Wrap the top bar's buttons onto a second row when narrow (closes #272)

The top bar's two sides were held apart only by justify-between, with
no gap and no wrapping, so at 390 px "by @sneak" ended where the New
App button began. The bar's row now wraps and has a gap: in a window
too narrow for one row, New App and Logout move to a second row; on
wider windows the bar looks as before.

Model: opus-5-5

.dockerignore

@@ -1,8 +1,35 @@
 # .git is sent so that `make build` in the Dockerfile can stamp the commit into
 # upaas. List no tracked file here: git would see it as deleted in the build and
 # the version would end in -dirty.
-.env
-bin/
-.vscode/
-.idea/
-*.test
+
+# The patterns of .gitignore; **/ makes Docker match them in every directory.
+**/.DS_Store
+**/Thumbs.db
+**/*.swp
+**/*.swo
+**/*~
+**/*.bak
+**/.idea/
+**/.vscode/
+**/*.sublime-*
+**/node_modules/
+**/.env
+**/.env.*
+**/*.pem
+**/*.key
+**/bin/
+**/*.exe
+**/*.exe~
+**/*.dll
+**/*.so
+**/*.dylib
+**/*.test
+**/*.out
+/data/
+
+# Git never applies its ignore patterns inside .git; send all of it again.
+!.git/**
+
+# .git is sent without its config, because a remote URL there can carry a
+# credential; `git describe` does not need it. Keep this after !.git/**.
+.git/config

.gitignore

@@ -1,3 +1,5 @@
+# .dockerignore repeats these patterns; change both together.
+
 # OS
 .DS_Store
 Thumbs.db
@@ -29,3 +31,6 @@ bin/
 *.dylib
 *.test
 *.out
+
+# upaasd's data directory when it runs from the checkout (UPAAS_DATA_DIR default)
+/data/

CONVENTIONS.md

@@ -117,13 +117,11 @@ import (
 var (
     Appname string = "CHANGEME"
     Version string
-    Buildarch string
 )
 
 func main() {
     globals.Appname = Appname
     globals.Version = Version
-    globals.Buildarch = Buildarch
 
     fx.New(
         fx.Provide(
@@ -823,7 +821,7 @@ func (l *Logger) Identify() {
     l.log.Info("starting",
         "appname", l.params.Globals.Appname,
         "version", l.params.Globals.Version,
-        "buildarch", l.params.Globals.Buildarch,
+        "arch", runtime.GOARCH,
     )
 }
 ```
@@ -945,20 +943,17 @@ import "go.uber.org/fx"
 var (
     Appname string
     Version string
-    Buildarch string
 )
 
 // Struct for DI
 type Globals struct {
     Appname string
     Version string
-    Buildarch string
 }
 
 func New(lc fx.Lifecycle) (*Globals, error) {
     n := &Globals{
         Appname: Appname,
-        Buildarch: Buildarch,
         Version: Version,
     }
     return n, nil
@@ -972,13 +967,11 @@ func New(lc fx.Lifecycle) (*Globals, error) {
 var (
     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
     // ...
 }
 ```
@@ -989,10 +982,9 @@ 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=$(VERSION) -X main.Buildarch=$(BUILDARCH)" ./cmd/httpd
+    go build -ldflags "-X main.Version=$(VERSION)" ./cmd/httpd
 ```
 
 ---

Makefile

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

README.md

@@ -278,9 +278,6 @@ exist yet, upaas has Docker create it as an empty directory, owned by root, when
 the app's container starts; there is no need to create it first. An existing
 host path is left as it is. This needs Docker Engine 23.0 or later.
 
-A deploy or rollback replaces the app's container with a new one, which keeps
-only the files the app wrote to its volume mounts.
-
 ## License
 
 WTFPL

TODO.md

@@ -20,10 +20,59 @@ regress.
 
 # Completed Steps
 
-- 2026-10-01: An app with no volume mounts says on its page, and in the log of
-  each deploy, that a deploy or rollback loses the files it writes and a restart
-  keeps them; the README's Volume mounts section says a deploy or rollback keeps
-  only the files the app wrote to its volume mounts (#248).
+- 2026-10-02: In a window too narrow for the top bar, such as 390 px, the New
+  App and Logout buttons move to a second row instead of running into "by
+  @sneak"; the bar keeps a gap between its two sides at every width (#272).
+
+- 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: On the Applications list, a long repository URL now wraps within
+  its column instead of making the table wider than its card, which cut off the
+  Actions column and the Deploy buttons. In a window too narrow for the table,
+  the card scrolls sideways instead of cutting the table off (#262).
+
+- 2026-10-02: `docker build .` no longer sends git-ignored files, such as
+  `.env.local`, `*.key` files or upaasd's `data/` directory with its session
+  key, into the build stages and the build cache: `.dockerignore` now leaves out
+  everything `.gitignore` does, and `data/` is git-ignored (#266).
+
+- 2026-10-02: `.dockerignore` leaves out `.git/config`, so a remote URL there
+  that carries a credential no longer goes into the Docker build; the image
+  still shows the commit it was built from (#269).
+
+- 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).
+
+- 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
+  commit gives its tag to the new image; the old one is kept while the app runs
+  it or Rollback would start it, then removed by its ID, found among the images
+  the app's deployments recorded. The removal of old images now keeps every
+  image any app runs or would roll back to. A deployment's commit is now saved
+  when it is updated, so manual deploys keep the commit read from the clone
+  (#239).
+
+- 2026-10-01: Two database writes at the same moment no longer fail with
+  "database is locked": each transaction now takes the write lock when it begins
+  and waits up to 5 seconds for another writer to finish (#253).
+
+- 2026-10-01: The hint under the app page's environment variable editor now says
+  changes take effect at the next deploy or rollback, in the page's warning
+  style, instead of asking for a container restart, which keeps the old values
+  (#255).
+
+- 2026-10-01: Builds attach a BuildKit session, as the docker command line does,
+  so a base image that is not on the host is pulled instead of the build failing
+  with "no active sessions" on Docker Engine 27. Container logs, and so the
+  clone output in the build log and the app logs, no longer carry Docker's
+  stream frame headers, and the commit is now read from the clone output (#251).
 
 - 2026-10-01: An app's first deploy no longer fails when a volume's host path
   does not exist yet: upaas asks Docker to create a missing host path when the

cmd/upaasd/main.go

@@ -27,13 +27,11 @@ import (
 var (
 	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(

go.mod

@@ -4,6 +4,7 @@ go 1.25
 
 require (
 	github.com/99designs/basicauth-go v0.0.0-20230316000542-bf6f9cbbf0f8
+	github.com/distribution/reference v0.6.0
 	github.com/docker/docker v27.3.1+incompatible
 	github.com/docker/go-connections v0.6.0
 	github.com/go-chi/chi/v5 v5.2.3
@@ -39,7 +40,6 @@ require (
 	github.com/containerd/ttrpc v1.2.5 // indirect
 	github.com/containerd/typeurl/v2 v2.2.0 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
-	github.com/distribution/reference v0.6.0 // indirect
 	github.com/docker/go-units v0.5.0 // indirect
 	github.com/felixge/httpsnoop v1.0.4 // indirect
 	github.com/fsnotify/fsnotify v1.9.0 // indirect

internal/database/database.go

@@ -137,8 +137,11 @@ func (d *Database) connect(ctx context.Context) error {
 		return fmt.Errorf("failed to create data directory: %w", err)
 	}
 
-	// Open database with WAL mode and foreign keys
-	dsn := dbPath + "?_journal_mode=WAL&_foreign_keys=on"
+	// Open database with WAL mode and foreign keys. Transactions take the
+	// write lock when they begin and wait up to 5s for another writer,
+	// instead of failing with "database is locked" when both write.
+	dsn := dbPath + "?_journal_mode=WAL&_foreign_keys=on" +
+		"&_txlock=immediate&_busy_timeout=5000"
 
 	database, err := sql.Open("sqlite3", dsn)
 	if err != nil {

internal/docker/client.go

@@ -3,12 +3,14 @@ package docker
 
 import (
 	"bufio"
+	"bytes"
 	"context"
 	"encoding/json"
 	"errors"
 	"fmt"
 	"io"
 	"log/slog"
+	"net"
 	"os"
 	"path/filepath"
 	"regexp"
@@ -25,9 +27,11 @@ import (
 	"github.com/docker/docker/client"
 	"github.com/docker/docker/pkg/archive"
 	"github.com/docker/docker/pkg/jsonmessage"
+	"github.com/docker/docker/pkg/stdcopy"
 	"github.com/docker/go-connections/nat"
 	controlapi "github.com/moby/buildkit/api/services/control"
 	buildkitclient "github.com/moby/buildkit/client"
+	"github.com/moby/buildkit/session"
 	"github.com/moby/buildkit/util/progress/progressui"
 	"go.uber.org/fx"
 
@@ -388,12 +392,17 @@ func (c *Client) ContainerLogs(
 		}
 	}()
 
-	logs, err := io.ReadAll(reader)
+	// A container without a terminal, as all of upaas's are, sends its
+	// output in frames, each with a header naming stdout or stderr. Both
+	// go to one buffer, in the order they were written.
+	var logs bytes.Buffer
+
+	_, err = stdcopy.StdCopy(&logs, &logs, reader)
 	if err != nil {
 		return "", fmt.Errorf("failed to read container logs: %w", err)
 	}
 
-	return string(logs), nil
+	return logs.String(), nil
 }
 
 // IsContainerRunning checks if a container is running.
@@ -496,6 +505,7 @@ type cloneConfig struct {
 type CloneResult struct {
 	Output    string // Combined stdout/stderr from git clone
 	CommitSHA string // The HEAD commit SHA after clone/checkout
+	ShortSHA  string // git's short form of CommitSHA (git rev-parse --short)
 }
 
 // CloneRepo clones a git repository using SSH and optionally checks out a
@@ -558,7 +568,7 @@ func (c *Client) RemoveImage(ctx context.Context, imageID ImageID) error {
 }
 
 // ListImageTags returns the tags in the given repository, such as
-// "upaas-myapp:12" in "upaas-myapp", each with the ID of its image.
+// "upaas-myapp:1a2b3c4" in "upaas-myapp", each with the ID of its image.
 // Tags the same image has in other repositories are left out.
 func (c *Client) ListImageTags(
 	ctx context.Context,
@@ -588,19 +598,44 @@ func (c *Client) ListImageTags(
 	return tags, nil
 }
 
-// RemoveImageTag removes a tag such as "upaas-myapp:12", without force.
-// Docker then deletes the image, and the untagged images it was built on,
-// only if no other tag and no container still uses it.
-func (c *Client) RemoveImageTag(ctx context.Context, tag string) error {
+// ListUntaggedImages returns the IDs of the images that have no tag, such
+// as one whose tag a later build gave to the image it built.
