TODO.md

@@ -20,6 +20,9 @@ regress.
 
 # Completed Steps
 
+- 2026-09-23: The git clone container is now removed together with its anonymous
+  volume (the `alpine/git` image declares one at `/git`), so a deploy no longer
+  leaves a Docker volume behind (#215).
 - 2026-09-23: Deployment log files are now stored under `logs/<appname>/`
   instead of `logs/<hostname>/<appname>/`, so downloads keep working after the
   upaas container is recreated; logs written under an old hostname directory are

internal/docker/client.go

@@ -656,11 +656,14 @@ func (c *Client) performClone(
 		return nil, err
 	}
 
+	// The git image declares a volume, so Docker gives each clone container
+	// an anonymous volume; remove it with the container. The removal must
+	// still run when the deploy is cancelled.
 	defer func() {
 		_ = c.docker.ContainerRemove(
-			ctx,
+			context.WithoutCancel(ctx),
 			gitContainerID.String(),
-			container.RemoveOptions{Force: true},
+			container.RemoveOptions{Force: true, RemoveVolumes: true},
 		)
 	}()
 

internal/docker/validation_test.go

@@ -1,9 +1,18 @@
 package docker //nolint:testpackage // tests unexported regexps and Client struct
 
 import (
+	"context"
 	"errors"
+	"fmt"
 	"log/slog"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"path/filepath"
+	"strings"
 	"testing"
+
+	"github.com/docker/docker/client"
 )
 
 // mainBranch is the branch name used across validation tests.
@@ -149,3 +158,84 @@ func TestCloneRepoRejectsInjection(t *testing.T) {
 		})
 	}
 }
+
+// TestPerformCloneRemovesContainerVolumes runs a clone against a fake Docker
+// API and checks that the clone container is removed together with its
+// anonymous volumes, whether the clone succeeds, fails, or is cancelled.
+func TestPerformCloneRemovesContainerVolumes(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name     string
+		exitCode int
+		cancel   bool
+	}{
+		{name: "succeeds", exitCode: 0},
+		{name: "fails", exitCode: 1},
+		{name: "cancelled", cancel: true},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+
+			ctx, cancel := context.WithCancel(t.Context())
+			t.Cleanup(cancel)
+
+			removeQuery := make(chan url.Values, 1)
+
+			srv := httptest.NewServer(http.HandlerFunc(
+				func(w http.ResponseWriter, r *http.Request) {
+					w.Header().Set("Content-Type", "application/json")
+
+					switch {
+					case r.Method == http.MethodDelete:
+						removeQuery <- r.URL.Query()
+					case strings.HasSuffix(r.URL.Path, "/containers/create"):
+						_, _ = w.Write([]byte(`{"Id":"gitcontainer"}`))
+					case strings.HasSuffix(r.URL.Path, "/wait") && tt.cancel:
+						// Cancel the deploy while the clone is running.
+						cancel()
+						<-r.Context().Done()
+					case strings.HasSuffix(r.URL.Path, "/wait"):
+						_, _ = fmt.Fprintf(w, `{"StatusCode":%d}`, tt.exitCode)
+					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()}
+
+			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)
+
+			select {
+			case query := <-removeQuery:
+				if query.Get("v") != "1" {
+					t.Errorf("clone container removed without its volumes: %v", query)
+				}
+			default:
+				t.Error("clone container was not removed")
+			}
+		})
+	}
+}