Andy Gayton cablehead

Based on my analysis of the codebase, here's the updated spec for adding .cat -T <topic> / .cat --topic <topic> functionality:

Code Flow Analysis

The .cat command flows through these layers:

xs.nu wrapper → calls xs cat CLI with flags
src/main.rs CommandCat → parses CLI args, builds ReadOptions
client/commands.rs cat() → makes HTTP GET to / with query params
api.rs handle_stream_cat() → parses query into ReadOptions, calls Store::read
store/mod.rs Store::read() → performs backlog scan + live subscription

Change command event output: Instead of streaming each output Value as a .recv event, collect the full pipeline, then append a single frame with topic <name>.response.
Apply return_options: The new .response event must respect the suffix and ttl from the command's return_options.
Remove .complete event: No .complete frame is emitted for these commands.

meta: note that Nushell requires ( .. ) around multi-line commands, and it doesn't support trailing slashes for line continuation

# Get clean task definition template (remove AWS-managed fields)
(aws ecs describe-task-definition --task-definition your-task-definition

	event: datastar-patch-elements
	data: elements <section id="todomvc" data-on-load="@get('/examples/todomvc/updates')"><header id="todo-header"><input type="checkbox" data-on-click__prevent="@post('/examples/todomvc/-1/toggle')" data-on-load="el.checked = false"> <input id="new-todo" type="text" placeholder="What needs to be done?" data-signals-input data-bind-input data-on-keydown="
	data: elements evt.key === 'Enter' && $input.trim() && @patch('/examples/todomvc/-1') && ($input = '');
	data: elements "></header><ul id="todo-list"><li role="button" tabindex="0" data-on-dblclick="evt.target === el && @get('/examples/todomvc/0')"><input id="todo-checkbox-0" type="checkbox" data-on-load="el.checked = true" data-on-click__prevent="@post('/examples/todomvc/0/toggle')"> <label for="todo-checkbox-0">Learn any backend language</label> <button class="error small" data-on-click="@delete('/examples/todomvc/0')"><iconify-icon icon="pixelarticons:close" noobserver=""></iconify-icon>

	<!doctype html>
	<html lang="en">
	<head>
	<meta charset="utf-8">
	<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no">

	<title>reveal.js</title>

	<link rel="stylesheet" href="dist/reset.css">
	<link rel="stylesheet" href="dist/reveal.css">

	keybinds clear-defaults=true {
	locked {
	bind "Ctrl g" { SwitchToMode "normal"; }
	bind "Ctrl o" { SwitchToMode "pane"; ToggleFocusFullscreen; SwitchToMode "locked"; }
	bind "Ctrl t" { SwitchToMode "tab"; }
	}
	pane {
	bind "left" { MoveFocus "left"; }
	bind "down" { MoveFocus "down"; }
	bind "up" { MoveFocus "up"; }

	use std-rfc/kv *

	alias ept = each {\|x\| print ($x \| table -e) }

	$env.config.edit_mode = 'vi'

	$env.config.table.header_on_separator = true
	$env.config.table.trim = {
	methodology: "truncating"
	truncating_suffix: "..."

	# Spawn xs serve in a temporary directory, run a closure, then cleanup
	def .tmp-spawn [closure: closure] {
	# Create a temporary directory
	let tmp_dir = (mktemp -d)
	print $"Created temp directory: ($tmp_dir)"

	let store_path = ($tmp_dir \| path join "store")

	try {
	# Create store directory

	# Spawn xs serve in a temporary directory, run a closure, then cleanup
	export def spawn-xs-test [closure: closure] {
	# Create a temporary directory
	let tmp_dir = (mktemp -d)
	print $"Created temp directory: ($tmp_dir)"

	let store_path = ($tmp_dir \| path join "store")

	try {
	# Create store directory

	# Create VPC
	VPC_ID=$(aws ec2 create-vpc \
	--cidr-block 10.0.0.0/28 \
	--tag-specifications 'ResourceType=vpc,Tags=[{Key=Project,Value=vibenv}]' \
	--query 'Vpc.VpcId' \
	--output text)

	# Disable DNS Support and Hostnames
	aws ec2 modify-vpc-attribute --vpc-id $VPC_ID --enable-dns-support "{\"Value\": false}"
	aws ec2 modify-vpc-attribute --vpc-id $VPC_ID --enable-dns-hostnames "{\"Value\": false}"