+func (c *Client) ListUntaggedImages(ctx context.Context) ([]ImageID, error) {
+	if c.docker == nil {
+		return nil, ErrNotConnected
+	}
+
+	images, err := c.docker.ImageList(ctx, image.ListOptions{
+		Filters: filters.NewArgs(filters.Arg("dangling", "true")),
+	})
+	if err != nil {
+		return nil, fmt.Errorf("failed to list untagged images: %w", err)
+	}
+
+	imageIDs := make([]ImageID, 0, len(images))
+
+	for _, img := range images {
+		imageIDs = append(imageIDs, ImageID(img.ID))
+	}
+
+	return imageIDs, nil
+}
+
+// RemoveImageTag removes the tag name, such as "upaas-myapp:1a2b3c4",
+// without force. Docker then deletes the image, and the untagged images it
+// was built on, only if no other tag and no container still uses it. If name
+// is instead the ID of an untagged image, it removes that image unless a
+// container uses it.
+func (c *Client) RemoveImageTag(ctx context.Context, name string) error {
 	if c.docker == nil {
 		return ErrNotConnected
 	}
 
-	_, err := c.docker.ImageRemove(ctx, tag, image.RemoveOptions{
+	_, err := c.docker.ImageRemove(ctx, name, image.RemoveOptions{
 		PruneChildren: true,
 	})
 	if err != nil && !client.IsErrNotFound(err) {
-		return fmt.Errorf("failed to remove image tag %s: %w", tag, err)
+		return fmt.Errorf("failed to remove image %s: %w", name, err)
 	}
 
 	return nil
@@ -637,11 +672,24 @@ func (c *Client) performBuild(
 		}
 	}()
 
+	buildSession, err := c.startBuildSession(ctx)
+	if err != nil {
+		return "", err
+	}
+
+	defer func() {
+		closeErr := buildSession.Close()
+		if closeErr != nil {
+			c.log.Error("failed to close build session", "error", closeErr)
+		}
+	}()
+
 	// Build with BuildKit: the stages of a multi-stage build are kept in
 	// its build cache, which Docker limits on its own, instead of being
 	// left behind as untagged images.
 	resp, err := c.docker.ImageBuild(ctx, tarArchive, dockertypes.ImageBuildOptions{
 		Version:    dockertypes.BuilderBuildKit,
+		SessionID:  buildSession.ID(),
 		Dockerfile: opts.DockerfilePath,
 		Tags:       opts.Tags,
 		Remove:     true,
@@ -677,6 +725,34 @@ func (c *Client) performBuild(
 	return "", nil
 }
 
+// startBuildSession attaches a BuildKit session to the daemon, as the docker
+// command line does for a build. BuildKit asks the client, over the session,
+// for registry access to fetch a base image that is not on the host; without
+// a session, Docker Engine 27 fails the build with "no active sessions". The
+// shared key is only used for a build context sent over the session; upaas
+// sends the context with the build request. The caller closes the session.
+func (c *Client) startBuildSession(ctx context.Context) (*session.Session, error) {
+	buildSession, err := session.NewSession(ctx, "")
+	if err != nil {
+		return nil, fmt.Errorf("failed to create build session: %w", err)
+	}
+
+	go func() {
+		runErr := buildSession.Run(ctx, func(
+			ctx context.Context,
+			proto string,
+			meta map[string][]string,
+		) (net.Conn, error) {
+			return c.docker.DialHijack(ctx, "/session", proto, meta)
+		})
+		if runErr != nil {
+			c.log.Error("build session failed", "error", runErr)
+		}
+	}()
+
+	return buildSession, nil
+}
+
 // scannerInitialBufferSize is the initial buffer size for the build log scanner.
 const scannerInitialBufferSize = 64 * 1024 // 64KB
 
@@ -855,11 +931,13 @@ func (c *Client) createGitContainer(
 		// Clone without depth limit so we can checkout any commit, then checkout specific SHA
 		script = `git clone --branch "$CLONE_BRANCH" "$CLONE_URL" /repo` +
 			` && cd /repo && git checkout "$CLONE_SHA"` +
-			` && echo COMMIT:$(git rev-parse HEAD)`
+			` && echo COMMIT:$(git rev-parse HEAD)` +
+			` && echo SHORT_SHA:$(git rev-parse --short HEAD)`
 	} else {
 		// Shallow clone of branch HEAD, then output commit SHA
 		script = `git clone --depth 1 --branch "$CLONE_BRANCH" "$CLONE_URL" /repo` +
-			` && cd /repo && echo COMMIT:$(git rev-parse HEAD)`
+			` && cd /repo && echo COMMIT:$(git rev-parse HEAD)` +
+			` && echo SHORT_SHA:$(git rev-parse --short HEAD)`
 	}
 
 	env := []string{
@@ -937,23 +1015,37 @@ func (c *Client) runGitClone(
 			)
 		}
 
-		// Parse commit SHA from output (looks for "COMMIT:<sha>" line)
-		commitSHA := parseCommitSHA(logs)
+		// Parse the commit from the "COMMIT:" and "SHORT_SHA:" lines.
+		result := &CloneResult{
+			Output:    logs,
+			CommitSHA: parseCommitSHA(logs, commitMarker),
+			ShortSHA:  parseCommitSHA(logs, shortSHAMarker),
+		}
 
-		return &CloneResult{Output: logs, CommitSHA: commitSHA}, nil
+		// The short hash names the image the deploy builds.
+		if result.ShortSHA == "" {
+			return nil, fmt.Errorf("%w: no short commit hash in its output: %s",
+				ErrGitCloneFailed, logs)
+		}
+
+		return result, nil
 	}
 }
 
-// commitMarker is the prefix used to identify commit SHA in clone output.
-const commitMarker = "COMMIT:"
+// Prefixes of the lines in the clone output that carry the commit checked
+// out, in full and in git's short form.
+const (
+	commitMarker   = "COMMIT:"
+	shortSHAMarker = "SHORT_SHA:"
+)
 
-// parseCommitSHA extracts the commit SHA from git clone output.
-// It looks for a line starting with "COMMIT:" and returns the SHA after it.
-func parseCommitSHA(output string) string {
+// parseCommitSHA extracts a commit SHA from git clone output.
+// It looks for a line starting with marker and returns the SHA after it.
+func parseCommitSHA(output, marker string) string {
 	for line := range strings.SplitSeq(output, "\n") {
 		line = strings.TrimSpace(line)
 
-		sha, found := strings.CutPrefix(line, commitMarker)
+		sha, found := strings.CutPrefix(line, marker)
 		if found {
 			return strings.TrimSpace(sha)
 		}

internal/docker/validation_test.go

@@ -6,6 +6,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"io"
 	"log/slog"
 	"net/http"
 	"net/http/httptest"
@@ -15,7 +16,9 @@ import (
 	"testing"
 	"time"
 
+	"github.com/docker/docker/api/types/container"
 	"github.com/docker/docker/client"
+	"github.com/docker/docker/pkg/stdcopy"
 	controlapi "github.com/moby/buildkit/api/services/control"
 )
 
@@ -203,6 +206,8 @@ func TestPerformCloneRemovesContainerVolumes(t *testing.T) {
 						<-r.Context().Done()
 					case strings.HasSuffix(r.URL.Path, "/wait"):
 						_, _ = fmt.Fprintf(w, `{"StatusCode":%d}`, tt.exitCode)
+					case strings.HasSuffix(r.URL.Path, "/logs"):
+						writeCloneOutput(w)
 					default:
 						_, _ = w.Write([]byte(`{}`))
 					}
@@ -219,18 +224,7 @@ func TestPerformCloneRemovesContainerVolumes(t *testing.T) {
 
 			c := &Client{docker: dockerAPI, log: slog.Default()}
 
-			dir := t.TempDir()
-			cfg := &cloneConfig{
-				repoURL:       "git@example.com:repo.git",
-				branch:        mainBranch,
-				sshPrivateKey: "fake-key",
-				containerDir:  filepath.Join(dir, "repo"),
-				hostDir:       filepath.Join(dir, "repo"),
-				keyFile:       filepath.Join(dir, "deploy_key"),
-				hostKeyFile:   filepath.Join(dir, "deploy_key"),
-			}
-
-			_, _ = c.performClone(ctx, cfg)
+			_, _ = c.performClone(ctx, testCloneConfig(t))
 
 			select {
 			case query := <-removeQuery:
@@ -244,6 +238,38 @@ func TestPerformCloneRemovesContainerVolumes(t *testing.T) {
 	}
 }
 
+// testCloneConfig returns the settings of a clone in these tests, with its
+// files in a temporary directory.
+func testCloneConfig(t *testing.T) *cloneConfig {
+	t.Helper()
+
+	dir := t.TempDir()
+
+	return &cloneConfig{
+		repoURL:       "git@example.com:repo.git",
+		branch:        mainBranch,
+		sshPrivateKey: "fake-key",
+		containerDir:  filepath.Join(dir, "repo"),
+		hostDir:       filepath.Join(dir, "repo"),
+		keyFile:       filepath.Join(dir, "deploy_key"),
+		hostKeyFile:   filepath.Join(dir, "deploy_key"),
+	}
+}
+
+// cloneCommit is the commit the fake clones in these tests check out.
+const cloneCommit = "1a2b3c4d5e6f7a8b9c0d1e2f3a4b5c6d7e8f9a0b"
+
+// writeCloneOutput writes the output of a git clone of cloneCommit as
+// Docker sends a container's log: each line after a header.
+func writeCloneOutput(w io.Writer) {
+	stdout := stdcopy.NewStdWriter(w, stdcopy.Stdout)
+	stderr := stdcopy.NewStdWriter(w, stdcopy.Stderr)
+
+	_, _ = stderr.Write([]byte("Cloning into '/repo'...\n"))
+	_, _ = stdout.Write([]byte("COMMIT:" + cloneCommit + "\n"))
+	_, _ = stdout.Write([]byte("SHORT_SHA:1a2b3c4\n"))
+}
+
 // TestPerformBuildUsesBuildKit runs a build against a fake Docker API and
 // checks that it asks for BuildKit and that BuildKit's progress reaches the
 // build log as plain text.
