Allow dots in app names (closes #260)

App names may now contain dots, such as sneak.berlin: runs of
lowercase letters and numbers joined by single dots or by hyphens,
2 to 63 characters. This is Docker's rule for an image name, and the
app's image is upaas-<name>; it also keeps a dot off either end, so
the name is safe as a directory and log file name.

The new and edit app forms use the same pattern. Their old one was not
a valid regular expression under the flag browsers compile it with, so
browsers ignored it.

A test deploys an app named sneak.berlin against the fake Docker API
and checks the image and container names with Docker's own rules.

Model: opus-5-5

CONVENTIONS.md

@@ -115,13 +115,15 @@ import (
 )
 
 var (
-    Appname string = "CHANGEME"
-    Version string
+    Appname   string = "CHANGEME"
+    Version   string
+    Buildarch string
 )
 
 func main() {
     globals.Appname = Appname
     globals.Version = Version
+    globals.Buildarch = Buildarch
 
     fx.New(
         fx.Provide(
@@ -821,7 +823,7 @@ func (l *Logger) Identify() {
     l.log.Info("starting",
         "appname", l.params.Globals.Appname,
         "version", l.params.Globals.Version,
-        "arch", runtime.GOARCH,
+        "buildarch", l.params.Globals.Buildarch,
     )
 }
 ```
@@ -941,20 +943,23 @@ import "go.uber.org/fx"
 
 // Package-level variables (set from main)
 var (
-    Appname string
-    Version string
+    Appname   string
+    Version   string
+    Buildarch string
 )
 
 // Struct for DI
 type Globals struct {
-    Appname string
-    Version string
+    Appname   string
+    Version   string
+    Buildarch string
 }
 
 func New(lc fx.Lifecycle) (*Globals, error) {
     n := &Globals{
-        Appname: Appname,
-        Version: Version,
+        Appname:   Appname,
+        Buildarch: Buildarch,
+        Version:   Version,
     }
     return n, nil
 }
@@ -965,13 +970,15 @@ func New(lc fx.Lifecycle) (*Globals, error) {
 ```go
 // cmd/httpd/main.go
 var (
-    Appname string = "CHANGEME"  // Default, overridden by build
-    Version string               // Set at build time
+    Appname   string = "CHANGEME"  // Default, overridden by build
+    Version   string               // Set at build time
+    Buildarch string               // Set at build time
 )
 
 func main() {
     globals.Appname = Appname
     globals.Version = Version
+    globals.Buildarch = Buildarch
     // ...
 }
 ```
@@ -982,9 +989,10 @@ Use ldflags to inject version information at build time:
 
 ```makefile
 VERSION := $(shell git describe --tags --always)
+BUILDARCH := $(shell go env GOARCH)
 
