feat(coder): guard session delete against worktree work loss

Deleting a BooChat session CASCADE-wipes its session_worktrees row, which would silently orphan uncommitted/unpushed/unmerged work in the worktree. Add a pre-DELETE gate: the server reads session_worktrees from the shared DB first (no row = chat-only session = delete immediately, zero round-trip), and for worktree-backed sessions calls a new BooCoder endpoint that runs git on the host (only the host systemd service can see /tmp/booworktrees). checkWorktreeWorkAtRisk reports dirty/unpushed/unmerged via the audited hostExec+shellEscape path; default branch is detected from refs/remotes/origin/HEAD (not the worktree's own branch), never hardcoded. Any at-risk worktree returns 409 with per-worktree RiskReport[]; force=true bypasses the check entirely. Fail-closed: coder unreachable/errored also blocks (force still escapes). The sidebar renders a block dialog distinguishing work-at-risk (Commit/Stash/Force) from couldn't-verify (Cancel/Force only); stash uses -u and re-blocks on remaining commits with an explanatory message. Commit never auto-commits — it routes the user to the session.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

apps/web/src/api/client.ts

@@ -151,8 +151,17 @@ export const api = {
         method: 'PATCH',
         body: JSON.stringify(body),
       }),
-    remove: (id: string) =>
-      request<void>(`/api/sessions/${id}`, { method: 'DELETE' }),
+    // force=true bypasses the server-side worktree work-loss guard. A blocked
+    // delete throws ApiError(409) whose body carries { error, reports }.
+    remove: (id: string, force = false) =>
+      request<void>(`/api/sessions/${id}${force ? '?force=true' : ''}`, { method: 'DELETE' }),
+    // Stash the session's worktree (uncommitted changes) on the host, via the
+    // BooCoder proxy. Recoverable escape from the work-at-risk dialog.
+    worktreeStash: (id: string) =>
+      request<{ results: { worktreePath: string; stashed: boolean; error?: string }[] }>(
+        `/api/coder/sessions/${id}/worktree-stash`,
+        { method: 'POST' },
+      ),
     archive: (id: string) =>
       request<void>(`/api/sessions/${id}/archive`, { method: 'POST' }),
     unarchive: (id: string) =>

apps/web/src/api/types.ts

@@ -34,6 +34,19 @@ export interface AvailableProject {
 
 export type SessionStatus = 'open' | 'archived';
 
+// Session-delete work-loss guard. Mirror of WorktreeRiskReport in
+// apps/server/src/types/api.ts — edit both copies together. Arrives as the
+// `reports` field of the 409 body when a delete is blocked.
+export interface WorktreeRiskReport {
+  worktreePath: string;
+  branch: string;
+  dirty: boolean;
+  unpushed: number; // commits ahead of upstream, or -1 if no upstream
+  unmerged: number; // commits not in the project default branch
+  atRisk: boolean;
+  error?: string;
+}
+
 export interface Session {
   id: string;
   project_id: string;

apps/web/src/components/ProjectSidebar.tsx

@@ -19,12 +19,12 @@ import {
   DialogDescription,
 } from '@/components/ui/dialog';
 import { AddProjectModal } from './AddProjectModal';
-import { api } from '@/api/client';
+import { api, ApiError } from '@/api/client';
 import { useSidebar } from '@/hooks/useSidebar';
 import { useSidebarDrawer } from '@/hooks/useSidebarDrawer';
 import { useViewport } from '@/hooks/useViewport';
 import { usePullToRefresh } from '@/hooks/usePullToRefresh';
-import type { SidebarProject } from '@/api/types';
+import type { SidebarProject, WorktreeRiskReport } from '@/api/types';
 import { giteaUrlFor } from '@/lib/projectUrls';
 import { isCoderSessionName } from '@/lib/coder-session';
 import { cn } from '@/lib/utils';
@@ -110,6 +110,16 @@ export function ProjectSidebar() {
   const [renamingProject, setRenamingProject] = useState<string | null>(null);
   const [renameProjectValue, setRenameProjectValue] = useState('');
   const [archiveProjectConfirm, setArchiveProjectConfirm] = useState<{ id: string; name: string } | null>(null);
+  // Work-at-risk dialog: shown when a delete is blocked (409) because the
+  // session's worktree holds uncommitted/unpushed/unmerged work.
+  const [riskState, setRiskState] = useState<{
+    sessionId: string;
+    projectId: string;
+    name: string;
+    message: string;
+    reports: WorktreeRiskReport[];
+  } | null>(null);
+  const [riskBusy, setRiskBusy] = useState(false);
   const navigate = useNavigate();
   const location = useLocation();
   const lastToastedError = useRef<string | null>(null);
@@ -174,16 +184,81 @@ export function ProjectSidebar() {
     }
   }
 
