cg-media-viewer

A DeepSeek Harness plugin that plays video and audio inside the right sidebar, including the file tree of dsh-better-sidebar.

• Español

The problem it solves

The right sidebar has two different preview paths, and each one keeps its own viewer registry:

Where you open the file	Who renders it	Video/audio
Built-in Files tab	ctx.documentPreviews (video / audio renderers)	works while dsh-media-web-preview is active
dsh-better-sidebar file tree	its own ctx.betterSidebar registry	fell through to binary-download: "no preview, download"

dsh-better-sidebar never consults documentPreviews (zero references in its bundle), so turning dsh-media-web-preview on or off changes nothing in its tree. What was missing were viewers registered in its registry.

What it does

Registers two file viewers in ctx.betterSidebar:

Viewer	Extensions
cg-media:video	mp4 m4v webm ogv mov mkv avi mpg mpeg 3gp 3g2 m2ts
cg-media:audio	mp3 m4a m4b aac wav flac ogg oga opus weba

• Native browser player (<video> / <audio>) with controls, seek, volume and fullscreen.
• Real seek when the bytes come from a route that honours Range: the viewer asks GET /api/media?path=<absolute path> (the Host half of dsh-media-web-preview), which answers 206 Partial Content with Content-Range. Seeking does not download the whole file.
• Honest fallback with no ranges. When the only available source is the mediaUrl that the dsh-better-sidebar host already computes (/sidebar/file, whole file, no ranges), the viewer says so: the footer shows "No seek: the server does not support byte ranges, so the whole file is downloaded", the element starts with preload="none", and Download becomes the primary action. It does not pretend the two modes are equivalent.
• Errors told apart. MediaError.code 2 (network) and 3 (decode) show a network notice with a Retry button; code 4 (format not supported) shows the format notice; code 1 (aborted, i.e. the page or the user cancelled the load) is not treated as a failure.
• Footer with the tab title, the size when the host reports it, Download and Open in new tab.
• When the harness exposes its locale service, the UI follows the active language (English and Spanish dictionaries); otherwise it stays in English.

mkv and avi are claimed because the file still deserves a player, but Chromium usually cannot decode them: there the viewer shows the format notice and leaves the download. That call belongs to the browser, not to the plugin.

Deliberately not claimed:

• ts: in a coding harness a .ts file is almost always TypeScript. Claiming it as MPEG-TS video would replace the code view with a broken player.
• aiff, aif, wma, mid, midi: Chromium does not decode them, so claiming them only swaps a download panel that works for a notice that does not.

Requirements

• DeepSeek Harness >=0.2.1-rc.2 <0.3.0-0.
• dsh-better-sidebar >=0.28.0. Third-party and an optional peer dependency: without it this bundle still loads and simply stays inert (there is no registry to register into), and nothing in the harness breaks.
• For ranged seeking, a route that answers Range on api/media: that is dsh-media-web-preview, the Host half that owns /api/media. Without it, playback still works through the host mediaUrl, without seek.

Install

From npm:

npm install cg-media-viewer

Then, inside DSH:

plugin_manager action=install_bundle target=cg-media-viewer

Refresh the page once so the client bundle enters the module graph. To remove it:

plugin_manager action=remove_bundle target=cg-media-viewer

From a repository checkout (development):

git clone https://github.com/DonGeeo87/cg-media-viewer.git

plugin_manager action=install_bundle target=<path to the cg-media-viewer directory>

With a link: install, editing lib/client.js is enough for the next load; if the browser already had the old module, restart DSH.

How to tell it is alive

• Settings > Side: the viewer inventory lists Video and Audio with the play triangle and their switches.
• Open an MP4 from the sidebar tree: the panel shows a <video> with controls instead of the download button.
• The root node of the player carries data-cg-media="video" (or "audio").

