116,10 @@ func runDeploy(ctx context.Context, uncli *cli.CLI, opts deployOptions) error {
 	}
 	defer clusterClient.Close()
 
+	if err = clusterClient.Caddy.CheckDaemonVersions(ctx); err != nil {
+		return err
+	}
+
 	svc, err := clusterClient.InspectService(ctx, client.CaddyServiceName)
 	if err != nil {
 		if !errors.Is(err, api.ErrNotFound) {
@@ -100,26 +150,48 @@ func runDeploy(ctx context.Context, uncli *cli.CLI, opts deployOptions) error {
 		}
 	}
 
-	if opts.image != "" {
-		fmt.Println(tui.Faint.Render("target image: ") + tui.FormatImage(opts.image, tui.Green))
+	current := svc.Spec()
+	deployOpts := resolveDeploymentOptions(current, opts, config)
+	configChanged := deployOpts.ConfigOrDefault() != current.CaddyConfig()
+
+	if svc.ID != "" && configChanged {
+		printCaddyConfig("current global Caddy config:", current.CaddyConfig())
 	}
 
 	fmt.Println()
 	fmt.Println("Preparing a deployment plan...")
 
-	placement := api.Placement{
-		Machines: cli.ExpandCommaSeparatedValues(opts.machines),
-	}
-	d, err := clusterClient.Caddy.NewDeployment(ctx, client.CaddyDeploymentOptions{
-		Image: opts.image, Config: caddyfile, Placement: placement,
-	})
+	d, err := clusterClient.Caddy.NewDeployment(ctx, deployOpts)
 	if err != nil {
 		return fmt.Errorf("create caddy deployment: %w", err)
 	}
+	target := d.Spec
 
-	if opts.image == "" {
-		fmt.Println(tui.Faint.Render("target image: ") + tui.FormatImage(d.Spec.Container.Image,
-			tui.Green) + tui.Faint.Render(" (latest stable)"))
+	// The Uncloud Caddy image resolves to the latest version allowed by this CLI, which is older than the running image
+	// if a newer CLI deployed it. Continuing would downgrade the image and replace its default config.
+	if deployOpts.Image == "" && client.IsNewerCaddyImage(current.Container.Image, target.Container.Image) {
+		return fmt.Errorf("caddy service runs image '%s' which is newer than the latest version '%s' supported by "+
+			"this uc version: upgrade uc or specify the image with --image",
+			current.Container.Image, target.Container.Image)
+	}
+
+	imageNote := " (latest)"
+	if deployOpts.Image != "" {
+		imageNote = " (custom)"
+		if !opts.imageChanged {
+			imageNote = " (custom, use --image \"\" for the latest version)"
+		}
+	}
+	fmt.Println(tui.Faint.Render("target image: ") + tui.FormatImage(target.Container.Image, tui.Green) +
+		tui.Faint.Render(imageNote))
+
+	if configChanged {
+		if deployOpts.Config != nil {
+			// The user provided this config so there is no need to print its content.
+			fmt.Println(tui.Faint.Render("target global Caddy config: ") + opts.caddyfile)
+		} else {
+			printCaddyConfig("target global Caddy config: (default)", deployOpts.ConfigOrDefault())
+		}
 	}
 
 	plan, err := d.Plan(ctx)
@@ -131,7 +203,7 @@ func runDeploy(ctx context.Context, uncli *cli.CLI, opts deployOptions) error {
 		fmt.Printf("%s service is up to date.\n", client.CaddyServiceName)
 	} else {
 		if svc.ID == "" {
-			if len(opts.machines) > 0 {
+			if len(deployOpts.Placement.Machines) > 0 {
 				fmt.Println("This will run a Caddy container on each selected machine.")
 			} else {
 				fmt.Println("This will run a Caddy container on each machine.")
@@ -163,6 +235,14 @@ func runDeploy(ctx context.Context, uncli *cli.CLI, opts deployOptions) error {
 		fmt.Println(summary)
 		fmt.Println()
 
+		warnings := deploymentWarnings(current, target, opts)
+		for _, warning := range warnings {
+			tui.PrintWarning(warning)
+		}
+		if len(warnings) > 0 {
+			fmt.Println()
+		}
+
 		title := "Proceed with deployment?"
 		// Include the direct connection or context name in the confirmation prompt to avoid accidentally
 		// deploying to the wrong cluster.
@@ -195,6 +275,98 @@ func runDeploy(ctx context.Context, uncli *cli.CLI, opts deployOptions) error {
 	return UpdateDomainRecords(ctx, clusterClient, uncli.ProgressOut())
 }
 
