Merge pull request #2052 from StrajnarFilip/claude/lan-share-read-only

M9: share a file on the local network read-only, with a view-only code

docs/collab-protocol.md

@@ -597,8 +597,16 @@ resuming with its offline edits, and leaving the session going back to snapshot
   `local`), so a local share is protected by 44 bits, not 128: a code is guessed over the network
   at the rate the host accepts connections, which makes 44 bits years of trying, but treat it as
   a secret for the local network, not for the internet. The invite link names the same session.
-  Whoever sees the code learns the host's address. Everyone who joins edits; a host without an
-  IPv4 address gets no code and shares its link.
+  Whoever sees the code learns the host's address. The session has two secrets, so two codes:
+  the **edit code** and a **view-only code** (the same address and port, a 44-bit secret of its
+  own). The host welcomes whoever joins with the view secret as a viewer (`Access::View`): they
+  see every change and everyone's presence, the app makes the file read-only for them, and the
+  session refuses any batch they send anyway, as a server does for its view links. The Share
+  popover picks which code shows (Can edit / Can view, also before sharing starts, so the edit
+  code need never be on screen; `collab.share {access}`, whose `link` and `url` are the ones that
+  go with the code shown, so a view-only share never hands out the edit secret); picking one later changes
+  nothing for who already joined. There is no comment code on the local network. A host without an IPv4
+  address gets no codes and shares its links.
 - **In the browser** a code joins like a link (the page asks the server over its own WebSocket,
   then opens the session's); it shares online through the server in Preferences as the desktop
   app does, and not on the local network (a page can't listen).

docs/collaboration-parity.md

@@ -1,6 +1,6 @@
 # Collaboration parity
 
-> **Last reviewed:** 2026-10-10 · **Last updated:** 2026-10-31 · **Change:** minor (a live session's welcome sends the document compressed to clients that read it, about seven times smaller (#1665); a server can list the files shared from it now for everyone who reaches it, Home ▸ Online shows them and their links carry no secret (`team_files`, part of #742); `figcraft-server` checks the server key by comparing SHA-256 digests, not the raw keys (#1130); joining and leaving a file nobody is editing reads and writes nothing on the server: it stays loaded a minute after everyone leaves (#1074); `comment.people` lists names that were only @mentioned, and `comment.next` and `comment.prompt` carry the mentions too (#1415); share links can comment: a third access level beside edit and view, whose holder sees the file live and adds, replies to, reacts to and resolves comments but can't change the design; `comment.list {mentions}` lists only the threads that @mention a name (#1415); the browser build publishes files to a server, so Share ▸ Online and Publish to server work there (#917); an AI agent attached over MCP shows where it works (#1416); one name for live sessions and comments: Preferences ▸ Your name, in the Join dialog too, kept in the browser, and a rename shows at once in the sessions you are in (#1380); the Join dialog shows a join from the click until its file is ready, with Cancel, and a failed join with Try again (#1381); requests that change a server's files have a budget per address, the server key's too, and join codes are found by their hash (#1075); comment.list reports each message's @mentions (#1415); the batches kept for reconnecting apps are bounded in bytes by default, and `figcraft-server` takes `max_log_mb` (#1069); sibling placement in live sessions searches instead of counting (#1065); an AI agent attached over MCP comments under its own name, with an Agent label (#1414); a refused batch's fixes take time linear in the batch (#1063); image entries are checked as they apply; branches in live sessions and branch history entries; server message limits follow `max_file_mb`; a damaged log generation field keeps flushed edits; the web build joins from a `#join=` link; removing someone from a live session; live-session revert guard; live sessions per document; a public figcraft-server: open hosting, owner tokens, per-address limits, idle expiry, moderation, install.sh; cursor chat and spotlight in live sessions; branch version history and finer list merges; comments and version history behaviour suite and fixes; hosting the server: `wss://` in the desktop app, server releases, deployment guide; team libraries on the server and swap library; branches: create, update from main, review and merge; wording: the standalone server with share links to edit or view; numbers unchanged) · **Target:** Figma Design (desktop app 126.10.7)
+> **Last reviewed:** 2026-10-10 · **Last updated:** 2026-11-06 · **Change:** minor (a file shared on the local network can be shared to look at only: a view-only code next to the edit code, picked in the Share popover before or while sharing)
 
