feat(surf): print the serve URL and admin status on startup

- Add surf.Router.AdminPrefix (additive): the admin mount path and true
  when BuildRouter mounted the cabana admin, false otherwise
- serve binds with net.Listen before printing, so a busy port fails
  without a misleading URL, then prints the listen address with a
  browser URL and an admin status line: the admin URL, a warning naming
  summer admin:create when backend_users is empty or missing, or
  admin: off with the steps to add an admin controller
- The administrator count is bounded by a 2 s timeout and never fails boot
- route:list ends with the same admin status line
- surf and cabana READMEs and the console and routing docs describe the output

modules/cabana/README.md

@@ -178,7 +178,7 @@ func (p *Plugin) AdminControllers() []pact.AdminController {
 func (p *Plugin) AdminFS() fs.FS { return adminFS }
 ```
 
-`config_list.yaml` and `config_form.yaml` reference the model files with WinterCMS paths such as `~/plugins/acme/blog/models/post/columns.yaml`. At boot, `surf.BuildRouter` calls `cabana.Activate` with the activated plugins and mounts the returned `cabana.Routes`; when no plugin registers an admin controller, `cabana.Activate` returns nil and no admin routes exist. Record and user lookups use the `*gorm.DB` that [lagoon](../lagoon/README.md) publishes on the `backpack.App`.
+`config_list.yaml` and `config_form.yaml` reference the model files with WinterCMS paths such as `~/plugins/acme/blog/models/post/columns.yaml`. At boot, `surf.BuildRouter` calls `cabana.Activate` with the activated plugins and mounts the returned `cabana.Routes`; when no plugin registers an admin controller, `cabana.Activate` returns nil and no admin routes exist. `surf.Router.AdminPrefix` reports which case applies, and the `serve` and `route:list` commands print it as an admin status line. Record and user lookups use the `*gorm.DB` that [lagoon](../lagoon/README.md) publishes on the `backpack.App`.
 
 ## API reference
 

modules/surf/README.md

@@ -22,7 +22,7 @@ surf turns the routes that plugins declare through `pact.HasRoutes` into one `ht
 - Path-scoped CORS configured with the same keys as Laravel's `config/cors.php` (`surf.CORSConfig`), including preflight handling. Every `OPTIONS` request on a CORS path is answered with 204 before routing, with the headers Laravel's `HandleCors` sends: `Cache-Control: no-cache, private` always and, on a preflight (an `Origin` and an `Access-Control-Request-Method`), the requested method (upper-cased) and headers echoed in `Access-Control-Allow-Methods` and `Access-Control-Allow-Headers` when `*` allows any, `Vary` on the request headers and PHP's default `Content-Type: text/html; charset=UTF-8`.
 - Optional `surf.LocaleResolver`: a compiled plugin publishes the interface through backpack; surf looks it up without importing the plugin. When present, it may strip an enabled locale prefix before routing and writes a validated code with `towel.WithLocale`. When absent, hosts keep the raw `Accept-Language` header and `surf.LocaleFromPrincipal` overlay.
 - `surf.LocaleFromPrincipal` switches the request locale to the signed-in user's preferred locale.
-- A read-only route table (`surf.Router.Routes`) and the `serve` and `route:list` commands.
+- A read-only route table (`surf.Router.Routes`), the admin mount status (`surf.Router.AdminPrefix`) and the `serve` and `route:list` commands.
