updated make docs

rig/ctrl/docs.sh

@@ -1,6 +1,8 @@
 #!/usr/bin/env bash
 # Documentation: render the diagrams, and serve the pages from a throwaway nginx container.
 # Usage: docs.sh serve | graphs
+# Whose: DOCS_DIR, the docs/ of the folder `make docs` runs from (a project's launcher sets
+# it); unset, rig's own.
 # Notes: docs/notes/docs.md
 set -euo pipefail
 cd "$(dirname "$0")"
@@ -9,11 +11,13 @@ source ./lib/config.sh
 load_config
 
 REPO="$(cd .. && pwd)"
+DOCS="${DOCS_DIR:-$REPO/docs}"
+[ -d "$DOCS" ] && DOCS="$(cd "$DOCS" && pwd)"
 DOCS_PORT="${DOCS_PORT:-$((HTTP_PORT + 4))}"   # +4 sits inside this env's block
 
 serve() {
-    if [ ! -f "$REPO/docs/index.html" ]; then
-        echo "no docs/index.html" >&2
+    if [ ! -f "$DOCS/index.html" ]; then
+        echo "no index.html in $DOCS" >&2
         exit 1
     fi
     # One worker and no access log: a few static pages need no more, and the
@@ -32,13 +36,14 @@ http {
 }
 NGINX
     chmod 644 "$DOCS_CONF"
-    echo "docs for '$CLUSTER' on http://localhost:${DOCS_PORT}"
+    echo "docs of $DOCS"
+    echo "  for '$CLUSTER' on http://localhost:${DOCS_PORT}"
     echo "  (ctrl-c to stop; nothing is installed and nothing persists)"
     docker run --rm \
         --name "${CLUSTER}-docs" \
         -e NGINX_ENTRYPOINT_QUIET_LOGS=1 \
         -p "${DOCS_PORT}:80" \
-        -v "$REPO/docs:/usr/share/nginx/html:ro" \
+        -v "$DOCS:/usr/share/nginx/html:ro" \
         -v "$DOCS_CONF:/etc/nginx/nginx.conf:ro" \
         nginx:alpine
 }
@@ -51,13 +56,13 @@ graphs() {
     fi
     shopt -s nullglob
     local found=0 f out
-    for f in "$REPO"/docs/graphs/*.dot; do
+    for f in "$DOCS"/graphs/*.dot; do
         out="${f%.dot}.svg"
         echo "  graphviz $(basename "$f") → $(basename "$out")"
         dot -Tsvg "$f" -o "$out"
         found=1
     done
-    [ "$found" -eq 1 ] || echo "  no .dot files in docs/graphs/"
+    [ "$found" -eq 1 ] || echo "  no .dot files in $DOCS/graphs/"
 }
 
 case "${1:-serve}" in