A short note on how I wrote the server part for the 3D editor Cube Art Project, the server should save and display the work of users of the web version, giving them short URLs by the save button. At first I wanted to use Swift/PHP/Ruby/JS or some similar modern language for the backend, but after looking at the characteristics of my VPS, it was decided to write the server in C/C++.
First you need to install libfcgi on the server and the fcgi support module for your web server, example for Ubuntu and Apache:
sudo apt install libfcgi libapache2-mod-fcgid
Next, we configure the module in the config:
FcgidMaxProcessesPerClass – maximum number of processes per class, I set it to 1 process because I don’t expect a heavy load.
AddHandler fcgid-script .fcgi – the extension of the file with which the fcgi module should start.
Add to the config the folder from which cgi applications will be launched:
Next, we write an application in C/C++ with fcgi support, compile it, and copy it to the /var/www/html/cgi-bin folder.
Examples of code and build script:
https://gitlab.com/demensdeum/cube-art-project-server/-/blob/master/src/cubeArtProjectServer.cpp
https://gitlab.com/demensdeum/cube-art-project-server/-/blob/master/src/build.sh
After this you will need to restart your web server:
systemctl restart apache2
Next, set the necessary rights to execute the cgi-bin folder via chmod.
After that, your cgi program should work through the browser via the link, an example for the Cube Art Project server:
http://192.243.103.70/cgi-bin/cubeArtProject/cubeArtProjectServer.fcgi
If something doesn’t work, then look at the web server logs, or connect to the running process with a debugger, the debugging process should not differ from the debugging process of a regular client application.
Sources
https://habr.com/ru/post/154187/
http://chriswu.me/blog/writing-hello-world-in-fcgi-with-c-plus-plus/
Source code
https://gitlab.com/demensdeum/cube-art -project-server
