Add web server to make it easier to generate cards from CNC node

.gitignore

@@ -3,6 +3,7 @@
 *~
 prepare-vms/tags
 prepare-vms/infra
+prepare-vms/www
 slides/*.yml.html
 slides/autopilot/state.yaml
 slides/index.html

prepare-vms/lib/commands.sh

@@ -33,9 +33,14 @@ _cmd_cards() {
         ../../lib/ips-txt-to-html.py settings.yaml
     )
 
+    ln -sf ../tags/$TAG/ips.html www/$TAG.html
+    ln -sf ../tags/$TAG/ips.pdf www/$TAG.pdf
+
     info "Cards created. You can view them with:"
     info "xdg-open tags/$TAG/ips.html tags/$TAG/ips.pdf (on Linux)"
     info "open tags/$TAG/ips.html (on macOS)"
+    info "Or you can start a web server with:"
+    info "$0 www"
 }
 
 _cmd deploy "Install Docker on a bunch of running VMs"
@@ -568,6 +573,18 @@ EOF"
     sudo systemctl start webssh.service"
 }
 
+_cmd www "Run a web server to access card HTML and PDF"
+_cmd_www() {
+    cd www
+    IPADDR=$(curl -sL canihazip.com/s)
+    info "The following files are available:"
+    for F in *; do
+        echo "http://$IPADDR:8000/$F"
+    done
+    info "Press Ctrl-C to stop server."
+    python -m http.server
+}
+
 greet() {
     IAMUSER=$(aws iam get-user --query 'User.UserName')
     info "Hello! You seem to be UNIX user $USER, and IAM user $IAMUSER."

prepare-vms/www/README

@@ -0,0 +1,4 @@
+This directory will contain symlinks to HTML and PDF files for the cards
+with the IP address, login, and password for the training environments.
+
+The file "index.html" is empty on purpose: it prevents listing the files.