@@ -273,6 +299,8 @@ func TestPerformBuildUsesBuildKit(t *testing.T) {
 			switch {
 			case strings.HasSuffix(r.URL.Path, "/version"):
 				_, _ = w.Write([]byte(`{"Version":"27.3.1","ApiVersion":"1.47"}`))
+			case strings.HasSuffix(r.URL.Path, "/session"):
+				serveSession(t, w, r, make(chan string, 1))
 			case strings.HasSuffix(r.URL.Path, "/build"):
 				if r.URL.Query().Get("version") != "2" {
 					http.Error(w, "not a BuildKit build", http.StatusBadRequest)
@@ -367,6 +395,8 @@ func TestPerformBuildFails(t *testing.T) {
 					case strings.HasSuffix(r.URL.Path, "/version"):
 						_, _ = fmt.Fprintf(w, `{"Version":%q,"ApiVersion":%q}`,
 							tt.engine, tt.apiVersion)
+					case strings.HasSuffix(r.URL.Path, "/session"):
+						serveSession(t, w, r, make(chan string, 1))
 					case strings.HasSuffix(r.URL.Path, "/build"):
 						_, _ = w.Write([]byte(tt.buildOutput))
 					default:
@@ -395,3 +425,258 @@ func TestPerformBuildFails(t *testing.T) {
 		})
 	}
 }
+
+// TestPerformBuildAttachesSession runs a build against a fake Docker API
+// that, like the real daemon, fails the build with "no active sessions"
+// unless the build names a session the client attached over the session
+// endpoint. It also checks that the session is closed when the build ends.
+func TestPerformBuildAttachesSession(t *testing.T) {
+	t.Parallel()
+
+	attached := make(chan string, 1)
+	sessionClosed := make(chan struct{})
+
+	srv := httptest.NewServer(http.HandlerFunc(
+		func(w http.ResponseWriter, r *http.Request) {
+			switch {
+			case strings.HasSuffix(r.URL.Path, "/version"):
+				_, _ = w.Write([]byte(`{"Version":"27.3.1","ApiVersion":"1.47"}`))
+			case strings.HasSuffix(r.URL.Path, "/session"):
+				serveSession(t, w, r, attached)
+				close(sessionClosed)
+			case strings.HasSuffix(r.URL.Path, "/build"):
+				id := r.URL.Query().Get("session")
+				attachedID := ""
+
+				// The daemon waits a few seconds for the build's session
+				// to attach.
+				if id != "" {
+					select {
+					case attachedID = <-attached:
+					case <-time.After(5 * time.Second):
+					}
+				}
+
+				if id == "" || attachedID != id {
+					_, _ = w.Write([]byte(`{"errorDetail":{"message":"no active sessions"},` +
+						`"error":"no active sessions"}`))
+				}
+			default:
+				t.Errorf("unexpected request to %s", r.URL.Path)
+			}
+		},
+	))
+	t.Cleanup(srv.Close)
+
+	dockerAPI, err := client.NewClientWithOpts(
+		client.WithHost("tcp://" + srv.Listener.Addr().String()),
+	)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	c := &Client{docker: dockerAPI, log: slog.Default()}
+
+	_, err = c.performBuild(t.Context(), BuildImageOptions{ContextDir: t.TempDir()})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	select {
+	case <-sessionClosed:
+	case <-time.After(5 * time.Second):
+		t.Error("the build's session was not closed when the build ended")
+	}
+}
+
+// serveSession answers a request to attach a session as the Docker daemon
+// does: it switches the connection over to the session, sends the session's
+// ID on attached, and holds the connection until the client closes it.
+func serveSession(
+	t *testing.T,
+	w http.ResponseWriter,
+	r *http.Request,
+	attached chan<- string,
+) {
+	t.Helper()
+
+	conn, _, err := http.NewResponseController(w).Hijack()
+	if err != nil {
+		t.Error(err)
+
+		return
+	}
+
+	defer func() { _ = conn.Close() }()
+
+	_, err = io.WriteString(conn, "HTTP/1.1 101 Switching Protocols\r\n"+
+		"Connection: Upgrade\r\nUpgrade: h2c\r\n\r\n")
+	if err != nil {
+		t.Error(err)
+
+		return
+	}
+
+	attached <- r.Header.Get("X-Docker-Expose-Session-Uuid")
+
+	_, _ = io.Copy(io.Discard, conn)
+}
+
+// TestPerformCloneReadsFramedLogs runs a clone against a fake Docker API that
+// sends the clone container's output in frames, as Docker does for a
+// container without a terminal, and checks that the output comes back as
+// plain text and that the commit, in full and in git's short form, is read
+// from it.
+func TestPerformCloneReadsFramedLogs(t *testing.T) {
+	t.Parallel()
+
+	srv := httptest.NewServer(http.HandlerFunc(
+		func(w http.ResponseWriter, r *http.Request) {
+			w.Header().Set("Content-Type", "application/json")
+
+			switch {
+			case strings.HasSuffix(r.URL.Path, "/containers/create"):
+				_, _ = w.Write([]byte(`{"Id":"gitcontainer"}`))
+			case strings.HasSuffix(r.URL.Path, "/wait"):
+				_, _ = w.Write([]byte(`{"StatusCode":0}`))
+			case strings.HasSuffix(r.URL.Path, "/logs"):
+				writeCloneOutput(w)
+			default:
+				_, _ = w.Write([]byte(`{}`))
+			}
+		},
+	))
+	t.Cleanup(srv.Close)
+
+	dockerAPI, err := client.NewClientWithOpts(
+		client.WithHost("tcp://" + srv.Listener.Addr().String()),
+	)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	c := &Client{docker: dockerAPI, log: slog.Default()}
+
+	result, err := c.performClone(t.Context(), testCloneConfig(t))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	want := "Cloning into '/repo'...\nCOMMIT:" + cloneCommit + "\nSHORT_SHA:1a2b3c4\n"
+	if result.Output != want {
+		t.Errorf("got clone output %q, want %q", result.Output, want)
+	}
+
+	if result.CommitSHA != cloneCommit || result.ShortSHA != "1a2b3c4" {
+		t.Errorf("got commit %q, short %q", result.CommitSHA, result.ShortSHA)
+	}
+}
+
+// TestPerformCloneFailsWithoutShortSHA runs a clone against a fake Docker API
+// whose clone succeeds but prints no "SHORT_SHA:" line, and checks that the
+// clone fails, since the short hash names the image the deploy builds.
+func TestPerformCloneFailsWithoutShortSHA(t *testing.T) {
+	t.Parallel()
+
+	srv := httptest.NewServer(http.HandlerFunc(
+		func(w http.ResponseWriter, r *http.Request) {
+			w.Header().Set("Content-Type", "application/json")
+
+			switch {
+			case strings.HasSuffix(r.URL.Path, "/containers/create"):
+				_, _ = w.Write([]byte(`{"Id":"gitcontainer"}`))
+			case strings.HasSuffix(r.URL.Path, "/wait"):
+				_, _ = w.Write([]byte(`{"StatusCode":0}`))
+			case strings.HasSuffix(r.URL.Path, "/logs"):
+				_, _ = stdcopy.NewStdWriter(w, stdcopy.Stdout).
+					Write([]byte("COMMIT:" + cloneCommit + "\n"))
+			default:
+				_, _ = w.Write([]byte(`{}`))
+			}
+		},
+	))
+	t.Cleanup(srv.Close)
+
+	dockerAPI, err := client.NewClientWithOpts(
+		client.WithHost("tcp://" + srv.Listener.Addr().String()),
+	)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	c := &Client{docker: dockerAPI, log: slog.Default()}
+
+	_, err = c.performClone(t.Context(), testCloneConfig(t))
+	if !errors.Is(err, ErrGitCloneFailed) {
+		t.Errorf("got error %v, want %v", err, ErrGitCloneFailed)
+	}
+}
+
+// TestPerformCloneAsksGitForShortSHA runs a clone of a branch's last commit
+// and a clone of a given commit against a fake Docker API, and checks that
+// the command each clone container is created with prints git's own short
+// form of the commit checked out.
+func TestPerformCloneAsksGitForShortSHA(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name      string
+		commitSHA string
+	}{
+		{name: "branch", commitSHA: ""},
+		{name: "commit", commitSHA: cloneCommit},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+
+			created := make(chan container.Config, 1)
+
+			srv := httptest.NewServer(http.HandlerFunc(
+				func(w http.ResponseWriter, r *http.Request) {
+					w.Header().Set("Content-Type", "application/json")
+
+					switch {
+					case strings.HasSuffix(r.URL.Path, "/containers/create"):
+						var cfg container.Config
+
+						_ = json.NewDecoder(r.Body).Decode(&cfg)
+						created <- cfg
+
+						_, _ = w.Write([]byte(`{"Id":"gitcontainer"}`))
+					case strings.HasSuffix(r.URL.Path, "/wait"):
+						_, _ = w.Write([]byte(`{"StatusCode":0}`))
+					case strings.HasSuffix(r.URL.Path, "/logs"):
+						writeCloneOutput(w)
+					default:
+						_, _ = w.Write([]byte(`{}`))
+					}
+				},
+			))
+			t.Cleanup(srv.Close)
+
+			dockerAPI, err := client.NewClientWithOpts(
+				client.WithHost("tcp://" + srv.Listener.Addr().String()),
+			)
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			c := &Client{docker: dockerAPI, log: slog.Default()}
+
+			cfg := testCloneConfig(t)
+			cfg.commitSHA = tt.commitSHA
+
+			_, err = c.performClone(t.Context(), cfg)
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			cmd := strings.Join((<-created).Cmd, " ")
+			if !strings.Contains(cmd, "echo SHORT_SHA:$(git rev-parse --short HEAD)") {
+				t.Errorf("clone command %q does not print git's short hash", cmd)
+			}
+		})
+	}
+}

internal/globals/globals.go

@@ -15,14 +15,12 @@ var (
 	mu      sync.RWMutex
 	appname string
 	version string
-	buildarch string
 )
 
 // Globals holds build-time variables for dependency injection.
 type Globals struct {
 	Appname string
 	Version string
-	Buildarch string
 }
 
 // New creates a new Globals instance from package-level variables.
@@ -33,7 +31,6 @@ func New(_ fx.Lifecycle) (*Globals, error) {
 	return &Globals{
 		Appname: appname,
 		Version: version,
-		Buildarch: buildarch,
 	}, nil
 }
 
@@ -52,11 +49,3 @@ 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.go

@@ -21,7 +21,6 @@ import (
 	"sneak.berlin/go/upaas/internal/database"
 	"sneak.berlin/go/upaas/internal/models"
 	"sneak.berlin/go/upaas/internal/service/app"
-	"sneak.berlin/go/upaas/internal/service/deploy"
 	"sneak.berlin/go/upaas/templates"
 )
 
@@ -195,7 +194,6 @@ func (h *Handlers) HandleAppDetail() http.HandlerFunc {
 			"EnvVars":          envVars,
 			"Labels":           labels,
 			"Volumes":          volumes,
-			"NoVolumesWarning": deploy.NoVolumesWarning,
 			"Ports":            ports,
 			"Deployments":      deployments,
 			"LatestDeployment": latestDeployment,

internal/handlers/app_name_validation.go

@@ -13,12 +13,15 @@ const (
 	appNameMaxLength = 63
 )
 
-// validAppNameRe matches names containing only lowercase alphanumeric characters and
-// hyphens, starting and ending with an alphanumeric character.
