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ConsoleMonster

Recording and replay

Record a live session as JSON lines, replay it into the same dashboard, and export widgets, frames and recordings to HTML, SVG, text and asciicast.

A live session can write every applied event to a JSON-lines file: LiveSessionOptions.RecordPath or RecordWriter in C#, Start-ConsoleDashboard -RecordPath in PowerShell. A recording holds updates, not pictures, so it is played back into the widget tree it was recorded with.

{"consolemonster":"recording","version":1}
{"t":1,"target":"dashboard","op":"status","text":"discovering forest","state":"running"}
{"t":1,"target":"phases","op":"state","key":"Discover","state":"running"}

These are the first lines of the recording behind the live dashboards page, which you can download. LiveRecorder writes the format and LiveRecordingReader reads it, with no dependencies.

Replay

using (StreamReader reader = File.OpenText("run.jsonl")) {
    LiveSession.Replay(dashboard, reader, new LiveSessionOptions(), speed: 1.5);
}

Start-ConsoleReplay does the same in PowerShell. The replayed clock follows the recorded timeline, so header clocks and spinners move as they did.

Export

Any widget, rendered frame or live-session snapshot can be saved as a self-contained file:

string html = ConsoleExporter.ToHtml(widget, new ExportOptions { Width = 120, Title = "Nightly run", WindowChrome = true });
string svg = ConsoleExporter.ToSvg(session);
string text = ConsoleExporter.ToText(frame);
string player = Recording.ExportHtml(dashboard, File.OpenText("run.jsonl"));

Get-Service | Select-Object -First 8 Name, Status, StartType | Format-ConsoleTable -AsWidget | Export-ConsoleFrame -Path .\services.html
Export-ConsoleRecording -Dashboard $dashboard -Path .\run.jsonl -Destination .\run.svg
  • HTML pages carry a dark and a light rendering and show the one the viewer prefers. Glyphs a fallback font could draw at another width are boxed to their cell, and block elements and braille are painted as cell backgrounds.
  • SVG draws box drawing, block and braille characters as shapes; other glyphs stay selectable text.
  • Recordings export to an HTML player with scrubbing, an animated SVG using CSS keyframes only, or asciicast v3.
  • Links become links for http, https, mailto and ftp only, and nothing is fetched from the network.

This site renders widgets through ConsoleMonster and uses its recording exporter and player for event replays. The site tool also converts captured VT streams and shares cell styles across the gallery. The site tool's notes describe how.

Targets

Every write, live session, prompt and status helper goes to an ITerminalTarget: a profile, a theme, a writer and an input source. ConsoleTarget.Instance is the process console; TestTerminal.Target(...) returns a RecordingTarget for tests, WriterTarget writes append-only lines to a TextWriter, and NullTarget.Instance discards output. using (Terminal.Use(target)) { ... } sends everything in the block to a target, and the scope flows with async calls. In PowerShell, Use-ConsoleTarget runs a script block with ConsoleMonster output going to a file (-Path), a writer or a target, or returned as a string.

Testing output

The helpers ConsoleMonster's own tests use are public: TestTerminal.RenderText(widget, width: 80, glyphs: GlyphTier.Ascii) renders at a fixed size, tier and culture, GoldenFile.Match compares with a golden file and shows the first differing line, and ScreenCapture with scripted keys captures prompts, menus and forms. In Pester, Assert-ConsoleOutput -GoldenPath does the same.

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