FE-1669: Share Petrinaut snapshots through self-contained URLs by kube · Pull Request #9680 · hashintel/hash

kube · 2026-09-11T14:51:35Z

Summary

Saved nets live in one browser, so their local URLs only work there. This PR adds Share, which builds a link that carries a copy of the whole net, with the current view if wanted.

Recipients open the snapshot read-only at /share and can save an editable local copy. Nothing is uploaded, and later edits to the sender's net do not change the link.

9680.mp4

Links

Changes

Snapshot format

/share#v1.br.<payload> link carries the net

Payload is compact canonical JSON, Brotli quality 11, unpadded base64url.
v1.br. prefix versions the format.
Worker compresses and decompresses

Each worker ends on completion, on cancellation, or after 30 seconds.
Limits of 2 MiB per net and 16,000 characters per fragment

Decoding enforces the size limit while it streams.
A larger net is offered as a YAML download.
Sentry strips the fragment from events, transactions, spans and breadcrumbs

Website

Share icon in a local document's top bar

Opens a dropdown with the link and Copy, Include current view, and Download.
A message appears only when preparing or copying fails.
/share opens the snapshot read-only and saves nothing

Make a local copy saves it at its own /local/<net id> URL with the current view.
Examples and snapshots share one read-only page without Share

Their own URL is the link.

Review fixes

Sharing stays out of the Petrinaut packages

No user-guide page, assistant catalog entry or changeset.
The website README documents snapshot links.
Share is a ghost icon button that opens a dropdown

Test coverage

snapshot.test.ts:

Every core example round-trips; malformed, future, truncated and oversized links fail.
snapshot-client.test.ts:

Worker release, cancellation, a stalled worker stopped after 30 seconds.
-share.test.tsx:

Opening without saving, view changes, Back and Forward, a new fragment, local copy.
share-snapshot-button.test.tsx:

Fixed capture, optional view, file fallback, clipboard failure, cancellation.
strip-snapshot-links.test.ts:

Payloads removed from URLs, breadcrumbs and span attributes; other URLs untouched.
Verified in a browser against the dev server:

Share from a local net, open the link, read-only page offering only Make a local copy.

How to test

Open Petrinaut preview on Vercel
Switch to Simulate > Scenarios
Share
- Copy
Open link in a private window

Expect snapshot in Scenarios view, read-only
Drag a place

Expect read-only notice with Make a local copy
Make a local copy

Expect editable copy at a new /local/<id> URL
Share
- Untick Include current view
  
  Expect link without query parameters

vercel · 2026-09-11T14:51:42Z

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Actions	Updated
hash	Ready	Preview	Oct 9, 2026 8:28pm UTC
petrinaut	Ready	Preview	Oct 9, 2026 8:28pm UTC
petrinaut-docs	Ready	Preview	Oct 9, 2026 8:28pm UTC

1 Skipped Deployment

Project	Deployment	Actions	Updated
hashdotdesign-tokens	Ignored	Preview	Oct 9, 2026 8:28pm UTC

semgrep-code-hashintel · 2026-09-11T14:54:47Z

+): Uint8Array => {
+  if (hash.length > maxSnapshotHashLength) throw new SnapshotError("too-large");
+  if (!hash.startsWith(prefix)) {
+    throw new SnapshotError(/^v\d+\./u.test(hash) ? "unsupported" : "invalid");


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+): Uint8Array => {
+  if (hash.length > maxSnapshotHashLength) throw new SnapshotError("too-large");
+  if (!hash.startsWith(prefix)) {
+    throw new SnapshotError(/^v\d+\./u.test(hash) ? "unsupported" : "invalid");


cursor · 2026-09-11T15:14:50Z

PR Summary

Low Risk
New read-only client route and sharing UI with bounded decode paths; snapshot payloads stay in the URL fragment and are redacted from Sentry, with no backend persistence changes.

Overview
Adds client-side snapshot sharing so local nets can be distributed as self-contained /share#v1.br.<payload> URLs (canonical JSON → Brotli → base64url) with no server upload.