-var validAppNameRe = regexp.MustCompile(`^[a-z0-9][a-z0-9-]*[a-z0-9]$`)
+// validAppNameRe matches runs of lowercase letters and digits joined by
+// single dots or by hyphens, such as "my-app" or "sneak.berlin". Docker
+// accepts every name it allows as the app's image name, upaas-<name>; a
+// dot needs a letter or digit on both sides because Docker requires it.
+// It also keeps the name from being "." or ".." or starting or ending
+// with a dot, so it is safe as a directory and file name. The pattern
+// attribute of the name field on the new and edit app forms is the same.
+var validAppNameRe = regexp.MustCompile(`^[a-z0-9]+((\.|-+)[a-z0-9]+)*$`)
 
-// validateAppName checks that the given app name is safe for use in Docker
-// container names, image tags, and file system paths.
 var (
 	errAppNameLength = errors.New(
 		"app name must be between " +
@@ -26,11 +29,14 @@ var (
 			strconv.Itoa(appNameMaxLength) + " characters",
 	)
 	errAppNamePattern = errors.New(
-		"app name must contain only lowercase letters, numbers, " +
-			"and hyphens, and must start and end with a letter or number",
+		"app name must contain only lowercase letters, numbers, hyphens, " +
+			"and dots, must start and end with a letter or number, " +
+			"and must have a letter or number on both sides of each dot",
 	)
 )
 
+// validateAppName checks that the given app name is safe for use in Docker
+// container names, image tags, and file system paths.
 func validateAppName(name string) error {
 	if len(name) < appNameMinLength || len(name) > appNameMaxLength {
 		return errAppNameLength

internal/handlers/app_name_validation_test.go

@@ -1,7 +1,16 @@
 package handlers //nolint:testpackage // testing unexported validateAppName
 
 import (
+	"bytes"
+	"strconv"
+	"strings"
 	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"sneak.berlin/go/upaas/internal/models"
+	"sneak.berlin/go/upaas/templates"
 )
 
 func TestValidateAppName(t *testing.T) {
@@ -18,6 +27,10 @@ func TestValidateAppName(t *testing.T) {
 		{"valid two chars", "ab", false},
 		{"valid complex", "my-cool-app-v2", false},
 		{"valid all numbers", "123", false},
+		{"valid double hyphen", "my--app", false},
+		{"valid domain", "sneak.berlin", false},
+		{"valid two dots", "www.sneak.berlin", false},
+		{"valid dot and hyphen", "my-app.example.com", false},
 		{"empty", "", true},
 		{"single char", "a", true},
 		{"too long", "a" + string(make([]byte, 63)), true},
@@ -36,7 +49,12 @@ func TestValidateAppName(t *testing.T) {
 		{"starts with hyphen", "-myapp", true},
 		{"ends with hyphen", "myapp-", true},
 		{"underscore", "my_app", true},
-		{"dot", "my.app", true},
+		{"two dots in a row", "a..b", true},
+		{"starts with dot", ".a", true},
+		{"ends with dot", "a.", true},
+		{"only dots", "..", true},
+		{"hyphen before dot", "a-.b", true},
+		{"hyphen after dot", "a.-b", true},
 		{"slash", "my/app", true},
 		{"path traversal", "../etc/passwd", true},
 		{"special chars", "app@name!", true},
@@ -54,3 +72,42 @@ func TestValidateAppName(t *testing.T) {
 		})
 	}
 }
+
+func TestValidateAppNameErrorMentionsDots(t *testing.T) {
+	t.Parallel()
+
+	err := validateAppName("a..b")
+
+	require.ErrorIs(t, err, errAppNamePattern)
+	assert.Contains(t, err.Error(), "dots")
+}
+
+// TestAppFormsCheckAppNameLikeServer checks that the name field on the new
+// and edit app forms has the server's pattern and length limits, and that
+// its hint mentions dots.
+func TestAppFormsCheckAppNameLikeServer(t *testing.T) {
+	t.Parallel()
+
+	pattern := strings.TrimSuffix(strings.TrimPrefix(validAppNameRe.String(), "^"), "$")
+
+	pages := map[string]map[string]any{
+		"app_new.html":  {},
+		"app_edit.html": {dataKeyApp: &models.App{}},
+	}
+
+	for page, data := range pages {
+		var out bytes.Buffer
+
+		require.NoError(t, templates.GetParsed().ExecuteTemplate(&out, page, data))
+
+		// The name field and its hint, up to the end of their div.
+		_, field, found := strings.Cut(out.String(), `id="name"`)
+		require.True(t, found, page)
+
+		field, _, _ = strings.Cut(field, "</div>")
+		assert.Contains(t, field, `pattern="`+pattern+`"`, page)
+		assert.Contains(t, field, `minlength="`+strconv.Itoa(appNameMinLength)+`"`, page)
+		assert.Contains(t, field, `maxlength="`+strconv.Itoa(appNameMaxLength)+`"`, page)
+		assert.Contains(t, field, "hyphens, and dots", page)
+	}
+}

internal/handlers/app_no_volumes_test.go

@@ -1,45 +0,0 @@
-package handlers_test
-
-import (
-	"net/http"
-	"net/http/httptest"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"sneak.berlin/go/upaas/internal/models"
-	"sneak.berlin/go/upaas/internal/service/deploy"
-)
-
-// TestAppPageSaysFilesAreLostOnlyWhenAppHasNoVolumes checks that the app page
-// shows deploy.NoVolumesWarning until the app gets a volume mount.
-func TestAppPageSaysFilesAreLostOnlyWhenAppHasNoVolumes(t *testing.T) {
-	t.Parallel()
-
-	testCtx := setupTestHandlers(t)
-	createdApp := createTestApp(t, testCtx, "no-volumes-app")
-
-	renderAppPage := func() string {
-		request := httptest.NewRequestWithContext(
-			t.Context(), http.MethodGet, "/apps/"+createdApp.ID, nil,
-		)
-		request = addChiURLParams(request, map[string]string{"id": createdApp.ID})
-		recorder := httptest.NewRecorder()
-
-		testCtx.handlers.HandleAppDetail().ServeHTTP(recorder, request)
-		require.Equal(t, http.StatusOK, recorder.Code)
-
-		return recorder.Body.String()
-	}
-
-	assert.Contains(t, renderAppPage(), deploy.NoVolumesWarning)
-
-	volume := models.NewVolume(testCtx.database)
-	volume.AppID = createdApp.ID
-	volume.HostPath = "/srv/no-volumes-app"
-	volume.ContainerPath = "/data"
-	require.NoError(t, volume.Save(t.Context()))
-
-	assert.NotContains(t, renderAppPage(), deploy.NoVolumesWarning)
-}

internal/handlers/app_page_env_var_hint_test.go

@@ -0,0 +1,39 @@
+package handlers_test
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"sneak.berlin/go/upaas/internal/service/app"
+)
+
+// TestAppPageEnvVarHint checks that the environment variable editor says
+// changes take effect at the next deploy or rollback, in the warning style.
+func TestAppPageEnvVarHint(t *testing.T) {
+	t.Parallel()
+
+	testCtx := setupTestHandlers(t)
+
+	createdApp, err := testCtx.appSvc.CreateApp(t.Context(), app.CreateAppInput{
+		Name:    "env-hint-app",
+		RepoURL: "git@example.com:user/env-hint-app.git",
+	})
+	require.NoError(t, err)
+
+	request := httptest.NewRequestWithContext(
+		t.Context(), http.MethodGet, "/apps/"+createdApp.ID, nil,
+	)
+	request = addChiURLParams(request, map[string]string{"id": createdApp.ID})
+	recorder := httptest.NewRecorder()
+
+	testCtx.handlers.HandleAppDetail().ServeHTTP(recorder, request)
+
+	require.Equal(t, http.StatusOK, recorder.Code)
+	assert.Contains(t, recorder.Body.String(),
+		`<p class="alert-warning mt-1">`+
+			"Environment variable changes take effect at the next deploy or rollback.</p>")
+}

internal/handlers/dashboard_layout_test.go

@@ -0,0 +1,77 @@
+package handlers_test
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"sneak.berlin/go/upaas/internal/service/app"
+)
+
+// TestDashboardTableFitsCard checks that the card around the app table
+// scrolls sideways instead of hiding what does not fit, and that a long
+// repository URL wraps instead of pushing the action buttons out.
+func TestDashboardTableFitsCard(t *testing.T) {
+	t.Parallel()
+
+	testCtx := setupTestHandlers(t)
+
+	repoURL := "https://git.example.com/user/" +
+		"a-repository-name-long-enough-to-push-the-action-buttons-out.git"
+
+	_, err := testCtx.appSvc.CreateApp(t.Context(), app.CreateAppInput{
+		Name:    "long-url-app",
+		RepoURL: repoURL,
+	})
+	require.NoError(t, err)
+
+	request := httptest.NewRequestWithContext(t.Context(), http.MethodGet, "/", nil)
+	recorder := httptest.NewRecorder()
+
+	testCtx.handlers.HandleDashboard().ServeHTTP(recorder, request)
+
+	require.Equal(t, http.StatusOK, recorder.Code)
+
+	body := recorder.Body.String()
+
+	beforeTable, _, found := strings.Cut(body, `<table class="table">`)
+	require.True(t, found, "dashboard has no app table")
+
+	cardTag := beforeTable[strings.LastIndex(beforeTable, "<div"):]
+	assert.Contains(t, cardTag, "overflow-x-auto")
+	assert.NotContains(t, cardTag, "overflow-hidden")
+
+	beforeURL, _, found := strings.Cut(body, ">"+repoURL+"</td>")
+	require.True(t, found, "dashboard has no repository cell")
+
+	cellTag := beforeURL[strings.LastIndex(beforeURL, "<td"):]
+	assert.Contains(t, cellTag, "whitespace-normal")
+	assert.Contains(t, cellTag, "break-all")
+}
+
+// TestTopBarWrapsWhenNarrow checks that the top bar keeps a gap between the
+// µPaaS title and the New App and Logout buttons, and puts the buttons on a
+// second row in a window too narrow for one, instead of letting them meet.
