add 'README.install-node.js'.

README.install-node.js

@@ -0,0 +1,28 @@
+
+
+apt update && apt full-upgrade
+
+apt install curl \
+   gpg \
+   gnupg2 \
+   software-properties-common \
+   apt-transport-https \
+   lsb-release ca-certificates
+
+mkdir -p /etc/apt/keyrings
+curl -fsSL https://deb.nodesource.com/gpgkey/nodesource-repo.gpg.key | sudo gpg --dearmor -o /etc/apt/keyrings/nodesource.gpg
+
+
+# NODE_MAJOR=16
+# NODE_MAJOR=18
+# NODE_MAJOR=20
+#
+NODE_MAJOR=21
+
+echo "deb [signed-by=/etc/apt/keyrings/nodesource.gpg] https://deb.nodesource.com/node_$NODE_MAJOR.x nodistro main" | sudo tee /etc/apt/sources.list.d/nodesource.list
+
+apt update
+apt install nodejs
+
+node -v
+npm -v