app-privategit-workbench is a browser-based file editor included in the os-privategit host operating system. It presents a local HTTP endpoint that serves a single-page application with a three-column layout: a file tree sidebar, a content viewer, and a plain-text editor.

The workbench is the primary authoring and review surface for Totebox Orchestration operators and Community Members who want direct browser-based access to their archive tree without a terminal session. It is not a publication surface — it writes to the local filesystem and relies on the git-based version-control pipeline for history and promotion.

Architecture

The workbench is a single Rust crate (app-privategit-workbench, Apache 2.0) in the pointsav-monorepo. It has two components:

Write-service (Rust/axum): An HTTP server that handles file reads and writes. It binds to a loopback address and is never exposed directly to external networks. The service enforces root containment (all paths are canonicalized and checked against declared roots), an extension allowlist, and mtime-based conflict detection.

Single-page application: A self-contained HTML file embedded into the binary at compile time via include_str!. The SPA makes API calls through an nginx proxy to the write-service for file reads and writes, and to nginx autoindex routes for directory listings. No external resources are loaded at runtime.

The binary is compiled for the os-privategit host and managed by a systemd unit. The nginx intranet routes /_api/edit/* to the write-service and serves autoindex JSON at /_api/command/, /_api/clones/, and per-sandbox prefixes.

File tree

The sidebar lists the roots declared in config.toml. Each root maps a URL prefix (for example, _clones/project-development) to a filesystem path (for example, /srv/foundry/clones/project-development). Roots may be writable or read-only. The Command workspace root (/srv/foundry) is always read-only; archive roots are writable.

Directory contents are fetched on expand from nginx autoindex JSON. The tree supports nested expansion to arbitrary depth.

Viewer

The centre column renders the selected file according to its extension:

• Markdown (.md): Rendered as HTML using a built-in parser. Fenced code blocks, inline code, headings, lists, links, and tables are supported. Click-to-source from rendered headings and paragraphs moves the editor cursor to the corresponding source line.
• HTML (.html): Displayed in a sandboxed iframe.
• Images: Displayed inline.
• All other types: Displayed as plain text.

The viewer and editor operate independently. Opening a read-only file shows the viewer without the editor panel.

Editor

The right column appears when the open file is in a writable root. The editor is a <textarea> with the following features:

• Line number gutter with active-line highlight
• Cursor position indicator (line and column) in the editor bar
• Dirty state indicator (orange dot) when unsaved changes are present
• Save: Cmd+S or the Save button — writes via PUT /file with the current mtime to detect concurrent edits; shows a conflict dialog on HTTP 409
• Find / Replace bar (Cmd+F): incremental match highlighting, previous / next navigation, Replace and Replace All; preserves native undo stack via execCommand
• Document Outline panel (Cmd+Shift+O): lists all markdown headings (H1–H6) or TOML table headers from the current file; filter by typing; click or press Enter to jump the cursor to that symbol
• Toggle line comment button: extension-aware (// for Rust/JS/TS, # for TOML/YAML/shell); toggles selected lines
• Go to line (Ctrl+G)
• Tab inserts two spaces
• Bracket auto-close for {, [, (
• Line move up / down (Alt+↑ / Alt+↓)
• Line duplicate (Shift+Alt+↓)

Security model

The write-service enforces four layers of containment:

Root containment: Every path is canonicalized with std::fs::canonicalize and verified to remain within the declared root's filesystem path. Paths that resolve outside the root are rejected with HTTP 400.

CSRF guard: Every PUT /file request requires the X-Foundry-Editor: 1 header. The browser's cross-origin policy prevents third-party pages from adding this header.

Extension allowlist: Writes are permitted only for recognized plain-text and source-code extensions. Binary formats and unknown extensions are read-only through the workbench.

Writable flag: The writable = false declaration in a root entry causes all write attempts to that root to be rejected with HTTP 403, regardless of filesystem permissions.

The systemd unit runs with ProtectSystem=strict and ReadWritePaths= scoped to the declared writable roots. Adding a new writable root requires updating both config.toml and the systemd service file; missing the service file update causes silent write failures at the filesystem layer.

Relationship to os-privategit

app-privategit-workbench is included in the os-privategit host operating system alongside app-privategit-design-system and service-privategit. It is the authoring surface for operators who use the privategit tier — a locally-hosted, network-isolated development environment for Totebox Orchestration instances.

The crate is licensed under the Apache License, Version 2.0 and intended for downstream deployment in customer-tier instances of os-privategit. An operational setup guide is available in the customer fleet deployment catalog.

Planned additions

• Phase 4 (planned/intended): CodeMirror 6 integration for syntax highlighting; authenticated roots with per-user writable scope.