PVServ

A local server for viewing plotly plots

TODO

Image support (matplotlib, etc.)

Goal: support images the way foundry-nvim's plot server does (an image plus a mime type), alongside plotly figures.

Core change

• The plot table needs a mime column that defaults to the plotly type, so existing rows keep working.
• Existing databases need an ALTER TABLE, because CREATE TABLE IF NOT EXISTS won't add the column.
• Store image bytes as a BLOB. Decode base64 on ingest, since base64 costs about 33% more space.

Ingest

• POST /plotviewer/plot already takes a raw body. The least disruptive change is to branch on Content-Type.
• application/json or no type keeps today's behavior. image/* is stored as an image.

Rendering

• Plotly rows embed the whole figure JSON in data-plot-json and render client-side. Embedding base64 images the same way would be much heavier, especially in SSE payloads.
• Serve image bytes from a URL like /plot/<id>/image and use a plain <img src>. The browser caches them.
• plot.html and plot_list_item.html both need a branch on mime.
• renderPlot and renderThumbnails in plot.js already skip elements with no data-plot-json, so they need little or no change.
• The sidebar thumbnail for an image is just the <img>. Plotly thumbnails are rendered to PNG client-side.

events.js

• The htmx:afterSwap handler on #recent-plots reads data-plot-json from the new first sidebar item. It then hand-builds the #plot-container HTML around that JSON and calls renderPlot().
• An image item has no data-plot-json, so the handler hits if (!preview) return;. The image would appear in the sidebar but never in the main pane.
• Fix: add an image branch there, or have it trigger the sidebar item's existing hx-get so the server renders the right partial for each type. The second option avoids duplicating markup in JS.
• The click, resize and SSE connection-indicator handlers don't need to change.

Things that look different for images

• No theme, so no paper_bgcolor or font colors to read. The sidebar item and plot area need a neutral default.
• No layout.title, so #title-text is empty unless a title is sent.
• Transparent matplotlib PNGs will look odd on the dark background.