+func TestTopBarWrapsWhenNarrow(t *testing.T) {
+	t.Parallel()
+
+	testCtx := setupTestHandlers(t)
+
+	request := httptest.NewRequestWithContext(t.Context(), http.MethodGet, "/", nil)
+	recorder := httptest.NewRecorder()
+
+	testCtx.handlers.HandleDashboard().ServeHTTP(recorder, request)
+
+	require.Equal(t, http.StatusOK, recorder.Code)
+
+	_, afterNav, found := strings.Cut(recorder.Body.String(), `<nav class="app-bar">`)
+	require.True(t, found, "dashboard has no top bar")
+
+	rowTag, _, _ := strings.Cut(strings.TrimSpace(afterNav), ">")
+	assert.Contains(t, rowTag, "flex-wrap")
+	assert.Contains(t, rowTag, "gap-")
+}

internal/logger/logger.go

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

internal/logger/logger_test.go

@@ -0,0 +1,34 @@
+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"])
+}

internal/models/deployment.go

@@ -203,11 +203,12 @@ func (d *Deployment) insert(ctx context.Context) error {
 func (d *Deployment) update(ctx context.Context) error {
 	query := `
 		UPDATE deployments SET
-			image_id = ?, container_id = ?, status = ?, logs = ?, finished_at = ?
+			commit_sha = ?, image_id = ?, container_id = ?, status = ?, logs = ?,
+			finished_at = ?
 		WHERE id = ?`
 
 	_, err := d.db.Exec(ctx, query,
-		d.ImageID, d.ContainerID, d.Status, d.Logs, d.FinishedAt, d.ID,
+		d.CommitSHA, d.ImageID, d.ContainerID, d.Status, d.Logs, d.FinishedAt, d.ID,
 	)
 
 	return err
@@ -295,6 +296,45 @@ func FindDeploymentsByAppID(
 	return deployments, nil
 }
 
+// FindDeploymentImageIDs returns the IDs of the images an app's
+// deployments built or rolled back to.
+func FindDeploymentImageIDs(
+	ctx context.Context,
+	deployDB *database.Database,
+	appID string,
+) ([]string, error) {
+	rows, err := deployDB.Query(ctx, `
+		SELECT DISTINCT image_id FROM deployments
+		WHERE app_id = ? AND image_id IS NOT NULL`,
+		appID,
+	)
+	if err != nil {
+		return nil, fmt.Errorf("querying deployment image IDs: %w", err)
+	}
+
+	defer func() { _ = rows.Close() }()
+
+	var imageIDs []string
+
+	for rows.Next() {
+		var imageID string
+
+		scanErr := rows.Scan(&imageID)
+		if scanErr != nil {
+			return nil, fmt.Errorf("scanning deployment image ID: %w", scanErr)
+		}
+
+		imageIDs = append(imageIDs, imageID)
+	}
+
+	rowsErr := rows.Err()
+	if rowsErr != nil {
+		return nil, fmt.Errorf("iterating deployment image IDs: %w", rowsErr)
+	}
+
+	return imageIDs, nil
+}
+
 // LatestDeploymentForApp finds the most recent deployment for an app.
 //
 //nolint:nilnil // returning nil,nil is idiomatic for "not found" in Active Record

internal/models/models_test.go

@@ -564,6 +564,33 @@ func TestDeploymentMarkFinished(t *testing.T) {
 	assert.True(t, found.FinishedAt.Valid)
 }
 
+// TestDeploymentSaveStoresCommitSetAfterInsert checks that a commit set on a
+// deployment after it was first saved, as a manual deploy does once the clone
+// reads it, is stored by the next save.
+func TestDeploymentSaveStoresCommitSetAfterInsert(t *testing.T) {
+	t.Parallel()
+
+	testDB, cleanup := setupTestDB(t)
+	defer cleanup()
+
+	app := createTestApp(t, testDB)
+
+	deployment := models.NewDeployment(testDB)
+	deployment.AppID = app.ID
+
+	err := deployment.Save(context.Background())
+	require.NoError(t, err)
+
+	deployment.CommitSHA = sql.NullString{String: "abc123def456", Valid: true}
+
+	err = deployment.Save(context.Background())
+	require.NoError(t, err)
+
+	found, err := models.FindDeployment(context.Background(), testDB, deployment.ID)
+	require.NoError(t, err)
+	assert.Equal(t, "abc123def456", found.CommitSHA.String)
+}
+
 func TestDeploymentFindByAppID(t *testing.T) {
 	t.Parallel()
 

internal/service/deploy/deploy.go

@@ -56,12 +56,6 @@ var (
 	ErrNoPreviousImage = errors.New("no previous image available for rollback")
 )
 
-// NoVolumesWarning is shown on the page of an app with no volume mounts and
-// written into each of its deploy logs.
-const NoVolumesWarning = "This app has no volume mounts, so the files it writes " +
-	"are lost whenever a deploy or rollback replaces its container; " +
-	"a restart of the container keeps them."
-
 // logFlushInterval is how often to flush buffered logs to the database.
 const logFlushInterval = time.Second
 
@@ -375,11 +369,6 @@ func (svc *Service) Deploy(
 
 	svc.logWebhookPayload(bgCtx, deployment, webhookEvent)
 
-	volumes, err := app.GetVolumes(bgCtx)
-	if err == nil && len(volumes) == 0 {
-		_ = deployment.AppendLog(bgCtx, NoVolumesWarning)
-	}
-
 	err = svc.updateAppStatusBuilding(bgCtx, app)
 	if err != nil {
 		return err
@@ -746,44 +735,103 @@ func (svc *Service) recordDeployedImage(
 	return nil
 }
 
-// removeUnusedImages removes the app's tags (upaas-<app>:<deployment>, set by
-// buildImage) except those of the image the running container uses and the
-// one Rollback would start. Docker deletes an image only once no other tag,
-// such as another app's, and no container still uses it.
+// removeUnusedImages removes the app's images except those an app's running
+// container uses or its Rollback would start. Docker deletes a tagged image
+// only once no other tag, such as another app's, and no container still
+// uses it.
 func (svc *Service) removeUnusedImages(
 	ctx context.Context,
 	app *models.App,
 	deployment *models.Deployment,
 ) {
-	tags, err := svc.docker.ListImageTags(ctx, "upaas-"+app.Name)
+	images, err := svc.findAppImages(ctx, app)
 	if err != nil {
 		svc.log.Error("failed to list app images", "error", err, "app", app.Name)
 
 		return
 	}
 
-	for _, tag := range slices.Sorted(maps.Keys(tags)) {
-		imageID := tags[tag].String()
-		if imageID == app.ImageID.String || imageID == app.PreviousImageID.String {
+	keep, err := svc.imagesToKeep(ctx)
+	if err != nil {
+		svc.log.Error("failed to list the images apps use", "error", err, "app", app.Name)
+
+		return
+	}
+
+	for _, name := range slices.Sorted(maps.Keys(images)) {
+		if keep[images[name].String()] {
 			continue
 		}
 
-		removeErr := svc.docker.RemoveImageTag(ctx, tag)
+		removeErr := svc.docker.RemoveImageTag(ctx, name)
 		if removeErr != nil {
 			svc.log.Error("failed to remove old image",
-				"error", removeErr, "app", app.Name, "tag", tag)
+				"error", removeErr, "app", app.Name, "image", name)
 			_ = deployment.AppendLog(
 				ctx,
-				"WARNING: failed to remove old image "+tag+": "+removeErr.Error(),
+				"WARNING: failed to remove old image "+name+": "+removeErr.Error(),
 			)
 
 			continue
 		}
 
-		_ = deployment.AppendLog(ctx, "Removed old image: "+tag)
+		_ = deployment.AppendLog(ctx, "Removed old image: "+name)
 	}
 }
 
+// findAppImages returns the app's images, each under the name it is removed
+// by: its tag, upaas-<app>:<short hash> as set by buildImage, or its ID if
+// it has none. A redeploy of a commit gives the commit's tag to the new
+// image, so the old one is found among the images the app's deployments
+// recorded.
+func (svc *Service) findAppImages(
+	ctx context.Context,
+	app *models.App,
+) (map[string]docker.ImageID, error) {
+	images, err := svc.docker.ListImageTags(ctx, "upaas-"+app.Name)
+	if err != nil {
+		return nil, fmt.Errorf("failed to list image tags: %w", err)
+	}
+
+	untagged, err := svc.docker.ListUntaggedImages(ctx)
+	if err != nil {
+		return nil, fmt.Errorf("failed to list untagged images: %w", err)
+	}
+
+	recorded, err := models.FindDeploymentImageIDs(ctx, svc.db, app.ID)
+	if err != nil {
+		return nil, fmt.Errorf("failed to find deployment images: %w", err)
+	}
+
+	for _, imageID := range untagged {
+		if slices.Contains(recorded, imageID.String()) {
+			images[imageID.String()] = imageID
+		}
+	}
+
+	return images, nil
+}
+
+// imagesToKeep returns the IDs of the image each app's running container
+// uses and the one its Rollback would start. It covers every app because
+// apps that build the same commit can share an image, and a redeploy can
+// take the tag that kept the image for one of them.
+func (svc *Service) imagesToKeep(ctx context.Context) (map[string]bool, error) {
+	apps, err := models.AllApps(ctx, svc.db)
+	if err != nil {
+		return nil, fmt.Errorf("failed to list apps: %w", err)
+	}
+
+	keep := make(map[string]bool)
+
+	for _, app := range apps {
+		keep[app.ImageID.String] = true
+		keep[app.PreviousImageID.String] = true
+	}
+
+	return keep, nil
+}
+
 // cleanupCancelledDeploy removes orphan resources left by a cancelled deployment.
 func (svc *Service) cleanupCancelledDeploy(
 	ctx context.Context,
@@ -923,14 +971,14 @@ func (svc *Service) buildImage(
 	app *models.App,
 	deployment *models.Deployment,
 ) (docker.ImageID, error) {
-	workDir, cleanup, err := svc.cloneRepository(ctx, app, deployment)
+	workDir, shortSHA, cleanup, err := svc.cloneRepository(ctx, app, deployment)
 	if err != nil {
 		return "", err
 	}
 
 	defer cleanup()
 
-	imageTag := fmt.Sprintf("upaas-%s:%d", app.Name, deployment.ID)
+	imageTag := "upaas-" + app.Name + ":" + shortSHA
 
 	// Create log writer that flushes build output to deployment logs every second
 	logWriter := newDeploymentLogWriter(ctx, deployment)
@@ -965,11 +1013,14 @@ func (svc *Service) buildImage(
 	return imageID, nil
 }
 
+// cloneRepository clones the app's repository for a build. It returns the
+// directory of the clone, git's short form of the commit checked out, and a
+// function that removes the clone.
 func (svc *Service) cloneRepository(
 	ctx context.Context,
 	app *models.App,
 	deployment *models.Deployment,
-) (string, func(), error) {
+) (string, string, func(), error) {
 	// Use a subdirectory of DataDir for builds since it's mounted from the host
 	// and accessible to Docker for bind mounts (unlike /tmp inside the container).