 build:
-    go build -ldflags "-X main.Version=$(VERSION)" ./cmd/httpd
+    go build -ldflags "-X main.Version=$(VERSION) -X main.Buildarch=$(BUILDARCH)" ./cmd/httpd
 ```
 
 ---

Makefile

@@ -2,7 +2,8 @@
 
 BINARY := upaasd
 VERSION := $(shell git describe --tags --always --dirty 2>/dev/null || echo "dev")
-LDFLAGS := -X main.Version=$(VERSION)
+BUILDARCH := $(shell go env GOARCH)
+LDFLAGS := -X main.Version=$(VERSION) -X main.Buildarch=$(BUILDARCH)
 
 all: check build
 

TODO.md

@@ -21,16 +21,10 @@ regress.
 # Completed Steps
 
 - 2026-10-02: App names may contain dots, such as `sneak.berlin`: lowercase
-  letters and numbers joined by single dots or by hyphens, 2 to 63 characters.
-  Docker accepts every such name in the image name `upaas-<name>`; a dot needs a
-  letter or number on both sides because Docker requires it. The new and edit
-  app forms check the same rule; browsers ignored their old pattern, which was
-  not a valid regular expression there (#260).
-
-- 2026-10-02: The build no longer passes the CPU architecture in: upaas reads it
-  from Go's `runtime.GOARCH` when it runs, and the startup log line reports it
-  as `arch`. `CONVENTIONS.md` follows the updated conventions in `sneak/prompts`
-  (#259).
+  letters and numbers joined by single dots or by hyphens, 2 to 63 characters,
+  which is Docker's rule for the image name `upaas-<name>`. The new and edit app
+  forms check the same rule; browsers ignored their old pattern, which was not a
+  valid regular expression there (#260).
 
 - 2026-10-01: Built images are tagged `upaas-<app>:<short hash>`, git's short
   form of the commit built, instead of the deployment number. A redeploy of a

cmd/upaasd/main.go

@@ -25,13 +25,15 @@ import (
 // Build-time variables injected by linker flags (-ldflags).
 // These must be exported package-level variables for the build system.
 var (
-	Appname = "upaas" //nolint:gochecknoglobals // build-time variable
-	Version string    //nolint:gochecknoglobals // build-time variable
+	Appname   = "upaas" //nolint:gochecknoglobals // build-time variable
+	Version   string    //nolint:gochecknoglobals // build-time variable
+	Buildarch string    //nolint:gochecknoglobals // build-time variable
 )
 
 func main() {
 	globals.SetAppname(Appname)
 	globals.SetVersion(Version)
+	globals.SetBuildarch(Buildarch)
 
 	fx.New(
 		fx.Provide(

internal/globals/globals.go

@@ -12,15 +12,17 @@ import (
 //
 //nolint:gochecknoglobals // Required for ldflags injection at build time
 var (
-	mu      sync.RWMutex
-	appname string
-	version string
+	mu        sync.RWMutex
+	appname   string
+	version   string
+	buildarch string
 )
 
 // Globals holds build-time variables for dependency injection.
 type Globals struct {
-	Appname string
-	Version string
+	Appname   string
+	Version   string
+	Buildarch string
 }
 
 // New creates a new Globals instance from package-level variables.
@@ -29,8 +31,9 @@ func New(_ fx.Lifecycle) (*Globals, error) {
 	defer mu.RUnlock()
 
 	return &Globals{
-		Appname: appname,
-		Version: version,
+		Appname:   appname,
+		Version:   version,
+		Buildarch: buildarch,
 	}, nil
 }
 
@@ -49,3 +52,11 @@ func SetVersion(ver string) {
 
 	version = ver
 }
+
+// SetBuildarch sets the build architecture (used for testing and main init).
+func SetBuildarch(arch string) {
+	mu.Lock()
+	defer mu.Unlock()
+
+	buildarch = arch
+}

internal/handlers/app_name_validation.go

@@ -14,9 +14,8 @@ const (
 )
 
 // validAppNameRe matches runs of lowercase letters and digits joined by
-// single dots or by hyphens, such as "my-app" or "sneak.berlin". Docker
-// accepts every name it allows as the app's image name, upaas-<name>; a
-// dot needs a letter or digit on both sides because Docker requires it.
+// single dots or by hyphens, such as "my-app" or "sneak.berlin". This is
+// Docker's rule for an image name, and the app's image is upaas-<name>.
 // It also keeps the name from being "." or ".." or starting or ending
 // with a dot, so it is safe as a directory and file name. The pattern
 // attribute of the name field on the new and edit app forms is the same.

internal/logger/logger.go

@@ -4,7 +4,6 @@ package logger
 import (
 	"log/slog"
 	"os"
-	"runtime"
 
 	"go.uber.org/fx"
 
@@ -82,6 +81,6 @@ func (l *Logger) Identify() {
 	l.log.Info("starting",
 		"appname", l.params.Globals.Appname,
 		"version", l.params.Globals.Version,
-		"arch", runtime.GOARCH,
+		"buildarch", l.params.Globals.Buildarch,
 	)
 }

internal/logger/logger_test.go

@@ -1,34 +0,0 @@
-package logger //nolint:testpackage // sets the unexported log and params fields
-
-import (
-	"bytes"
-	"encoding/json"
-	"log/slog"
-	"runtime"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"sneak.berlin/go/upaas/internal/globals"
-)
-
-func TestIdentifyLogsArchitectureFromRuntime(t *testing.T) {
-	t.Parallel()
-
-	var buf bytes.Buffer
-
-	l := &Logger{
-		log: slog.New(slog.NewJSONHandler(&buf, nil)),
-		params: Params{
-			Globals: &globals.Globals{Appname: "upaas-test", Version: "test"},
-		},
-	}
-
-	l.Identify()
-
-	var line map[string]any
-
-	require.NoError(t, json.Unmarshal(buf.Bytes(), &line))
-	assert.Equal(t, runtime.GOARCH, line["arch"])
-}