init rig

rig/ctrl/docs.sh

@@ -0,0 +1,58 @@
+#!/usr/bin/env bash
+# Documentation: render the diagrams, and serve the pages.
+#
+# The docs are the instructions for building the cluster, so they must work
+# BEFORE anything else exists. That rules out serving them from the cluster, and
+# it rules out python -m http.server too — a minimal Debian has no python3. What
+# it does have, by definition, is Docker: the single prerequisite rig already
+# demands. So a throwaway nginx container serves a read-only bind mount.
+#
+# Rendered SVGs are committed alongside their .dot sources for the same reason:
+# the pages have to read on a machine with no Graphviz installed.
+#
+# Usage: docs.sh serve | graphs
+set -euo pipefail
+cd "$(dirname "$0")"
+
+source ./lib/config.sh
+load_config
+
+REPO="$(cd .. && pwd)"
+DOCS_PORT="${DOCS_PORT:-$((HTTP_PORT + 4))}"   # +4 sits inside this env's block
+
+serve() {
+    if [ ! -f "$REPO/docs/index.html" ]; then
+        echo "no docs/index.html" >&2
+        exit 1
+    fi
+    echo "docs for '$CLUSTER' on http://localhost:${DOCS_PORT}"
+    echo "  (ctrl-c to stop; nothing is installed and nothing persists)"
+    docker run --rm \
+        --name "${CLUSTER}-docs" \
+        -p "${DOCS_PORT}:80" \
+        -v "$REPO/docs:/usr/share/nginx/html:ro" \
+        nginx:alpine
+}
+
+graphs() {
+    if ! command -v dot >/dev/null 2>&1; then
+        echo "graphviz not found — install with: sudo apt install graphviz" >&2
+        echo "(only needed to re-render; the committed .svg files already work)" >&2
+        exit 1
+    fi
+    shopt -s nullglob
+    local found=0 f out
+    for f in "$REPO"/docs/graphs/*.dot; do
+        out="${f%.dot}.svg"
+        echo "  graphviz $(basename "$f") → $(basename "$out")"
+        dot -Tsvg "$f" -o "$out"
+        found=1
+    done
+    [ "$found" -eq 1 ] || echo "  no .dot files in docs/graphs/"
+}
+
+case "${1:-serve}" in
+    serve)  serve ;;
+    graphs) graphs ;;
+    *)      echo "usage: $0 [serve|graphs]" >&2; exit 1 ;;
+esac