 
 ## Usage
 
@@ -108,6 +108,7 @@ The generated application `main` wires surf in with `surf.ServeCommand` and `sur
 | `surf.Router.RegisterMiddleware` | Stores a named middleware; duplicates fail. |
 | `surf.Router.RegisterMiddlewareFactory` | Stores a parameterized middleware used as `name:param`. |
 | `surf.Router.Routes` | Returns a copy of the registered routes as `surf.RouteInfo` values. |
+| `surf.Router.AdminPrefix` | The admin mount path and true when `surf.BuildRouter` mounted the cabana admin; false when no plugin registers an admin controller. |
 | `surf.RouteInfo` | Method, pattern, owning plugin, middleware and raw flag of one route. |
 | `surf.Use` | Builds a middleware name list for a group. |
 | `surf.Constraint` | A compiled path-parameter restriction built by `surf.Regex` or `surf.Enum`. |
@@ -162,8 +163,8 @@ The `serve` command also opens the database through [lagoon](../lagoon/README.md
 
 | Command | Flags | Description |
 |---------|-------|-------------|
-| `serve` | `--addr` (default `:8080`) | Opens the database and uploads bucket, assembles the router, starts the in-process job worker (see `queue.work_in_serve`) and serves HTTP until SIGINT or SIGTERM, then shuts the server and the worker down gracefully within 10 seconds. |
-| `route:list` | none | Builds the router the same way `serve` does, without opening the database or listening, and prints a table of method, pattern, plugin, middleware and raw flag for every route. |
+| `serve` | `--addr` (default `:8080`) | Opens the database and uploads bucket, assembles the router, binds the address, starts the in-process job worker (see `queue.work_in_serve`) and serves HTTP until SIGINT or SIGTERM, then shuts the server and the worker down gracefully within 10 seconds. After binding it prints the listen address with a browser URL (an unspecified host shows as 127.0.0.1) and an admin status line: the admin URL, with a warning naming `summer admin:create` when no administrator exists yet, or `admin: off` with the steps to add an admin controller. |
+| `route:list` | none | Builds the router the same way `serve` does, without opening the database or listening, and prints a table of method, pattern, plugin, middleware and raw flag for every route, followed by the admin status line (`admin: mounted at <prefix>` or `admin: off`). |
 
 ## Dependencies
 

modules/surf/admin_prefix_test.go

@@ -1,6 +1,7 @@
 package surf
 
 import (
+	"bytes"
 	"io/fs"
 	"net/http"
 	"os"
@@ -10,6 +11,7 @@ import (
 	"testing/fstest"
 
 	"git.golem15.com/golem15/summercms/modules/backpack"
+	"git.golem15.com/golem15/summercms/modules/bonfire"
 	"git.golem15.com/golem15/summercms/modules/compass"
 	"git.golem15.com/golem15/summercms/modules/pact"
 	"git.golem15.com/golem15/summercms/modules/party"
@@ -177,3 +179,57 @@ func (p prefixRoutePlugin) Routes(r pact.Router) error {
 	})
 	return nil
 }
+
+// TestRouterAdminPrefix reports the admin mount path BuildRouter used.
+func TestRouterAdminPrefix(t *testing.T) {
+	for _, tc := range []struct {
+		name    string
+		app     *backpack.App
+		plugins []party.Plugin
+		prefix  string
+		mounted bool
+	}{
+		{"configured prefix", adminPrefixApp(t), []party.Plugin{adminPrefixPlugin{}}, "/acme-admin", true},
+		{"default prefix", adminPrefixAppWith(t, ""), []party.Plugin{adminPrefixPlugin{}}, "/backend", true},
+		{"no admin controllers", adminPrefixApp(t), []party.Plugin{prefixRoutePlugin{id: "acme.site", method: http.MethodGet, path: "/hello"}}, "", false},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			r, err := BuildRouter(tc.app, tc.plugins)
+			if err != nil {
+				t.Fatal(err)
+			}
+			prefix, mounted := r.AdminPrefix()
+			if prefix != tc.prefix || mounted != tc.mounted {
+				t.Fatalf("AdminPrefix() = (%q, %v), want (%q, %v)", prefix, mounted, tc.prefix, tc.mounted)
+			}
+		})
+	}
+	if prefix, mounted := (*Router)(nil).AdminPrefix(); prefix != "" || mounted {
+		t.Fatalf("nil router AdminPrefix() = (%q, %v)", prefix, mounted)
+	}
+}
+
+// TestRouteListAdminStatus ends the route table with the admin status line.
+func TestRouteListAdminStatus(t *testing.T) {
+	for _, tc := range []struct {
+		name    string
+		app     *backpack.App
+		plugins []party.Plugin
+		want    string
+	}{
+		{"mounted", adminPrefixApp(t), []party.Plugin{adminPrefixPlugin{}}, "admin: mounted at /acme-admin"},
+		{"off", adminPrefixApp(t), []party.Plugin{prefixRoutePlugin{id: "acme.site", method: http.MethodGet, path: "/hello"}}, "admin: off — no plugin registers an admin controller"},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			var buf bytes.Buffer
+			out := bonfire.NewOutput(strings.NewReader(""), &buf, &buf)
+			if err := RouteListCommand(tc.app, tc.plugins).Run(t.Context(), nil, out); err != nil {
+				t.Fatal(err)
+			}
+			got := strings.TrimRight(buf.String(), "\n")
+			if !strings.HasSuffix(got, tc.want) {
+				t.Fatalf("route:list output does not end with %q:\n%s", tc.want, got)
+			}
+		})
+	}
+}

modules/surf/routelist_command.go

@@ -11,7 +11,8 @@ import (
 )
 
 // RouteListCommand builds the router the same way ServeCommand does, then
-// renders Routes() as a table instead of serving.