 	// Structure: builds/<appname>/<deployment-id>-<random>/
@@ -986,7 +1037,7 @@ func (svc *Service) cloneRepository(
 			fmt.Errorf("failed to create builds dir: %w", err),
 		)
 
-		return "", nil, fmt.Errorf("failed to create builds dir: %w", err)
+		return "", "", nil, fmt.Errorf("failed to create builds dir: %w", err)
 	}
 
 	buildDir, err := os.MkdirTemp(appBuildsDir, fmt.Sprintf("%d-*", deployment.ID))
@@ -998,7 +1049,7 @@ func (svc *Service) cloneRepository(
 			fmt.Errorf("failed to create temp dir: %w", err),
 		)
 
-		return "", nil, fmt.Errorf("failed to create temp dir: %w", err)
+		return "", "", nil, fmt.Errorf("failed to create temp dir: %w", err)
 	}
 
 	cleanup := func() { _ = os.RemoveAll(buildDir) }
@@ -1034,7 +1085,7 @@ func (svc *Service) cloneRepository(
 			fmt.Errorf("failed to clone repo: %w", cloneErr),
 		)
 
-		return "", nil, fmt.Errorf("failed to clone repo: %w", cloneErr)
+		return "", "", nil, fmt.Errorf("failed to clone repo: %w", cloneErr)
 	}
 
 	svc.processCloneResult(ctx, app, deployment, cloneResult, commitSHA)
@@ -1042,7 +1093,7 @@ func (svc *Service) cloneRepository(
 	// Return the 'work' subdirectory where the repo was cloned
 	workDir := filepath.Join(buildDir, "work")
 
-	return workDir, cleanup, nil
+	return workDir, cloneResult.ShortSHA, cleanup, nil
 }
 
 // processCloneResult handles the result of a git clone operation.

internal/service/deploy/deploy_app_name_test.go

@@ -0,0 +1,121 @@
+package deploy_test
+
+import (
+	"context"
+	"log/slog"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"os"
+	"slices"
+	"strings"
+	"testing"
+
+	"github.com/distribution/reference"
+	"github.com/docker/docker/daemon/names"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"sneak.berlin/go/upaas/internal/database"
+	"sneak.berlin/go/upaas/internal/globals"
+	"sneak.berlin/go/upaas/internal/handlers"
+	"sneak.berlin/go/upaas/internal/logger"
+	"sneak.berlin/go/upaas/internal/models"
+	"sneak.berlin/go/upaas/internal/service/app"
+)
+
+// TestDeployAppWithDotInName creates an app named sneak.berlin through the
+// new app form, as a user does, then builds and deploys it against a fake
+// Docker API and checks that Docker accepts the names of the image it
+// builds and of the container it runs, using Docker's own rules for each.
+func TestDeployAppWithDotInName(t *testing.T) {
+	t.Parallel()
+
+	api := &fakeImageAPI{
+		images:   map[string][]string{},
+		shortSHA: "abc1234",
+		nextID:   "sha256:built",
+	}
+	svc, db := newImageTestService(t, api)
+	ctx := context.Background()
+
+	createdApp := createAppWithForm(t, db, "sneak.berlin")
+
+	deployment := models.NewDeployment(db)
+	deployment.AppID = createdApp.ID
+	require.NoError(t, deployment.Save(ctx))
+
+	imageID, err := svc.BuildImage(ctx, createdApp, deployment)
+	require.NoError(t, err)
+	require.NoError(t, svc.DeployContainer(ctx, createdApp, deployment, imageID))
+
+	images, _ := api.state()
+
+	api.mu.Lock()
+	containers := slices.Clone(api.containers)
+	api.mu.Unlock()
+
+	require.Equal(t, map[string][]string{
+		"sha256:built": {"upaas-sneak.berlin:abc1234"},
+	}, images)
+
+	_, err = reference.ParseNormalizedNamed("upaas-sneak.berlin:abc1234")
+	require.NoError(t, err)
+
+	require.Equal(t, []string{"upaas-sneak.berlin"}, containers)
+	assert.Regexp(t, names.RestrictedNamePattern, containers[0])
+
+	assert.DirExists(t, svc.GetBuildDirExported(createdApp.Name))
+}
+
+// createAppWithForm posts the new app form with the given name, which
+// checks the name as it does for a user, and returns the app it created.
+func createAppWithForm(
+	t *testing.T,
+	db *database.Database,
+	name string,
+) *models.App {
+	t.Helper()
+
+	log := logger.NewForTest(slog.New(slog.NewTextHandler(os.Stderr, nil)))
+
+	appSvc, err := app.New(nil, app.ServiceParams{Logger: log, Database: db})
+	require.NoError(t, err)
+
+	globalInstance, err := globals.New(nil)
+	require.NoError(t, err)
+
+	handlersInstance, err := handlers.New(nil, handlers.Params{
+		Logger:   log,
+		Globals:  globalInstance,
+		Database: db,
+		App:      appSvc,
+	})
+	require.NoError(t, err)
+
+	form := url.Values{
+		"name":     {name},
+		"repo_url": {"git@example.com:sneak/" + name + ".git"},
+	}
+	request := httptest.NewRequestWithContext(
+		t.Context(), http.MethodPost, "/apps", strings.NewReader(form.Encode()),
+	)
+	request.Header.Set("Content-Type", "application/x-www-form-urlencoded")
+
+	recorder := httptest.NewRecorder()
+
+	handlersInstance.HandleAppCreate().ServeHTTP(recorder, request)
+
+	// The form redirects to the new app's page; it shows the form again,
+	// with the error, when it refuses the name.
+	require.Equal(t, http.StatusSeeOther, recorder.Code, recorder.Body.String())
+
+	appID, found := strings.CutPrefix(recorder.Header().Get("Location"), "/apps/")
+	require.True(t, found)
+
+	createdApp, err := models.FindApp(t.Context(), db, appID)
+	require.NoError(t, err)
+	require.NotNil(t, createdApp)
+
+	return createdApp
+}

internal/service/deploy/deploy_build_test.go

@@ -34,6 +34,8 @@ func TestBuildImageLogsBuildErrorBeforeDeployError(t *testing.T) {
 			switch {
 			case strings.HasSuffix(r.URL.Path, "/containers/create"):
 				_, _ = w.Write([]byte(`{"Id":"gitcontainer"}`))
+			case strings.HasSuffix(r.URL.Path, "/logs"):
+				writeCloneOutput(w, "abc1234")
 			case strings.HasSuffix(r.URL.Path, "/version"):
 				_, _ = w.Write([]byte(`{"Version":"27.3.1","ApiVersion":"1.47"}`))
 			case strings.HasSuffix(r.URL.Path, "/build"):
@@ -77,7 +79,7 @@ func TestBuildImageLogsBuildErrorBeforeDeployError(t *testing.T) {
 
 	// The service has no notify service: the app has no ntfy topic and no
 	// Slack webhook, so the build failure notification sends nothing.
-	svc := deploy.NewTestServiceWithConfig(log, cfg, dockerClient)
+	svc := deploy.NewTestServiceWithConfig(log, cfg, db, dockerClient)
 
 	_, err = svc.BuildImage(ctx, app, deployment)
 	require.EqualError(t, err, "failed to build image: exit code: 1")

internal/service/deploy/deploy_cleanup_test.go

@@ -20,7 +20,7 @@ func TestCleanupCancelledDeploy_RemovesBuildDir(t *testing.T) {
 	tmpDir := t.TempDir()
 	cfg := &config.Config{DataDir: tmpDir}
 
-	svc := deploy.NewTestServiceWithConfig(slog.Default(), cfg, nil)
+	svc := deploy.NewTestServiceWithConfig(slog.Default(), cfg, nil, nil)
 
 	// Create a fake build directory matching the deployment pattern
 	appName := "test-app"
@@ -59,7 +59,7 @@ func TestCleanupCancelledDeploy_NoBuildDir(t *testing.T) {
 	tmpDir := t.TempDir()
 	cfg := &config.Config{DataDir: tmpDir}
 
-	svc := deploy.NewTestServiceWithConfig(slog.Default(), cfg, nil)
+	svc := deploy.NewTestServiceWithConfig(slog.Default(), cfg, nil, nil)
 
 	// Should not panic when build dir doesn't exist
 	svc.CleanupCancelledDeploy(context.Background(), "nonexistent-app", 1, "")

internal/service/deploy/deploy_images_test.go

@@ -3,14 +3,21 @@ package deploy_test
 import (
 	"context"
 	"database/sql"
+	"encoding/json"
+	"fmt"
+	"io"
 	"log/slog"
+	"maps"
 	"net/http"
 	"net/http/httptest"
 	"os"
+	"slices"
 	"strings"
 	"sync"
 	"testing"
 
+	"github.com/docker/docker/api/types/image"
+	"github.com/docker/docker/pkg/stdcopy"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"go.uber.org/fx/fxtest"
@@ -23,45 +30,145 @@ import (
 	"sneak.berlin/go/upaas/internal/service/deploy"
 )
 
-// TestRecordDeployedImageRemovesOldImages runs the step after a deploy
-// against a fake Docker API. Image one is also tagged for another app,
-// image two was the previous image, three the current one, four is new.
-func TestRecordDeployedImageRemovesOldImages(t *testing.T) {
-	t.Parallel()
-
-	var (
+// fakeImageAPI is a fake Docker API that keeps images and their tags as
+// Docker does: a build gives its tag to the image it builds, and removing
+// an image's last tag, or an untagged image by its ID, deletes the image.
+// It also answers the steps of a git clone that reports shortSHA.
+type fakeImageAPI struct {
 	mu         sync.Mutex
-		removed []string
-		forced  bool
-	)
+	images     map[string][]string // image ID -> tags
+	shortSHA   string              // the commit's short hash the clone reports
+	nextID     string              // ID of the image the next build creates
+	removed    []string            // each tag or ID removed
+	forced     bool                // whether a removal was forced
+	containers []string            // name of each named container created
+}
+
+func (api *fakeImageAPI) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	api.mu.Lock()
+	defer api.mu.Unlock()
 
-	srv := httptest.NewServer(http.HandlerFunc(
-		func(w http.ResponseWriter, r *http.Request) {
 	w.Header().Set("Content-Type", "application/json")
 
+	_, name, isImage := strings.Cut(r.URL.Path, "/images/")
+
 	switch {
-			case r.Method == http.MethodDelete:
-				_, name, _ := strings.Cut(r.URL.Path, "/images/")
-
-				mu.Lock()
-
-				removed = append(removed, name)
-				forced = forced || r.URL.Query().Get("force") != ""
-				mu.Unlock()
-
-				_, _ = w.Write([]byte(`[]`))
 	case strings.HasSuffix(r.URL.Path, "/images/json"):
-				_, _ = w.Write([]byte(`[
-					{"Id":"sha256:one","RepoTags":["upaas-myapp:1","upaas-otherapp:7"]},
-					{"Id":"sha256:two","RepoTags":["upaas-myapp:2"]},
-					{"Id":"sha256:three","RepoTags":["upaas-myapp:3"]},
-					{"Id":"sha256:four","RepoTags":["upaas-myapp:4"]}
-				]`))
+		dangling := strings.Contains(r.URL.Query().Get("filters"), "dangling")
+		api.listImages(w, dangling)
+	case isImage && r.Method == http.MethodDelete:
+		api.forced = api.forced || r.URL.Query().Get("force") != ""
+		api.removeImage(w, name)
+	case isImage && strings.HasSuffix(name, "/json"):
+		api.inspectImage(w, strings.TrimSuffix(name, "/json"))
+	case strings.HasSuffix(r.URL.Path, "/build"):
+		tag := r.URL.Query().Get("t")
+		api.untag(tag)
+		api.images[api.nextID] = append(api.images[api.nextID], tag)
+	case strings.HasSuffix(r.URL.Path, "/version"):
+		_, _ = w.Write([]byte(`{"Version":"27.3.1","ApiVersion":"1.47"}`))
+	case strings.HasSuffix(r.URL.Path, "/containers/create"):
+		// The git clone's container has no name; the app's has.