+// resolveDeploymentOptions returns the deployment options for the flags and the current service spec, which is zero if
+// the service doesn't exist. Each flag works on its own: a specified flag overrides the value and an empty one resets
+// it to the default. A flag that isn't specified keeps the explicitly set value.
+func resolveDeploymentOptions(
+	current api.ServiceSpec, opts deployOptions, config string,
+) client.CaddyDeploymentOptions {
+	var resolved client.CaddyDeploymentOptions
+
+	if opts.imageChanged {
+		resolved.Image = opts.image
+	} else if _, custom := current.Labels[api.LabelCaddyImageCustom]; custom {
+		resolved.Image = current.Container.Image
+	}
+
+	if opts.caddyfileChanged {
+		if opts.caddyfile != "" {
+			resolved.Config = new(config)
+		}
+	} else if _, custom := current.Labels[api.LabelCaddyConfigCustom]; custom {
+		resolved.Config = new(current.CaddyConfig())
+	}
+
+	if opts.machinesChanged {
+		resolved.Placement.Machines = cli.ExpandCommaSeparatedValues(opts.machines)
+	} else if _, managed := current.Labels[api.LabelCaddyManaged]; managed {
+		resolved.Placement = current.Placement
+	}
+
+	return resolved
+}
+
+// deploymentWarnings returns the consequences of deploying the target spec over the current one, which is zero if
+// the service doesn't exist.
+func deploymentWarnings(current, target api.ServiceSpec, opts deployOptions) []string {
+	var warnings []string
+	exists := current.Name != ""
+
+	if _, managed := current.Labels[api.LabelCaddyManaged]; exists && !managed {
+		warnings = append(warnings, "'uc caddy deploy' doesn't manage this caddy service yet, so this deployment "+
+			"replaces its configuration, including any custom global Caddy config.\n"+
+			"If you manage it with a Compose file, cancel and deploy with 'uc deploy' instead.")
+	}
+
+	currentStorage := client.CaddyStorageModule(current.CaddyConfig())
+	targetStorage := client.CaddyStorageModule(target.CaddyConfig())
+	if exists && currentStorage != targetStorage {
+		warning := fmt.Sprintf("Caddy certificate storage changes from %s to %s.\n"+
+			"Caddy doesn't automatically migrate certificates, so all of them will be reissued and HTTPS may fail "+
+			"for those domains until that finishes.\n"+
+			"To migrate them first, see %s/concepts/ingress/cluster-storage-for-caddy",
+			caddyStorageName(currentStorage), caddyStorageName(targetStorage), version.DocsURL)
+		if !opts.caddyfileChanged {
+			warning += "\nTo keep the current storage, specify a custom Caddyfile that uses it with --caddyfile."
+		}
+		warnings = append(warnings, warning)
+	}
+
+	imageOrConfigChanged := current.Container.Image != target.Container.Image ||
+		current.CaddyConfig() != target.CaddyConfig()
+	if targetStorage == client.CaddyStorageUncloud && imageOrConfigChanged &&
+		!client.IsDefaultCaddyImage(target.Container.Image) {
+		warnings = append(warnings, fmt.Sprintf("Image '%s' must include the Uncloud storage module to use "+
+			"'storage uncloud'. Otherwise, Caddy won't start or apply the new config.\n"+
+			"Check 'uc caddy config' after the deployment for errors.", target.Container.Image))
+	}
+
+	return warnings
+}
+
+// caddyStorageName returns a user-friendly name of the Caddy storage module.
+func caddyStorageName(module string) string {
+	switch module {
+	case client.CaddyStorageFileSystem:
+		return "local"
+	case client.CaddyStorageUncloud:
+		return "cluster"
+	default:
+		return "'" + module + "'"
+	}
+}
+
+// printCaddyConfig prints the title and the indented config or "none" if it's empty.
+func printCaddyConfig(title, config string) {
+	if config == "" {
+		lipgloss.Println(tui.Faint.Render(title) + " none")
+		return
+	}
+
+	lipgloss.Println(tui.Faint.Render(title))
+	fmt.Println(config)
+}
+
 func UpdateDomainRecords(ctx context.Context, clusterClient *client.Client, progressOut *streams.Out) error {
 	domain, err := clusterClient.GetDomain(ctx)
 	if err != nil {