+// renders Routes() as a table instead of serving, followed by the admin
+// status line.
 func RouteListCommand(app *backpack.App, plugins []party.Plugin) bonfire.Command {
 	return bonfire.Command{
 		Name:        "route:list",
@@ -33,6 +34,11 @@ func RouteListCommand(app *backpack.App, plugins []party.Plugin) bonfire.Command
 				})
 			}
 			out.Table([]string{"Method", "Pattern", "Plugin", "Middleware", "Raw"}, rows)
+			if prefix, mounted := r.AdminPrefix(); mounted {
+				out.Info("admin: mounted at " + prefix)
+			} else {
+				out.Info(adminOffText)
+			}
 			return nil
 		},
 	}

modules/surf/router.go

@@ -60,6 +60,8 @@ type Router struct {
 	uploadBytes  int64
 	built        map[string]pact.Middleware
 	app          *backpack.App
+	adminPrefix  string
+	adminMounted bool
 }
 
 var (
@@ -556,6 +558,8 @@ func BuildRouter(app *backpack.App, plugins []party.Plugin) (*Router, error) {
 		if err := r.checkAdminPrefix(admin.Prefix); err != nil {
 			return nil, err
 		}
+		r.adminPrefix = admin.Prefix
+		r.adminMounted = true
 	}
 	for _, rt := range r.routes {
 		if _, err := r.wrap(rt); err != nil {

modules/surf/routetable.go

@@ -10,6 +10,15 @@ type RouteInfo struct {
 	Raw        bool
 }
 
+// AdminPrefix reports the cabana admin mount path set by BuildRouter. False
+// means no plugin registers an admin controller, so no admin routes exist.
+func (r *Router) AdminPrefix() (string, bool) {
+	if r == nil || !r.adminMounted {
+		return "", false
+	}
+	return r.adminPrefix, true
+}
+
 // Routes returns a defensive copy of every registered route.
 func (r *Router) Routes() []RouteInfo {
 	if r == nil {

modules/surf/serve.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"net"
 	"net/http"
+	"net/netip"
 	"os"
 	"os/signal"
 	"strings"
@@ -13,11 +14,13 @@ import (
 
 	"git.golem15.com/golem15/summercms/modules/backpack"
 	"git.golem15.com/golem15/summercms/modules/bonfire"
+	"git.golem15.com/golem15/summercms/modules/cabana"
 	"git.golem15.com/golem15/summercms/modules/conga"
 	"git.golem15.com/golem15/summercms/modules/lagoon"
 	"git.golem15.com/golem15/summercms/modules/lagoon/attach"
 	"git.golem15.com/golem15/summercms/modules/party"
 	"gocloud.dev/blob"
+	"gorm.io/gorm"
 )
 
 // ServeCommand starts a signal-aware HTTP server on the assembled router.
@@ -50,22 +53,36 @@ func ServeCommand(app *backpack.App, plugins []party.Plugin) bonfire.Command {
 				return err
 			}
 			defer bucket.Close()
-			h, err := Assemble(app, plugins)
+			r, err := BuildRouter(app, plugins)
+			if err != nil {
+				return err
+			}
+			h, err := r.compile()
+			if err != nil {
+				return err
+			}
+			ln, err := net.Listen("tcp", addr)
 			if err != nil {
 				return err
 			}
 			worker, err := conga.StartServeWorker(ctx, app, plugins)
 			if err != nil {
+				_ = ln.Close()
 				return err
 			}
 			if worker != nil {
 				out.Info(fmt.Sprintf("job worker started on queues: %s", strings.Join(worker.Queues(), ", ")))
 			}
+			prefix, mounted := r.AdminPrefix()
+			admins := adminsUnknown
+			if mounted {
+				admins = countAdmins(ctx, gdb)
+			}
+			printBanner(out, serveBanner(addr, prefix, mounted, admins))
 			srv := &http.Server{Addr: addr, Handler: h, BaseContext: func(net.Listener) context.Context { return ctx }}
 			errCh := make(chan error, 1)
 			go func() {
-				out.Info(fmt.Sprintf("listening on %s", addr))
-				errCh <- srv.ListenAndServe()
+				errCh <- srv.Serve(ln)
 			}()
 			shutdownCtx := func() (context.Context, context.CancelFunc) {
 				return context.WithTimeout(context.Background(), 10*time.Second)
@@ -121,3 +138,119 @@ func publishUploads(ctx context.Context, app *backpack.App) (*blob.Bucket, error
 	}
 	return bucket, nil
 }
+
+// adminCreateCommand is the command the startup hints name for creating the
+// first backend administrator.
