viewer.feed

Module nuspace.system.devices.web.viewer.feed.

The viewer feed: one arm per interaction, all in parallel. Host only.

• browser to store. A viewer event runs one op over its own fields.
• store to browser. An open plane or its pane's run changed; its arm ships the plane or the statuses again, keyed by plane_id.

A pane with nothing to draw is told why. A route nav does not bring up (routable) ships set_absent in place of the plane: missing when there is no such plane, headless when it is not a ui one. The same arm reships, so a plane deleted from another tab turns its pane absent, and one that comes back or turns ui is drawn again.

Which planes are open is connections[sid].routes, written by the device's route arm (D15), never read off the browser. One arm per plane in it: its subscriptions die with it when the plane leaves routes.

Narrow watch. A plane is shipped again when anything under its row changes, its version counting every write to its cells included; the statuses when the pane's plane run or the plane's cells change, or a cell run of the pane's run starts, begins or ends. Nothing of another plane or run wakes either, and neither does a cell writing its state or a cell run writing its output. Both are level: each ship reads the store as it is, so a change a fresh subscription missed ships on the next re-check, and only what reads otherwise than it last shipped is sent.

Meta goes both ways. A shipped plane carries its whole meta, and a plane.meta event merges keys into it. A plane's props never reach the browser, a cell's ship as a flat made_by and has_ui, and neither is written from it.

Statuses come from records, never stored. A pane shows the plane run nav made for it (pane_run), so two tabs on one plane each see their own. Per cell: its live cell run in that run if it has one, else its most recent. Live and not started is starting, live and started is running. Ended, it is idle when it exited ok, stopped when interrupted or killed, failed (with its error) when failed. No run, or no cell run of the cell, is idle.

viewer_feed

The viewer, live, as one term. Built per connection, never ends.

web.viewer_feed(viewer, sid, snippets=())

Path nuspace.system.devices.web.viewer_feed. Defined on nuspace.system.devices.web.viewer.feed, bound as a function. Builds nu.Nu.

Arguments

Undocumented: example.