A Share control on editable local documents opens a popover to copy the link (optional current view in query params), download YAML when the net exceeds link size limits, and freeze the net at open time. A new /share route decodes the fragment in a Web Worker (30s timeout, 2 MiB / 16k-char caps), shows a read-only editor via shared ReadonlyDocumentPage (also used by refactored example pages), and Make a local copy persists to /local/<id>. Sentry hooks strip snapshot fragments from breadcrumbs, events, transactions, and spans. Docs and unit/route tests cover codec edge cases, worker lifecycle, UI flows, and telemetry redaction.

^{Reviewed by Cursor Bugbot for commit 2f14564. Bugbot is set up for automated code reviews on this repo. Configure here.}

Copilot

🟡 Changes recommended

Clipboard completion can report a stale URL as copied, and the critical oversized-snapshot download fallback is not exercised.

Once you've addressed the issues Copilot identified, you can request another Copilot review.

Pull request overview

Adds self-contained, read-only Petrinaut snapshot sharing with optional editor-view restoration, local copying, and file fallback.

Changes:

Adds versioned Brotli snapshot encoding through cancellable workers.
Adds sharing UI, /share routing, local-copy behavior, and Sentry redaction.
Adds comprehensive documentation, tests, dependency updates, and changesets.

File summaries

File	Description
`yarn.lock`	Locks the Brotli dependency.
`libs/@hashintel/petrinaut/src/ui/views/Editor/panels/ai-assistant-panel/petrinaut-docs-content.ts`	Registers sharing documentation.
`libs/@hashintel/petrinaut/docs/sharing.md`	Documents snapshot sharing.
`libs/@hashintel/petrinaut/docs/README.md`	Links the sharing guide.
`libs/@hashintel/petrinaut-core/src/ai.ts`	Exposes sharing documentation to AI.
`apps/petrinaut-website/src/sharing/snapshot.ts`	Serializes and validates snapshots.
`apps/petrinaut-website/src/sharing/snapshot.test.ts`	Tests snapshot codec behavior.
`apps/petrinaut-website/src/sharing/snapshot-worker.ts`	Runs Brotli operations in a worker.
`apps/petrinaut-website/src/sharing/snapshot-worker-protocol.ts`	Defines worker messages.
`apps/petrinaut-website/src/sharing/snapshot-codec.ts`	Implements bounded Brotli encoding.
`apps/petrinaut-website/src/sharing/snapshot-client.ts`	Manages worker lifecycle and URLs.
`apps/petrinaut-website/src/sharing/snapshot-client.test.ts`	Tests cancellation and failures.
`apps/petrinaut-website/src/sharing/share-snapshot-button.tsx`	Adds the sharing dialog.
`apps/petrinaut-website/src/sharing/share-snapshot-button.test.tsx`	Tests sharing interactions.
`apps/petrinaut-website/src/sentry/strip-snapshot-links.ts`	Redacts snapshot payloads.
`apps/petrinaut-website/src/sentry/strip-snapshot-links.test.ts`	Tests telemetry redaction.
`apps/petrinaut-website/src/sentry/instrument.ts`	Applies redaction to Sentry hooks.
`apps/petrinaut-website/src/routes/share.tsx`	Adds the snapshot route.
`apps/petrinaut-website/src/routes/-share.test.tsx`	Tests snapshot navigation and copying.
`apps/petrinaut-website/src/main/app/readonly-document-page.tsx`	Extracts shared read-only document UI.
`apps/petrinaut-website/src/main/app/local-storage-demo/local-storage-demo-app.tsx`	Adds sharing to local documents.
`apps/petrinaut-website/src/examples/full-example-page.tsx`	Reuses the read-only document page.
`apps/petrinaut-website/README.md`	Documents snapshot architecture.
`apps/petrinaut-website/package.json`	Adds `brotli-wasm`.
`.changeset/snapshot-sharing-guide.md`	Records the Petrinaut documentation change.
`.changeset/snapshot-sharing-doc-catalog.md`	Records the core catalog change.

Review details

Files reviewed: 25/26 changed files
Comments generated: 2
Review effort level: Balanced

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+  const copy = async () => {
+    if (url === null) return;
+    try {
+      await navigator.clipboard.writeText(url);
+      setCopyState("copied");
+    } catch {
+      setCopyState("failed");
+    }


+  expect(screen.getByRole("button", { name: "Download file" })).toHaveProperty(
+    "disabled",
+    false,
+  );


+  SnapshotResponse,
+} from "./snapshot-worker-protocol";
+
+self.onmessage = async (event: MessageEvent<SnapshotRequest>) => {


cursor

Cursor Bugbot has reviewed your changes and found 1 potential issue.

