From ccd1852f65781a73f82ff8955e17b1ee9e13ec10 Mon Sep 17 00:00:00 2001
From: "D. Berge" <dberge@aaltronav.eu>
Date: Mon, 31 May 2021 02:10:23 +0200
Subject: [PATCH] Add Nunjucks rendered `get` filter.

Given an argument consisting of an array of objects and an attribute
name `attr`, it returns an array of all `attr` attributes.
---
 lib/www/server/lib/render.js | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/lib/www/server/lib/render.js b/lib/www/server/lib/render.js
index 5651f36..7194330 100644
--- a/lib/www/server/lib/render.js
+++ b/lib/www/server/lib/render.js
@@ -29,6 +29,10 @@ function njkCollect (entries, key, collectables) {
 	return out;
 }
 
+function njkGet (entries, key) {
+	return entries.map(i => i[key]);
+}
+
 function njkUnique (entries) {
 	return entries.filter((element, index, array) => array.indexOf(element) === index);
 }
@@ -81,6 +85,7 @@ async function render (data, template) {
 	nenv.addFilter('find', njkFind);
 	nenv.addFilter('unique', njkUnique);
 	nenv.addFilter('collect', njkCollect);
+	nenv.addFilter('get', njkGet);
 	nenv.addFilter('padStart', njkPadStart);
 	nenv.addFilter('timestamp', njkTimestamp);
 	nenv.addFilter('markdown', njkMarkdown);