+const adminCreateCommand = "summer admin:create --email you@example.com --superuser"
+
+// adminOffText is the admin status line serve and route:list print when no
+// plugin registers an admin controller.
+const adminOffText = "admin: off — no plugin registers an admin controller"
+
+// serveURL turns a listen address into a URL a browser can open. An empty or
+// unspecified host (0.0.0.0, ::) becomes 127.0.0.1, port 80 is left out and
+// an IPv6 host is bracketed. An address that does not parse gives "".
+func serveURL(addr string) string {
+	host, port, err := net.SplitHostPort(addr)
+	if err != nil || port == "" {
+		return ""
+	}
+	if host == "" {
+		host = "127.0.0.1"
+	} else if ip, err := netip.ParseAddr(host); err == nil && ip.IsUnspecified() {
+		host = "127.0.0.1"
+	}
+	hostport := net.JoinHostPort(host, port)
+	if port == "80" {
+		hostport = host
+		if strings.Contains(host, ":") {
+			hostport = "[" + host + "]"
+		}
+	}
+	return "http://" + hostport + "/"
+}
+
+// adminPresence is what serve could learn about backend administrators.
+type adminPresence int
+
+const (
+	adminsUnknown adminPresence = iota
+	adminsMissingTable
+	adminsNone
+	adminsPresent
+)
+
+// countAdmins checks whether backend_users exists and holds a row. It is
+// bounded by a 2 second timeout and maps every failure to adminsUnknown, so
+// it never fails or blocks boot. HasTable queries information_schema, so a
+// missing table does not reach the GORM error log.
+func countAdmins(ctx context.Context, gdb *gorm.DB) adminPresence {
+	if gdb == nil {
+		return adminsUnknown
+	}
+	c, cancel := context.WithTimeout(ctx, 2*time.Second)
+	defer cancel()
+	db := gdb.WithContext(c)
+	if !db.Migrator().HasTable(&cabana.BackendUser{}) {
+		if c.Err() != nil {
+			return adminsUnknown
+		}
+		return adminsMissingTable
+	}
+	var n int64
+	if err := db.Model(&cabana.BackendUser{}).Count(&n).Error; err != nil {
+		return adminsUnknown
+	}
+	if n == 0 {
+		return adminsNone
+	}
+	return adminsPresent
+}
+
+// bannerLine is one startup line; warn lines print with the warning symbol.
+type bannerLine struct {
+	warn bool
+	text string
+}
+
+// serveBanner builds the lines serve prints once the port is bound: the
+// listen address with a browser URL, then the admin status.
+func serveBanner(addr, adminPrefix string, mounted bool, admins adminPresence) []bannerLine {
+	url := serveURL(addr)
+	listen := "listening on " + addr
+	if url != "" {
+		listen += ", open " + url
+	}
+	lines := []bannerLine{{text: listen}}
+	if !mounted {
+		return append(lines,
+			bannerLine{text: adminOffText},
+			bannerLine{text: "to add one, run summer make:admin-controller <vendor.plugin> <Name>, then summer build, summer migrate and " + adminCreateCommand + "; the admin needs SUMMER_ADMIN__JWT__SECRET, which summer new writes to .env"},
+		)
+	}
+	if url != "" {
+		lines = append(lines, bannerLine{text: "admin: " + strings.TrimSuffix(url, "/") + adminPrefix})
+	} else {
+		lines = append(lines, bannerLine{text: "admin: mounted at " + adminPrefix})
+	}
+	switch admins {
+	case adminsNone:
+		lines = append(lines, bannerLine{warn: true, text: "no administrators yet; create one with " + adminCreateCommand})
+	case adminsMissingTable:
+		lines = append(lines, bannerLine{warn: true, text: "the admin tables do not exist yet; run summer migrate, then " + adminCreateCommand})
+	case adminsUnknown:
+		lines = append(lines, bannerLine{text: "sign in with an administrator; " + adminCreateCommand + " creates one"})
+	}
+	return lines
+}
+
+// printBanner writes banner lines as info or warning output.
