Limit log size and add pre-logon message (#40)

Fixes #35 and #12

.github/workflows/main.yml

@@ -67,6 +67,8 @@ jobs:
         commands: |
           chmod +x ${{matrix.script}}
           ${{ matrix.script }}
+          chmod +x ./install_common.sh
+          ./install_common.sh
           echo "${{ github.ref_name }};${{ matrix.name }}" > /opt/photonvision/image-version
 
     - name: Compress built image

files/issue.txt

@@ -0,0 +1,19 @@
+
+              #######                   PhotonVision is the free, fast, and 
+           #############                easy-to-use computer vision solution 
+         #################              for the FIRST Robotics Competition. 
+       ######        ######   :::       
+      #####            ##*::::::::::    To configure PhotonVision, open:
+     #####     :::::::::::::::::::      
+     #### :::::::::::    ###            http://photonvision.local:5800
+     ####                ####           
+    ####                 ####           using a computer on the same network 
+    #### ::              ###            as this device.
+     #### :::::::       ####            
+     ####     ::::::::  ####            Documentation is available at: 
+     #####         ::::::::    :        
+      ######        ####:::::::::       https://docs.photonvision.org/
+       ##################    ::::::     
+         ##############                 
+           #########                    
+

install_common.sh

@@ -0,0 +1,19 @@
+#!/bin/bash -v
+
+# Do additional tasks that are common across all images, 
+# but not suitable for inclusion in install.sh
+echo "Running install_common.sh"
+
+# Limit the maximum length of systemd-journald logs
+mkdir -p /etc/systemd/journald.conf.d
+cat > /etc/systemd/journald.conf.d/60-limit-log-size.conf <<EOF
+# Added by Photonvision to keep the logs to a reasonable size
+[Journal]
+SystemMaxUse=100M
+EOF
+
+# Add a helpful message to the logon screen
+# ASCII Art generated by: https://www.asciiart.eu/image-to-ascii
+cp -f ./files/issue.txt /etc/issue
+cp -f /etc/issue /etc/issue.net
+sed -i 's/#Banner none/Banner \/etc\/issue.net/g' /etc/ssh/sshd_config