-  async function handleDeleteSession(sessionId: string, projectId: string) {
+  async function handleDeleteSession(
+    sessionId: string,
+    projectId: string,
+    name: string,
+    force = false,
+  ) {
     try {
-      await api.sessions.remove(sessionId);
+      await api.sessions.remove(sessionId, force);
       // Server publishes session_deleted via WS; useUserEvents delivers it.
+      setRiskState(null);
       if (activeSession === sessionId) navigate(`/project/${projectId}`);
     } catch (err) {
+      // 409 => the server's work-loss guard blocked the delete. Open the
+      // work-at-risk dialog with the per-worktree reports instead of toasting.
+      if (
+        err instanceof ApiError &&
+        err.status === 409 &&
+        err.body && typeof err.body === 'object' && 'reports' in err.body
+      ) {
+        const body = err.body as { error?: string; reports?: WorktreeRiskReport[] };
+        setRiskState({
+          sessionId,
+          projectId,
+          name,
+          message: body.error ?? 'This session has work at risk.',
+          reports: body.reports ?? [],
+        });
+        return;
+      }
       toast.error(err instanceof Error ? err.message : 'failed to delete session');
     }
   }
 
+  // Stash the worktree's uncommitted changes (recoverable), then re-attempt the
+  // delete. If unpushed/unmerged commits remain, the retry 409s again and the
+  // dialog re-renders with the narrowed risk.
+  async function handleStashAndRetry() {
+    if (!riskState || riskBusy) return;
+    setRiskBusy(true);
+    try {
+      const { results } = await api.sessions.worktreeStash(riskState.sessionId);
+      const failed = results.find((r) => r.error);
+      if (failed) {
+        toast.error(`stash failed: ${failed.error}`);
+        return;
+      }
+      await handleDeleteSession(riskState.sessionId, riskState.projectId, riskState.name, false);
+    } catch (err) {
+      toast.error(err instanceof Error ? err.message : 'stash failed');
+    } finally {
+      setRiskBusy(false);
+    }
+  }
+
+  // Explicit, destructive override — deletes despite work at risk.
+  async function handleForceDelete() {
+    if (!riskState || riskBusy) return;
+    setRiskBusy(true);
+    try {
+      await handleDeleteSession(riskState.sessionId, riskState.projectId, riskState.name, true);
+    } finally {
+      setRiskBusy(false);
+    }
+  }
+
+  // Route the user to commit it themselves — never auto-commit. Opens the
+  // session workspace where they can use a terminal or agent pane.
+  function handleGoCommit() {
+    if (!riskState) return;
+    const sessionId = riskState.sessionId;
+    setRiskState(null);
+    navigate(`/session/${sessionId}`);
+    toast.info('Open a terminal or agent in this session, commit and push your work, then delete again.');
+  }
+
   async function handleRenameSession(sessionId: string) {
     const trimmed = renameValue.trim();
     setRenamingSession(null);
@@ -216,6 +291,20 @@ export function ProjectSidebar() {
       )
     : 'w-60 shrink-0 border-r bg-sidebar text-sidebar-foreground flex flex-col h-screen';
 