^{❌ Bugbot Autofix is OFF. To automatically fix reported issues with cloud agents, enable autofix in the Cursor dashboard.}

^{Reviewed by Cursor Bugbot for commit c188a7e. Configure here.}

cursor · 2026-10-09T02:40:21Z

+    let position = 0;
+    for (const chunk of chunks) {
+      output.set(chunk, position);
+      position += chunk.length;


Decompress reuses freed chunk buffers

Medium Severity

decompressSnapshot stores each result.buf and then calls result.free() before the next stream.decompress. Those buffers are only copied into output after the loop, so a later WASM allocation can overwrite earlier chunks. Nets that expand past the 32 KiB output step can open as a corrupted document instead of the shared snapshot.

^{Reviewed by Cursor Bugbot for commit c188a7e. Configure here.}

Share in a local document's top bar builds a /share#v1.br.<payload> link that carries the whole net, Brotli-compressed in a worker, so nothing is uploaded. /share opens the snapshot read-only and saves nothing until Make a local copy. Sentry strips the fragment before sending. Examples and snapshots now share one read-only page and offer no Share button, since their own URL is already the link. The Share dialog is one link row and one options row, with a message only when something fails.

Snapshot links are a demo-website feature, so their guide does not belong in the @hashintel/petrinaut user guide, the assistant's documentation catalog in @hashintel/petrinaut-core, or either package's patch notes. The website README carries what a snapshot holds.

Share is a ghost icon button in the top bar's trailing section, beside version history, and opens a dropdown in place of the dialog: a short hint, the link with an inline Copy, then Include current view and Download on one row. The popover animates in and out, and the button stays pressed while it is open.

kube self-assigned this Sep 11, 2026

github-actions Bot added area/deps Relates to third-party dependencies (area) area/infra Relates to version control, CI, CD or IaC (area) area/libs Relates to first-party libraries/crates/packages (area) type/eng > frontend Owned by the @frontend team area/apps labels Sep 11, 2026

kube added this pull request to stack #9663 September 11, 2026 14:51

semgrep-code-hashintel Bot reviewed Sep 11, 2026

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github-advanced-security Bot found potential problems Sep 11, 2026

View reviewed changes

Comment thread apps/petrinaut-website/src/sharing/snapshot-codec.ts

): Uint8Array => {

if (hash.length > maxSnapshotHashLength) throw new SnapshotError("too-large");

if (!hash.startsWith(prefix)) {

throw new SnapshotError(/^v\d+\./u.test(hash) ? "unsupported" : "invalid");

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kube marked this pull request as ready for review September 11, 2026 15:14

Copilot AI balanced review requested due to automatic review settings September 11, 2026 15:14

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kube force-pushed the codex/fe-1669-snapshot-sharing branch from a47a5f7 to dff1ad1 Compare September 13, 2026 19:07

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github-advanced-security Bot found potential problems Sep 13, 2026

View reviewed changes

Comment thread apps/petrinaut-website/src/sharing/snapshot-worker.ts

SnapshotResponse,

} from "./snapshot-worker-protocol";

self.onmessage = async (event: MessageEvent<SnapshotRequest>) => {

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kube removed this pull request from stack #9663 September 13, 2026 22:49

kube force-pushed the codex/fe-1669-snapshot-sharing branch from dff1ad1 to 65eeb68 Compare September 13, 2026 22:52

kube added this pull request to stack #9700 September 13, 2026 22:54

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kube force-pushed the codex/fe-1669-snapshot-sharing branch from bb2a502 to 05755ea Compare September 15, 2026 20:39

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kube removed this pull request from stack #9732 October 9, 2026 02:33

kube requested a review from a team as a code owner October 9, 2026 02:34

kube force-pushed the codex/fe-1669-snapshot-sharing branch from 05755ea to c188a7e Compare October 9, 2026 02:34

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FE-1669: Share Petrinaut snapshots through self-contained URLs - #9680

FE-1669: Share Petrinaut snapshots through self-contained URLs#9680
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Summary

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Changes

Snapshot format

Website

Review fixes

Test coverage

How to test

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Decompress reuses freed chunk buffers

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