Initial commit

docker-entrypoint.d/10-config.sh

@@ -0,0 +1,26 @@
+#!/bin/sh
+# Run by the nginx image's entrypoint before nginx starts. Writes the runtime
+# config the SPA reads as window.__APP_CONFIG__, so one image serves every
+# environment. To expose a new env var to the browser, add its name to VARS.
+# Never put secrets here: everything in config.js is public.
+set -eu
+
+VARS="API_BASE_URL APP_NAME"
+OUT=/usr/share/nginx/html/config.js
+
+: "${API_BASE_URL:=/api}"
+: "${APP_NAME:=app}"
+
+json_escape() {
+  printf '%s' "$1" | sed -e 's/\\/\\\\/g' -e 's/"/\\"/g'
+}
+
+body=""
+for name in $VARS; do
+  eval "value=\${$name:-}"
+  [ -n "$body" ] && body="$body,"
+  body="$body\"$name\":\"$(json_escape "$value")\""
+done
+
+printf 'window.__APP_CONFIG__ = {%s};\n' "$body" > "$OUT"
+echo "10-config.sh: wrote $OUT"