mepwec

MEdia Player WEb Control (control photo, audio and video play from local sources via web interface)

mepwec consists of three main components:

• a service component "playersvc" that starts, controls and kills players and is controllable via a pseudo terminal
• server-side lua code for the web interface, running under nginx web server
• web-page (Bootstrap4-based) with embedded javascript

In the development installation this setup is installed on a raspberry Pi4 connected to a TV screen.

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The service component "playersvc"

is startet with autostart as user "pi" from the graphical user user interface (lxterminal --command="<PATH TO APPLICATION>/playersvc"). The service component exposes its command interface over a pseudo terminal thats name can be read from /var/run/playersvc.pts. These commands can be issued to the service component:

Commands summary
 exit|ex|x|quit|q
 help|?
 open foto|photo|audio|video <FILE>
 enqueue|enq audio <FILE>
 close foto|photo|audio|video
 playerctl|play foto|photo|audio|video start|play|stop|pause|playerctl|play|previous|prev|next
 playerctl|play list
 playerctl|play status
 playerctl|play metadata
 playerctl|play allstatus
 playerctl|play slideshow|slides[ stop]
 display|disp on|off
 paths|path

playersvc uses Gwenview for photos, SMplayer for audio and VLC for video. /etc/playersvc.conf defines the root paths to media content which can be browsed through the web interface, e.g.:

pi@media-pi:~ $ cat /etc/playersvc.conf 
/<PATH TO PHOTOS DIRECTORY>/
/<PATH TO AUDIO CONTENT>/
/<PATH TO VIDEO DIRECTORIES>/

For separate testing the server components pseudo terminal can be connected to by some terminal application (e.g. minicom) and commands (as described above) can be issued.

The web server lua application (runs within nginx)

The server-side program installation consists of then file-walk and pts-interact lua-scripts. The path to the lua scripts has to be specified in the nginx configuration file nginx.conf: lua_package_path "/var/www/lua/?.lua;;";. The nginx default server configuration default defines the two locations / and /media which deliver the index page and the command interface.
The server-side lua scripts add file browsing functionality ls-command to the service component's functions.

Index page / user interface

index.shtml contains all client-side presentation stuff. This page uses SSI and is built on Bootstrap4 (at the moment nearly no work has been spent on design issues).

Example installation on Raspberry Pi

Following packages were to be installed additionally (debian 10.8):

vlc gwenview smplayer-themes smplayer-l10n playerctl mpris-remote xautomation xdotool
autofs screen minicom gcc make
lua-nginx-websocket lua-posix lua-filesystem lua-bit32 lua-bitop

"playersvc" had to be compiled on the Pi itself (just "make" playersvc-Files). Should be executable by "pi".

When started from graphical user interface "playersvc" is ready to handle commands (connect with e.g. minicom to the pseudo terminal, see above). To autostart "playersvc" an entry @lxterminal --command="<PATH TO APPLICATION>/playersvc" in ~/.config/lxsession/LXDE-pi/autostart (for user "pi") is needed.

Lua scripts and index page have to be installed into nginx as described above.