+func printBanner(out bonfire.Output, lines []bannerLine) {
+	for _, l := range lines {
+		if l.warn {
+			out.Warning(l.text)
+			continue
+		}
+		out.Info(l.text)
+	}
+}

modules/surf/serve_test.go

@@ -1,12 +1,15 @@
 package surf
 
 import (
+	"bytes"
 	"os"
 	"path/filepath"
+	"slices"
 	"strings"
 	"testing"
 
 	"git.golem15.com/golem15/summercms/modules/backpack"
+	"git.golem15.com/golem15/summercms/modules/bonfire"
 	"git.golem15.com/golem15/summercms/modules/compass"
 	"gocloud.dev/blob"
 )
@@ -51,3 +54,71 @@ func serveTestApp(t *testing.T, storageYAML string) *backpack.App {
 	}
 	return backpack.New(cfg)
 }
+
+func TestServeURL(t *testing.T) {
+	for _, tc := range []struct{ addr, want string }{
+		{":8123", "http://127.0.0.1:8123/"},
+		{"127.0.0.1:9000", "http://127.0.0.1:9000/"},
+		{"[::1]:8080", "http://[::1]:8080/"},
+		{"0.0.0.0:80", "http://127.0.0.1/"},
+		{"[::]:8080", "http://127.0.0.1:8080/"},
+		{"localhost:3000", "http://localhost:3000/"},
+		{"8080", ""},
+		{"", ""},
+		{"127.0.0.1:", ""},
+	} {
+		if got := serveURL(tc.addr); got != tc.want {
+			t.Errorf("serveURL(%q) = %q, want %q", tc.addr, got, tc.want)
+		}
+	}
+}
+
+func TestServeBanner(t *testing.T) {
+	listen := bannerLine{text: "listening on :8123, open http://127.0.0.1:8123/"}
+	mounted := bannerLine{text: "admin: http://127.0.0.1:8123/backend"}
+	create := "summer admin:create --email you@example.com --superuser"
+	for _, tc := range []struct {
+		name    string
+		addr    string
+		prefix  string
+		mounted bool
+		admins  adminPresence
+		want    []bannerLine
+	}{
+		{"present", ":8123", "/backend", true, adminsPresent, []bannerLine{listen, mounted}},
+		{"none", ":8123", "/backend", true, adminsNone, []bannerLine{listen, mounted,
+			{warn: true, text: "no administrators yet; create one with " + create}}},
+		{"missing table", ":8123", "/backend", true, adminsMissingTable, []bannerLine{listen, mounted,
+			{warn: true, text: "the admin tables do not exist yet; run summer migrate, then " + create}}},
+		{"unknown", ":8123", "/backend", true, adminsUnknown, []bannerLine{listen, mounted,
+			{text: "sign in with an administrator; " + create + " creates one"}}},
+		{"off", ":8123", "", false, adminsUnknown, []bannerLine{listen,
+			{text: "admin: off — no plugin registers an admin controller"},
+			{text: "to add one, run summer make:admin-controller <vendor.plugin> <Name>, then summer build, summer migrate and " + create + "; the admin needs SUMMER_ADMIN__JWT__SECRET, which summer new writes to .env"}}},
+		{"unparsable address", "8080", "/backend", true, adminsPresent, []bannerLine{
+			{text: "listening on 8080"}, {text: "admin: mounted at /backend"}}},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			got := serveBanner(tc.addr, tc.prefix, tc.mounted, tc.admins)
+			if !slices.Equal(got, tc.want) {
+				t.Fatalf("serveBanner:\n got %#v\nwant %#v", got, tc.want)
+			}
+		})
+	}
+}
+
+func TestPrintBanner(t *testing.T) {
+	var buf bytes.Buffer
+	out := bonfire.NewOutput(strings.NewReader(""), &buf, &buf)
+	printBanner(out, []bannerLine{{text: "plain"}, {warn: true, text: "careful"}})
+	got := buf.String()
+	if !strings.Contains(got, "ℹ plain") || !strings.Contains(got, "⚠ careful") {
+		t.Fatalf("printBanner output = %q", got)
+	}
+}
+
+func TestCountAdminsNilDB(t *testing.T) {
+	if got := countAdmins(t.Context(), nil); got != adminsUnknown {
+		t.Fatalf("countAdmins(nil) = %v, want adminsUnknown", got)
+	}
+}