+		if containerName := r.URL.Query().Get("name"); containerName != "" {
+			api.containers = append(api.containers, containerName)
+		}
+
+		_, _ = w.Write([]byte(`{"Id":"gitcontainer"}`))
+	case strings.HasSuffix(r.URL.Path, "/logs"):
+		writeCloneOutput(w, api.shortSHA)
 	default:
+		// The other steps of the git clone, which succeeds.
 		_, _ = w.Write([]byte(`{}`))
 	}
-		},
-	))
+}
+
+// listImages lists the untagged images, or else the tagged ones.
+func (api *fakeImageAPI) listImages(w http.ResponseWriter, dangling bool) {
+	list := []image.Summary{}
+
+	for _, id := range slices.Sorted(maps.Keys(api.images)) {
+		if (len(api.images[id]) == 0) == dangling {
+			list = append(list, image.Summary{ID: id, RepoTags: api.images[id]})
+		}
+	}
+
+	data, err := json.Marshal(list)
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+
+		return
+	}
+
+	_, _ = w.Write(data)
+}
+
+func (api *fakeImageAPI) inspectImage(w http.ResponseWriter, name string) {
+	for id, tags := range api.images {
+		if id == name || slices.Contains(tags, name) {
+			_, _ = fmt.Fprintf(w, `{"Id":%q}`, id)
+
+			return
+		}
+	}
+
+	w.WriteHeader(http.StatusNotFound)
+	_, _ = w.Write([]byte(`{"message":"No such image"}`))
+}
+
+func (api *fakeImageAPI) removeImage(w http.ResponseWriter, name string) {
+	api.removed = append(api.removed, name)
+
+	id := name
+	if _, isID := api.images[name]; !isID {
+		id = api.untag(name)
+	}
+
+	if len(api.images[id]) == 0 {
+		delete(api.images, id)
+	}
+
+	_, _ = w.Write([]byte(`[]`))
+}
+
+// untag removes tag from the image that has it, leaving the image, and
+// returns the image's ID.
+func (api *fakeImageAPI) untag(tag string) string {
+	for id, tags := range api.images {
+		if slices.Contains(tags, tag) {
+			api.images[id] = slices.DeleteFunc(tags, func(t string) bool { return t == tag })
+
+			return id
+		}
+	}
+
+	return ""
+}
+
+// state returns each image's tags and each tag or ID removed.
+func (api *fakeImageAPI) state() (map[string][]string, []string) {
+	api.mu.Lock()
+	defer api.mu.Unlock()
+
+	return maps.Clone(api.images), slices.Clone(api.removed)
+}
+
+// writeCloneOutput writes the line of a git clone's output that gives the
+// commit's short hash, as Docker sends a container's log: after a header.
+func writeCloneOutput(w io.Writer, shortSHA string) {
+	out := stdcopy.NewStdWriter(w, stdcopy.Stdout)
+
+	_, _ = fmt.Fprintf(out, "SHORT_SHA:%s\n", shortSHA)
+}
+
+// newImageTestService returns a deploy service that uses api as its
+// Docker API, and its database.
+func newImageTestService(
+	t *testing.T,
+	api *fakeImageAPI,
+) (*deploy.Service, *database.Database) {
+	t.Helper()
+
+	srv := httptest.NewServer(api)
 	t.Cleanup(srv.Close)
 
 	log := slog.New(slog.NewTextHandler(os.Stderr, nil))
@@ -77,30 +184,203 @@ func TestRecordDeployedImageRemovesOldImages(t *testing.T) {
 	t.Cleanup(lifecycle.RequireStop)
 
 	db := database.NewTestDatabase(t)
-	ctx := context.Background()
+	dataDir := t.TempDir()
+	cfg := &config.Config{DataDir: dataDir, HostDataDir: dataDir}
+
+	return deploy.NewTestServiceWithConfig(log, cfg, db, dockerClient), db
+}
+
+// saveApp saves an app with the given current and previous image.
+func saveApp(
+	t *testing.T,
+	db *database.Database,
+	name, imageID, previousImageID string,
+) *models.App {
+	t.Helper()
 
 	app := models.NewApp(db)
-	app.ID = "myapp-id"
-	app.Name = "myapp"
-	app.ImageID = sql.NullString{String: "sha256:three", Valid: true}
-	app.PreviousImageID = sql.NullString{String: "sha256:two", Valid: true}
-	require.NoError(t, app.Save(ctx))
+	app.ID = name + "-id"
+	app.Name = name
+	app.ImageID = sql.NullString{String: imageID, Valid: true}
+	app.PreviousImageID = sql.NullString{String: previousImageID, Valid: true}
+	require.NoError(t, app.Save(context.Background()))
+
+	return app
+}
+
+// TestRecordDeployedImageRemovesOldImages runs the step after a deploy
+// against a fake Docker API. Image one has a tag from before images were
+// tagged with their commit, and is also tagged for another app. Image two
+// was the previous image, three the current one, four is new. Image five is
+// the other app's previous image, which a redeploy of its commit left
+// without the other app's tag.
+func TestRecordDeployedImageRemovesOldImages(t *testing.T) {
+	t.Parallel()
+
+	api := &fakeImageAPI{images: map[string][]string{
+		"sha256:one":   {"upaas-myapp:140", "upaas-otherapp:1a2b3c4"},
+		"sha256:two":   {"upaas-myapp:2b3c4d5"},
+		"sha256:three": {"upaas-myapp:3c4d5e6"},
+		"sha256:four":  {"upaas-myapp:4d5e6f7"},
+		"sha256:five":  {"upaas-myapp:5e6f7a8"},
+	}}
+	svc, db := newImageTestService(t, api)
+	ctx := context.Background()
+
+	app := saveApp(t, db, "myapp", "sha256:three", "sha256:two")
+	saveApp(t, db, "otherapp", "sha256:other", "sha256:five")
 
 	deployment := models.NewDeployment(db)
 	deployment.AppID = app.ID
 	require.NoError(t, deployment.Save(ctx))
 
-	svc := deploy.NewTestServiceWithConfig(log, &config.Config{}, dockerClient)
-
-	err = svc.RecordDeployedImage(ctx, app, deployment, "sha256:four")
+	err := svc.RecordDeployedImage(ctx, app, deployment, "sha256:four")
 	require.NoError(t, err)
 
 	assert.Equal(t, "sha256:four", app.ImageID.String)
 	assert.Equal(t, "sha256:three", app.PreviousImageID.String)
 
-	mu.Lock()
-	defer mu.Unlock()
+	images, removed := api.state()
 
-	assert.Equal(t, []string{"upaas-myapp:1", "upaas-myapp:2"}, removed)
-	assert.False(t, forced, "old image tags must be removed without force")
+	assert.Equal(t, []string{"upaas-myapp:140", "upaas-myapp:2b3c4d5"}, removed)
+	assert.Equal(t, map[string][]string{
+		"sha256:one":   {"upaas-otherapp:1a2b3c4"},
+		"sha256:three": {"upaas-myapp:3c4d5e6"},
+		"sha256:four":  {"upaas-myapp:4d5e6f7"},
+		"sha256:five":  {"upaas-myapp:5e6f7a8"},
+	}, images)
+	assert.False(t, api.forced, "old images must be removed without force")
+}
+
+// TestRecordDeployedImageRemovesOnlyTheAppsUntaggedImages runs the step after
+// a deploy against a fake Docker API that holds three untagged images: one an
+// earlier deployment of the app recorded, one a deployment of another app
+// recorded, and one no deployment recorded, such as an image upaas never
+// built. Only the app's own is removed.
+func TestRecordDeployedImageRemovesOnlyTheAppsUntaggedImages(t *testing.T) {
+	t.Parallel()
+
+	api := &fakeImageAPI{images: map[string][]string{
+		"sha256:new":      {"upaas-myapp:1a2b3c4"},
+		"sha256:myapp":    {},
+		"sha256:otherapp": {},
+		"sha256:unknown":  {},
+	}}
+	svc, db := newImageTestService(t, api)
+	ctx := context.Background()
+
+	app := saveApp(t, db, "myapp", "", "")
+	otherApp := saveApp(t, db, "otherapp", "", "")
+
+	saveDeployment := func(appID, imageID string) *models.Deployment {
+		t.Helper()
+
+		deployment := models.NewDeployment(db)
+		deployment.AppID = appID
+		deployment.ImageID = sql.NullString{String: imageID, Valid: true}
+		require.NoError(t, deployment.Save(ctx))
+
+		return deployment
+	}
+
+	saveDeployment(app.ID, "sha256:myapp")
+	saveDeployment(otherApp.ID, "sha256:otherapp")
+	deployment := saveDeployment(app.ID, "sha256:new")
+
+	err := svc.RecordDeployedImage(ctx, app, deployment, "sha256:new")
+	require.NoError(t, err)
+
+	images, removed := api.state()
+
+	assert.Equal(t, []string{"sha256:myapp"}, removed)
+	assert.Equal(t, map[string][]string{
+		"sha256:new":      {"upaas-myapp:1a2b3c4"},
+		"sha256:otherapp": {},
+		"sha256:unknown":  {},
+	}, images)
+}
+
+// TestRedeployRemovesImagesLeftWithoutTag deploys commits against a fake
+// Docker API, some of them again. A build takes the commit's tag from the
+// image an earlier build of it made. That image is kept, without a tag,
+// while the app runs it or Rollback would start it, and is removed by its
+// ID once neither does.
+func TestRedeployRemovesImagesLeftWithoutTag(t *testing.T) {
+	t.Parallel()
+
+	const (
+		tagABC1234   = "upaas-myapp:abc1234"
+		tag0123ABC   = "upaas-myapp:0123abc"
+		retriedImage = "sha256:retried-0123abc"
+	)
+
+	// The app runs commit abc1234 and would roll back to def5678. The last
+	// deploy, of commit 0123abc, failed after its build.