 Figma is multiplayer first; FigCraft is local first. **Ready ~13% (estimated):** comments, version
 history and branches (review and merge) work inside one file; the real-time collaboration core landed in #103 (sync model,
@@ -15,7 +15,7 @@ cursors, selections, text carets, cursor chat and spotlights shown live ([`colla
 | Real-time co-editing | yes | **core built, no networking** (#103): client-scoped ids, per-property change sets with fractional positions, server ordering and validation, optimistic clients, binary messages; randomized multi-client convergence tests over real commands. Live sessions over the network landed (`crates/collab-net`): the WebSocket transport (keep-alive, size and rate limits, reconnect with backoff), hosting from the app (this machine or the local network) with invite links, live cursors with name tags, selections, avatars and follow, `collab.*` commands. Document sync between apps works over them (the host's server orders every batch; guests open the host's file as a new tab). Sessions are per document: each open file has its own or none, several run at once (host one, join another, publish a third) and keep syncing behind the tab in front, and closing a file ends its session only. Revert to saved is refused until the document leaves its live session; its access checks and sync association stay intact. Undo is per person (only your own steps, others' later writes left alone), refused edits roll back with a toast, and a reconnect resumes as the same client with what it missed (or a snapshot) and sends what was made offline. The browser build joins (same messages through the browser's WebSocket API); `figcraft://` invite links open the desktop app and join. Styles, variables, collections, modes and comments made in a session take ids from their creator's space (the server checks it), so concurrent creations all survive; modes, per-mode values and replies inside one entry still resolve last-writer-wins. A standalone `figcraft-server` keeps many files, persists them (a snapshot plus a log, compacted), loses nothing confirmed across a restart (apps resume as the same participants) and takes files published from the app (File ▸ Publish to server…). The desktop app and the CLI open `wss://` links too (TLS through a reverse proxy), and releases ship the server for Linux with a deployment guide (systemd, Caddy, nginx, Docker) and `install.sh`. A server can be open to the public: anyone publishes without the key, within limits per address, and files nobody opens expire. Message limits follow the server's `max_file_mb`, so files above 64 MiB publish and open (the client takes at most 1 GiB from a server, and the server warns when large limits meet open publishing, #705); a damaged generation field in a file's log no longer drops the edits flushed to it (#687). Image entries are checked as they apply: a key must be a plain name (letters, digits, `-`, `_`; it becomes `images/<key>` in a saved file), bytes under a content-hash key must hash to it (lowercase sha256), a side is at most 65 535 px and the decoded bytes at most 256 MiB (what the importers read), a key's bytes can't be replaced and an image a layer shows can't be removed, so no collaborator can poison the shared image store or balloon memory; snapshots and server logs from before these checks open without the images they refuse (#1086). The batches kept for apps that reconnect are bounded in bytes by default (64 MiB; `max_log_mb` on `figcraft-server`), and an app further behind catches up with a snapshot (#1069). Placing a layer among its siblings is a binary search, so large pastes and reorders in one batch no longer take quadratic time (#1065). A refused batch's fixes take time linear in the batch: each deleted layer is restored once and each entry fix looked up once (#1063). Left: server archives beyond Linux | 25–55 |
 | Live cursors, selections, viewports; follow / observation mode; spotlight | yes | **done, in live sessions**: named cursors (one name for live sessions and comments: Preferences ▸ Your name, also in the Share popover and the Join dialog, kept in the browser too; a rename shows at once in the sessions you're in, #1380), selection outlines, avatars (an AI agent attached over MCP also shows its avatar and an outline around the layers it last edited or selected while it works, in or out of a session, #1416), follow (click an avatar), others' text carets and selected characters with their names, a note when two people type in one layer; spotlight (your avatar's menu, `collab.spotlight`): everyone follows your view and page, people who join later too, anyone who moves their view stops following and a banner offers to follow again, a newer spotlight takes over. Left: polish (no accounts, so anyone in the session can spotlight) | 2–4 |
 | Cursor chat, audio, high-fives | yes | **partial, in live sessions**: cursor chat (`/` opens a bubble at your pointer; everyone sees it as you type, it fades a few seconds after the last change, Enter sends and Escape takes it back, 100 characters; `collab.cursorChat` for agents); sent as ephemeral presence the host checks and rate-limits, never stored. No audio, high-fives or emote reactions | 2–5 |
-| Share links, permissions (view / edit), teams and projects | yes | **partial**: sharing with a join code from the Share popover (online: the file goes to the server in Preferences and the server names its edit, comment and view links with short codes; local network: the app hosts and the code carries its address; one field joins with a code or a link, in the popover and on the home screen, and the Join dialog then shows the join until its file is ready (Cancel), or why it failed (Try again, #1381); the browser build also joins from a link in its URL's fragment, `#join=…`, which never reaches the web host's logs, capped at 6 KiB and checked like a `figcraft://` link (#712; unit-tested, not run in a browser), and shares online and publishes to a server as the desktop app does, though not on the local network (#917; the owner token of a file it puts on an open server lasts as long as the page)); `figcraft-server` share links per file with edit, comment or view access (a viewer sees changes and presence, a "View only" badge and only the moving tools; a commenter also adds, replies to, reacts to and resolves comment