octopi multicam support with raspicam, usbcam, and systemd

octopi-multicam-rpicam-usb-systemd.txt

roughly based on data from teaching tech tutorial at https://www.youtube.com/watch?v=pcFBsciSdEw

cd /boot/
sudo cp octopi.txt octopi-cam2.txt
cd /root/bin/
sudo cp webcamd webcamd2

modify the octopi.txt to default to raspicam by specifying camera="raspi"
modify the http option:
camera_http_options="-p 8080"

modify the octopi-cam2.txt to default to usb by specifying camera="usb"
modify the http option:
camera_http_options="-p 8081"

enable the raspi cam in raspi-config (Interface Options -> Camera)

create the startup files to use systemd

cd /etc/systemd/system
sudo cp webcamd.service webcamd2.service 
edit webcamd2 to point to the webcamd2 script and new log files
cat webcamd.service | sed -e's/webcamd/webcamd2/g' > webcamd2.service
sudo systemctl enable webcamd2.service

reboot to verify proper startup

modify haproxy

sudo vi /etc/haproxy/haproxy.cfg 
in "frontend public" add line 
use_backend webcam2 if { path_beg /webcam2/ }

create new section "webcam2" with content duplciated from "webcam"
backend webcam2
        reqrep ^([^\ :]*)\ /webcam2/(.*)     \1\ /\2
        server webcam2  127.0.0.1:8081
        errorfile 503 /etc/haproxy/errors/503-no-webcam.http
        
restart haproxy service with "sudo service haproxy restart"

Then add  multicam config to say "/webcam2/?action=stream"