Verification

node --check lib/client.js
node --check lib/index.js
node --test

The suite (test/client.test.mjs) loads the real lib/client.js with a fake window loader and a minimal React, and checks: both viewers register with fetchStrategy: 'mediaUrl' and priority 100; the claimed extension lists contain no ts, aiff, aif, wma, mid or midi; one effect registers both viewers and returns both disposers; a viewer id already taken does not prevent the other from registering; the no-range footer notice, preload="none" and primary download; the MediaError classification with Retry; the two-step fallback from /api/media to mediaUrl; the tab title coming from props.title; and the locale path (dictionaries registered, active language used, English fallback when the service throws).

Known limits

• The Host half registers no routes: it reuses /api/media. If dsh-media-web-preview is removed, everything keeps working through the fallback, without seek.
• The size is shown only when the host reports it. With fetchStrategy: 'mediaUrl' the host does not measure the file, so the footer normally shows just the title (no extra HEAD request per open).
• No subtitle tracks, playlists or playback rate: it is the browser's player.
• A missing file that also fails on the host route is reported by Chromium as MEDIA_ERR_SRC_NOT_SUPPORTED (code 4), so it surfaces as the format notice; Retry is still offered for transient cases.

Where it lives

Where	Identifier
npm	cg-media-viewer
GitHub	https://github.com/DonGeeo87/cg-media-viewer (MIT)

License

MIT.

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Español

Plugin de DeepSeek Harness que reproduce video y audio dentro del sidebar derecho, también desde el árbol de archivos de dsh-better-sidebar.

El sidebar derecho tiene dos caminos de vista previa y cada uno lleva su propio registro de viewers. La pestaña Files de fábrica usa ctx.documentPreviews (los renderers video / audio de dsh-media-web-preview), pero el árbol de dsh-better-sidebar usa su propio registro y no consulta ese servicio: por eso un MP4 abierto desde ahí caía en su panel de descarga. Este bundle registra cg-media:video y cg-media:audio en ctx.betterSidebar y llena ese hueco.

• Reproductor nativo del navegador, con controles, seek, volumen y pantalla completa.
• Seek real cuando los bytes vienen de una ruta que respeta Range (GET /api/media?path=<ruta absoluta>, la mitad Host de dsh-media-web-preview, que responde 206 Partial Content).
• Respaldo honesto: si el único origen disponible es el mediaUrl del host (/sidebar/file, archivo completo, sin rangos), el pie lo dice, el elemento arranca con preload="none" y Descargar pasa a ser la acción principal. No se presenta como equivalente.
• Errores diferenciados: MediaError.code 2 (red) y 3 (decodificación) muestran el aviso de red con Reintentar; el código 4 (formato no soportado) muestra el aviso de formato; el código 1 (abortado) no se trata como falla.
• El pie muestra el título de la pestaña, el tamaño cuando el host lo informa, Descargar y Abrir en pestaña nueva.
• Si el harness expone su servicio locale, la interfaz sigue el idioma activo (diccionarios en inglés y español); si no, queda en inglés.

A propósito no reclama ts (en un harness de código un .ts es TypeScript), ni aiff, aif, wma, mid ni midi (Chromium no los decodifica: reclamarlos cambia un panel de descarga que funciona por un aviso que no).

Requisitos: DeepSeek Harness >=0.2.1-rc.2 <0.3.0-0; dsh-better-sidebar >=0.28.0 como peer opcional (sin él el bundle queda inerte y nada se rompe); y dsh-media-web-preview si se quiere seek por rangos.

Instalar: npm install cg-media-viewer y después plugin_manager action=install_bundle target=cg-media-viewer; refresca la página una vez. Desde un clon del repositorio se instala igual apuntando target a la carpeta. Se quita con plugin_manager action=remove_bundle target=cg-media-viewer.

Verificar: node --check lib/client.js, node --check lib/index.js y node --test (19 pruebas).

Límites: el tamaño aparece solo si el host lo informa (con fetchStrategy: 'mediaUrl' no lo mide); sin dsh-media-web-preview todo funciona por el respaldo, sin seek; no hay subtítulos, listas de reproducción ni velocidad, es el reproductor del navegador.

Licencia MIT.