threads, with a "Can comment" badge and the comment tool, #1525; the server refuses their other edits), revocable at once, tokens stored as hashes; managed from the app's Share popover (first links), the server's command line or a managing connection. On a server open to the public, whoever published a file manages it with its owner token (links, name, removal: `collab.manageFile`), which the app remembers: Home ▸ Online lists your online files (open again as owner, start and stop sharing, copy the code, rename, remove, forget), with one request per server for what became of them; anyone in a file can report it, and the operator blocks addresses. The person hosting a session, or a file's owner, removes someone from it (right-click their avatar, `collab.removePerson`): they are disconnected and their address can't join that file again while it runs. The list is per computer; a server only a team reaches can also list the files shared from it now for everyone (`team_files`): Home ▸ Online shows that team list for the server in Preferences, a row joins its file, and its links (`figcraft://join?server=…&file=…&team=1`, or the browser build's) carry no secret and stop working with the share. No accounts, teams or projects | 8–17 |
+| Share links, permissions (view / edit), teams and projects | yes | **partial**: sharing with a join code from the Share popover (online: the file goes to the server in Preferences and the server names its edit, comment and view links with short codes; local network: the app hosts and the code carries its address, with an edit code and a view-only code, picked before or while sharing, whose holders see every change and can't make one; one field joins with a code or a link, in the popover and on the home screen, and the Join dialog then shows the join until its file is ready (Cancel), or why it failed (Try again, #1381); the browser build also joins from a link in its URL's fragment, `#join=…`, which never reaches the web host's logs, capped at 6 KiB and checked like a `figcraft://` link (#712; unit-tested, not run in a browser), and shares online and publishes to a server as the desktop app does, though not on the local network (#917; the owner token of a file it puts on an open server lasts as long as the page)); `figcraft-server` share links per file with edit, comment or view access (a viewer sees changes and presence, a "View only" badge and only the moving tools; a commenter also adds, replies to, reacts to and resolves comment threads, with a "Can comment" badge and the comment tool, #1525; the server refuses their other edits), revocable at once, tokens stored as hashes; managed from the app's Share popover (first links), the server's command line or a managing connection. On a server open to the public, whoever published a file manages it with its owner token (links, name, removal: `collab.manageFile`), which the app remembers: Home ▸ Online lists your online files (open again as owner, start and stop sharing, copy the code, rename, remove, forget), with one request per server for what became of them; anyone in a file can report it, and the operator blocks addresses. The person hosting a session, or a file's owner, removes someone from it (right-click their avatar, `collab.removePerson`): they are disconnected and their address can't join that file again while it runs. The list is per computer; a server only a team reaches can also list the files shared from it now for everyone (`team_files`): Home ▸ Online shows that team list for the server in Preferences, a row joins its file, and its links (`figcraft://join?server=…&file=…&team=1`, or the browser build's) carry no secret and stop working with the share. No accounts, teams or projects | 8–17 |
 | Comments: pins on frames and layers, threads, reactions, @mentions, resolve, unread, search and filters, links, in the presenter | yes (shared) | **done, local**: stored in the file, your name from Preferences (an AI agent attached over MCP comments as its own name, marked Agent); a behaviour suite from the documentation (pinning and following layers, threads, own edits and deletes, mentions, reactions, C and Shift+C, stepping, filters, saving, copy and paste); restoring a version keeps them. `comment.list` (CLI, MCP) gives each message its `mentions` (`{name, known, you}`, by the highlighting rule). In a live session threads sync and anyone in it can reply, react and resolve (no accounts: a name is who you are) | (shared once multiplayer lands) |
 | Version history: named versions, autosave checkpoints, view before restore, restore, duplicate | yes (cloud) | **done**, saved in the `.figcraft` file: restoring keeps the replaced design as an autosave first, a titled autosave becomes a named version, merging a branch records the file before and after. Versions are per person in a live session (a shared history needs accounts); no comparing two versions (Dev Mode compares a ready-for-dev layer with its state when marked) | — |
 | Branching and merging | yes (paid plans) | **done, also in live sessions**: branches saved in the `.figcraft` file, each opened in its own tab; Review and merge shows both sides' changes since the branch was made and the conflicts (the same property on both sides, or a layer deleted on one side and edited on the other), each resolved for the branch or main; merge as one undo step (the branch is archived, the main file's history gets a version for the merge), update from main, archive. Each branch keeps its own version history (saved, viewed and restored on the branch tab, kept when it is merged or archived; entries for its creation and updates from main); fills, strokes, effects, layout grids, export settings, guides, interactions, annotations and Dev Mode resources merge item by item. In a live session a branch stays with its author (its ids in their own client space, far above the main file's) and merging it is one edit everyone gets; peers' edits merge against the branch's own base and conflicts resolve as offline; a view link refuses merging. Left: others in the session can't see or open your branches (the server would have to keep them); text runs conflict as a whole; a branch made offline that adds layers merges only outside a session | 1–2 |
@@ -26,6 +26,7 @@ cursors, selections, text carets, cursor chat and spotlights shown live ([`colla
 