+	api := &fakeImageAPI{images: map[string][]string{
+		"sha256:built-abc1234":  {tagABC1234},
+		"sha256:built-def5678":  {"upaas-myapp:def5678"},
+		"sha256:failed-0123abc": {tag0123ABC},
+	}}
+	svc, db := newImageTestService(t, api)
+	ctx := context.Background()
+
+	app := saveApp(t, db, "myapp", "sha256:built-abc1234", "sha256:built-def5678")
+
+	for imageID := range api.images {
+		deployment := models.NewDeployment(db)
+		deployment.AppID = app.ID
+		deployment.ImageID = sql.NullString{String: imageID, Valid: true}
+		require.NoError(t, deployment.Save(ctx))
+	}
+
+	deployCommit := func(shortSHA, imageID string) {
+		t.Helper()
+
+		api.mu.Lock()
+		api.shortSHA = shortSHA
+		api.nextID = imageID
+		api.mu.Unlock()
+
+		deployment := models.NewDeployment(db)
+		deployment.AppID = app.ID
+		require.NoError(t, deployment.Save(ctx))
+
+		built, err := svc.BuildImage(ctx, app, deployment)
+		require.NoError(t, err)
+		require.NoError(t, svc.RecordDeployedImage(ctx, app, deployment, built))
+	}
+
+	// The failed deploy's image loses its tag, and nothing uses it.
+	deployCommit("0123abc", retriedImage)
+
+	images, _ := api.state()
+	assert.Equal(t, map[string][]string{
+		"sha256:built-abc1234": {tagABC1234},
+		retriedImage:           {tag0123ABC},
+	}, images)
+
+	// The running image loses its tag and becomes the one Rollback starts.
+	deployCommit("0123abc", "sha256:rebuilt-0123abc")
+
+	images, _ = api.state()
+	assert.Equal(t, map[string][]string{
+		"sha256:rebuilt-0123abc": {tag0123ABC},
+		retriedImage:             {},
+	}, images)
+	assert.Equal(t, retriedImage, app.PreviousImageID.String)
+
+	// Once Rollback no longer needs it, the untagged image is removed.
+	deployCommit("4567def", "sha256:built-4567def")
+
+	images, removed := api.state()
+	assert.Equal(t, map[string][]string{
+		"sha256:built-4567def":   {"upaas-myapp:4567def"},
+		"sha256:rebuilt-0123abc": {tag0123ABC},
+	}, images)
+	assert.Equal(t, []string{
+		"sha256:failed-0123abc", "upaas-myapp:def5678", // first deploy
+		tagABC1234,   // second deploy
+		retriedImage, // third deploy
+	}, removed)
+	assert.False(t, api.forced, "old images must be removed without force")
 }

internal/service/deploy/deploy_volumes_test.go

@@ -1,79 +0,0 @@
-package deploy_test
-
-import (
-	"context"
-	"log/slog"
-	"os"
-	"strings"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"sneak.berlin/go/upaas/internal/config"
-	"sneak.berlin/go/upaas/internal/database"
-	"sneak.berlin/go/upaas/internal/docker"
-	"sneak.berlin/go/upaas/internal/logger"
-	"sneak.berlin/go/upaas/internal/models"
-	"sneak.berlin/go/upaas/internal/service/deploy"
-	"sneak.berlin/go/upaas/internal/service/notify"
-)
-
-// deployLog deploys a new app, with one volume mount when withVolume is set,
-// and returns the deploy's log. Docker is not connected, so the deploy fails
-// at the git clone, after the start of its log is written.
-func deployLog(t *testing.T, withVolume bool) string {
-	t.Helper()
-
-	log := logger.NewForTest(slog.New(slog.NewTextHandler(os.Stderr, nil)))
-	dataDir := t.TempDir()
-	cfg := &config.Config{DataDir: dataDir, HostDataDir: dataDir}
-	db := database.NewTestDatabase(t)
-
-	dockerClient, err := docker.New(nil, docker.Params{Logger: log, Config: cfg})
-	require.NoError(t, err)
-
-	notifySvc, err := notify.New(nil, notify.ServiceParams{Logger: log})
-	require.NoError(t, err)
-
-	svc, err := deploy.New(nil, deploy.ServiceParams{
-		Logger: log, Config: cfg, Database: db,
-		Docker: dockerClient, Notify: notifySvc,
-	})
-	require.NoError(t, err)
-
-	ctx := context.Background()
-
-	app := models.NewApp(db)
-	app.ID = "volumesapp-id"
-	app.Name = "volumesapp"
-	app.Branch = "main"
-	require.NoError(t, app.Save(ctx))
-
-	if withVolume {
-		volume := models.NewVolume(db)
-		volume.AppID = app.ID
-		volume.HostPath = "/srv/volumesapp"
-		volume.ContainerPath = "/data"
-		require.NoError(t, volume.Save(ctx))
-	}
-
-	err = svc.Deploy(ctx, app, nil, false)
-	require.ErrorIs(t, err, docker.ErrNotConnected)
-
-	deployments, err := app.GetDeployments(ctx, 1)
-	require.NoError(t, err)
-	require.Len(t, deployments, 1)
-
-	return deployments[0].Logs.String
-}
-
-func TestDeployLogSaysFilesAreLostOnlyWhenAppHasNoVolumes(t *testing.T) {
-	t.Parallel()
-
-	logWithoutVolumes := deployLog(t, false)
-	assert.Equal(t, 1, strings.Count(logWithoutVolumes, deploy.NoVolumesWarning),
-		logWithoutVolumes)
-
-	assert.NotContains(t, deployLog(t, true), deploy.NoVolumesWarning)
-}

internal/service/deploy/export_test.go

@@ -9,6 +9,7 @@ import (
 	"strings"
 
 	"sneak.berlin/go/upaas/internal/config"
+	"sneak.berlin/go/upaas/internal/database"
 	"sneak.berlin/go/upaas/internal/docker"
 	"sneak.berlin/go/upaas/internal/models"
 )
@@ -44,15 +45,18 @@ func (svc *Service) UnlockApp(appID string) {
 	svc.unlockApp(appID)
 }
 
-// NewTestServiceWithConfig creates a Service with config and docker client for testing.
+// NewTestServiceWithConfig creates a Service with config, database and
+// docker client for testing.
 func NewTestServiceWithConfig(
 	log *slog.Logger,
 	cfg *config.Config,
+	db *database.Database,
 	dockerClient *docker.Client,
 ) *Service {
 	return &Service{
 		log:    log,
 		config: cfg,
+		db:     db,
 		docker: dockerClient,
 	}
 }
@@ -109,6 +113,16 @@ func (svc *Service) BuildImage(
 	return svc.buildImage(ctx, app, deployment)
 }
 
+// DeployContainer exposes deployContainerWithTimeout for testing.
+func (svc *Service) DeployContainer(
+	ctx context.Context,
+	app *models.App,
+	deployment *models.Deployment,
+	imageID docker.ImageID,
+) error {
+	return svc.deployContainerWithTimeout(ctx, app, deployment, imageID)
+}
+
 // BuildContainerOptionsExported exposes buildContainerOptions for testing.
 func (svc *Service) BuildContainerOptionsExported(
 	ctx context.Context,

templates/app_detail.html

@@ -178,7 +178,7 @@
                                     <button type="submit" class="btn-primary text-sm">Save</button>
                                     <button type="button" @click="editIdx = -1" class="text-gray-500 hover:text-gray-700 text-sm">Cancel</button>
                                 </form>
-                                <p class="text-xs text-amber-600 mt-1">⚠ Container restart needed after env var changes.</p>
+                                <p class="alert-warning mt-1">Environment variable changes take effect at the next deploy or rollback.</p>
                             </td>
                         </template>
                     </tr>
@@ -318,8 +318,6 @@
                 </tbody>
             </table>
         </div>
-        {{else}}
-        <p class="alert-warning">{{.NoVolumesWarning}}</p>
         {{end}}
         <form method="POST" action="/apps/{{.App.ID}}/volumes" class="flex flex-col sm:flex-row gap-2 items-end">
                 {{ .CSRFField }}

templates/app_edit.html

@@ -30,10 +30,12 @@
                     name="name"
                     value="{{.App.Name}}"
                     required
-                    pattern="[a-z0-9-]+"
+                    minlength="2"
+                    maxlength="63"
+                    pattern="[a-z0-9]+((\.|-+)[a-z0-9]+)*"
                     class="input"
                 >
-                <p class="text-sm text-gray-500 mt-1">Lowercase letters, numbers, and hyphens only</p>
+                <p class="text-sm text-gray-500 mt-1">Lowercase letters, numbers, hyphens, and dots, such as my-app or example.com</p>
             </div>
 
             <div class="form-group">

templates/app_new.html

@@ -30,11 +30,13 @@
                     name="name"
                     value="{{.Name}}"
                     required
-                    pattern="[a-z0-9-]+"
+                    minlength="2"
+                    maxlength="63"
+                    pattern="[a-z0-9]+((\.|-+)[a-z0-9]+)*"
                     class="input"
                     placeholder="my-app"
                 >
-                <p class="text-sm text-gray-500 mt-1">Lowercase letters, numbers, and hyphens only</p>
+                <p class="text-sm text-gray-500 mt-1">Lowercase letters, numbers, hyphens, and dots, such as my-app or example.com</p>
             </div>
 
             <div class="form-group">

templates/base.html

@@ -26,7 +26,7 @@
 
 {{define "nav"}}
 <nav class="app-bar">
-    <div class="max-w-6xl mx-auto flex justify-between items-center">
+    <div class="max-w-6xl mx-auto flex flex-wrap justify-between items-center gap-3">
         <div class="flex items-center gap-3">
             <a href="/" class="text-xl font-medium text-gray-900 hover:text-primary-600 transition-colors">µPaaS</a>
             <span class="text-sm text-gray-500">by <a href="https://sneak.berlin" class="text-primary-600 hover:text-primary-800">@sneak</a></span>

templates/dashboard.html

@@ -20,7 +20,7 @@
     </div>
 
     {{if .AppStats}}
-    <div class="card overflow-hidden">
+    <div class="card overflow-x-auto">
         <table class="table">
             <thead class="table-header">
                 <tr>
@@ -41,7 +41,7 @@
                             {{.App.Name}}
                         </a>
                     </td>
-                    <td class="text-gray-500 font-mono text-xs">{{.App.RepoURL}}</td>
+                    <td class="text-gray-500 font-mono text-xs whitespace-normal break-all">{{.App.RepoURL}}</td>
                     <td class="text-gray-500">{{.App.Branch}}</td>
                     <td>
                         {{if eq .App.Status "running"}}