Reject backup jobs without paths

internal/server/http/jobs.go

@@ -69,6 +69,10 @@ func (s *Server) dispatchJob(ctx context.Context, user *store.User,
 		Kind: kind,
 		Args: args,
 	}
+	if kind == api.JobBackup && len(args) == 0 {
+		return res, stdhttp.StatusUnprocessableEntity, "backup_paths_required",
+			"backup requires paths in args; configured backups must use POST /api/hosts/{id}/source-groups/{gid}/run"
+	}
 	if kind == api.JobForget {
 		if !validForgetArgs(args) {
 			return res, stdhttp.StatusBadRequest, "invalid_args",

internal/server/http/jobs_test.go

@@ -14,6 +14,34 @@ import (
 	"gitea.dcglab.co.uk/steve/restic-manager/internal/store"
 )
 
+func TestRunNowBackupRejectsEmptyPaths(t *testing.T) {
+	t.Parallel()
+	_, ts, st := rawTestServer(t)
+	cookie := loginAsAdmin(t, st)
+	hostID := makeHost(t, st, "empty-backup-host")
+	req, _ := stdhttp.NewRequest(stdhttp.MethodPost, ts.URL+"/api/hosts/"+hostID+"/jobs",
+		bytes.NewReader([]byte(`{"kind":"backup"}`)))
+	req.Header.Set("Content-Type", "application/json")
+	req.AddCookie(cookie)
+	res, err := stdhttp.DefaultClient.Do(req)
+	if err != nil {
+		t.Fatalf("post run-now: %v", err)
+	}
+	defer res.Body.Close()
+	if res.StatusCode != stdhttp.StatusUnprocessableEntity {
+		t.Fatalf("status: got %d, want 422", res.StatusCode)
+	}
+	body := readJSONError(t, res.Body)
+	if body.Code != "backup_paths_required" {
+		t.Fatalf("code: got %q", body.Code)
+	}
+	var jobs int
+	_ = st.DB().QueryRow(`SELECT COUNT(*) FROM jobs WHERE host_id = ?`, hostID).Scan(&jobs)
+	if jobs != 0 {
+		t.Fatalf("invalid backup created %d jobs", jobs)
+	}
+}
+
 func TestRunNowForgetShipsRetentionGroupsAndDryRun(t *testing.T) {
 	t.Parallel()
 	srv, ts, st := rawTestServer(t)