 | Date | Change | Summary |
 |---|---|---|
+| 2026-11-06 | minor | M9: a file shared on the local network can be shared read-only. The session the app hosts has a second secret, so a view-only code next to the edit code (same address and port, a 44-bit secret of its own); whoever joins with it is welcomed as a viewer, sees every change and presence, gets the "View only" badge and only the moving tools, and the session refuses their edits. The Share popover offers Can edit / Can view under Local network before sharing starts (the edit code then never shows) and while sharing; `collab.share {via: "local", access: "view"}` does the same (its `link` and `url`, like its `code`, are the view-only way in), and `share` in `collab.peers` lists both codes and links. No comment code on the local network. Numbers unchanged. |
 | 2026-10-31 | patch | M9, #1665: the document in a live session's welcome goes compressed (deflate) to clients whose hello announces `packed`, about seven times smaller on the wire (a synthetic file of 4,040 layers: 397 KB to 53 KB); older clients keep getting it uncompressed, and the client reads a packed document only up to the size an uncompressed welcome could have had. |
 | 2026-10-30 | minor | M9, part of #742: a team list on `figcraft-server`. With `team_files = "edit"` (or `comment`, `view`) everyone who reaches the server sees the files shared from it now (a link of theirs has a join code: Share ▸ Start sharing) and joins them by a team list link, `figcraft://join?server=…&file=…&team=1`, which carries no secret: the server hands out the file's team link while it stays shared (`ResolveTeam`, answered like a join code), and Stop sharing revokes it with the others, disconnecting whoever joined with it. Turning the list off or changing its access refuses the old team links at once. `collab.files {refresh}` asks the server in Preferences for its list (`Admin::Team`; not the public server FigCraft ships with), and Home ▸ Online shows it below your own files: a row joins its file, its menu copies the link for the app or, with the server's `web_url`, for the browser build (`<web_url>#join=…`). A browser build served beside its server names it with `<meta name="figcraft-server">`, the page's default for sharing, codes and the team list. No accounts: the list is for a server only your team reaches. Tests: `team_tests` (the server and apps over loopback), `code_tests` (links and the browser's driver), `online_tests` (the Online section), `query_tests` (the page's server). Percentages and hours unchanged |
 | 2026-10-30 | minor | M9, #1130: `figcraft-server` compares the SHA-256 digests of the presented and the kept server key instead of the raw strings, as `docs/server.md` says; the key file, `figcraft-server key` and rotation are unchanged. Numbers unchanged. |