+  // Work-at-risk dialog framing. The server returns 409 in two distinct
+  // situations: (1) work genuinely at risk (reports has ≥1 atRisk entry), or
+  // (2) it couldn't verify (BooCoder down/errored → reports is empty). These
+  // are different user stories — "your work is in danger" vs "the checker is
+  // offline" — so the dialog must not show one generic message for both.
+  const atRiskReports = riskState?.reports.filter((r) => r.atRisk) ?? [];
+  const verifyFailed = riskState !== null && atRiskReports.length === 0;
+  const anyDirty = atRiskReports.some((r) => r.dirty);
+  // Commit-based risk (unpushed/unmerged) that stash can NOT clear. When this is
+  // all that remains (e.g. after a stash cleared the dirty changes), the dialog
+  // explains why it re-blocked and hides the Stash button so it doesn't look
+  // like stash "didn't work".
+  const anyCommits = atRiskReports.some((r) => r.unpushed !== 0 || r.unmerged > 0);
+
   return (
     <aside className={asideCls}>
       <div className="px-4 py-3 border-b flex items-center justify-between">
@@ -499,7 +588,7 @@ export function ProjectSidebar() {
                   const projectId = projects.find((p) =>
                     p.recent_sessions.some((s) => s.id === deleteConfirm.id)
                   )?.id;
-                  if (projectId) void handleDeleteSession(deleteConfirm.id, projectId);
+                  if (projectId) void handleDeleteSession(deleteConfirm.id, projectId, deleteConfirm.name);
                 }
                 setDeleteConfirm(null);
               }}
@@ -509,6 +598,77 @@ export function ProjectSidebar() {
           </div>
         </DialogContent>
       </Dialog>
+
+      <Dialog open={riskState !== null} onOpenChange={(open) => { if (!open && !riskBusy) setRiskState(null); }}>
+        <DialogContent>
+          <DialogHeader>
+            <DialogTitle>
+              {verifyFailed ? 'Could not verify worktree safety' : 'This session has work at risk'}
+            </DialogTitle>
+            <DialogDescription>
+              {verifyFailed ? (
+                <>
+                  {riskState?.message ?? 'The worktree safety check is unavailable.'} Your work may be
+                  fine, but it couldn&apos;t be checked — only force-delete if you&apos;re sure.
+                </>
+              ) : anyDirty && anyCommits ? (
+                <>
+                  Deleting {riskState ? `"${riskState.name}"` : 'this session'} would orphan uncommitted
+                  changes <em>and</em> commits that aren&apos;t pushed or merged. Stash clears the
+                  changes (recoverable), but the commits will still block — push them or force-delete.
+                </>
+              ) : anyDirty ? (
+                <>
+                  Deleting {riskState ? `"${riskState.name}"` : 'this session'} would orphan uncommitted
+                  changes in its worktree. Stash them (recoverable), commit them, or force-delete.
+                </>
+              ) : (
+                <>
+                  Deleting {riskState ? `"${riskState.name}"` : 'this session'} would orphan commits that
+                  aren&apos;t pushed or merged. Stashing won&apos;t recover these — push them, or
+                  force-delete.
+                </>
+              )}
+            </DialogDescription>
+          </DialogHeader>
+          {!verifyFailed && (
+            <div className="flex flex-col gap-2 py-1 text-sm">
+              {atRiskReports.map((r) => (
+                <div key={r.worktreePath} className="rounded border border-border/60 px-3 py-2">
+                  <div className="font-mono text-xs text-muted-foreground truncate" title={r.worktreePath}>
+                    {r.branch || r.worktreePath}
+                  </div>
+                  <ul className="mt-1 list-disc pl-5 text-foreground/90">
+                    {r.error && <li className="text-destructive">git error: {r.error}</li>}
+                    {r.dirty && <li>uncommitted changes</li>}
+                    {r.unpushed === -1 && <li>local-only branch (no upstream)</li>}
+                    {r.unpushed > 0 && <li>{r.unpushed} unpushed commit{r.unpushed === 1 ? '' : 's'}</li>}
+                    {r.unmerged > 0 && <li>{r.unmerged} unmerged commit{r.unmerged === 1 ? '' : 's'}</li>}
+                  </ul>
+                </div>
+              ))}
+            </div>
+          )}
+          <div className="flex flex-wrap gap-2 justify-end pt-2">
+            <Button variant="outline" disabled={riskBusy} onClick={() => setRiskState(null)}>
+              Cancel
+            </Button>
+            {!verifyFailed && (
+              <Button variant="outline" disabled={riskBusy} onClick={handleGoCommit}>
+                Commit&hellip;
+              </Button>
+            )}
+            {!verifyFailed && anyDirty && (
+              <Button variant="outline" disabled={riskBusy} onClick={() => void handleStashAndRetry()}>
+                Stash &amp; delete
+              </Button>
+            )}
+            <Button variant="destructive" disabled={riskBusy} onClick={() => void handleForceDelete()}>
+              Force delete
+            </Button>
+          </div>
+        </DialogContent>
+      </Dialog>
     </aside>
   );
 }