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Web.py + Lighttpd + sqlite3 on BeagleBone Black

debrew-ui

I’ve been working hard on a project lately called Debrew that adds a web interface to a CNC controller. I decided to go for Lighttpd as the web server, Web.py as the Python framework, and sqlite3 as the data base engine. Here is how I did it.

I’m going to write up the whole project in a different post, but I just wanted to post the instructions for getting a basic web interface going on BeagleBone Black. This post assumes using Angstrom (or similar OpenEmbedded flavour, I guess) as the distro. In the following instructions, I’m assuming starting from the Thing image. This image is very minimal, so it lacks stuff like Git..  The most important difference from a Debian based distro is perhaps the package handling system. The instructions are specific for Debrew, so just exchange your project for this.

Prerequities:

opkg install git
opkg install python-compile
opkg install wget
opkg install python-setuptools

Instructions for installing the software:

opkg install lighttpd
opkg install sqlite3
opkg install lighttpd-module-fastcgi
opkg install lighttpd-module-rewrite
opkg install lighttpd-module-alias
opkg install python-sqlite3

Install Web.py

cd /usr/src/
git clone git://github.com/webpy/webpy.git
cd webpy
python setup.py install

transfer python software

make debrew.py executable:

chmod +x /www/pages/debrew/debrew.py

Edit the lighttpd config file to enable serving Python files:

nano /etc/lighttpd.conf
enable mod_alias, mod_fastcgi, mod_rewrite by commenting out the # opn that line.

Add this to the end of the file:

fastcgi.server = ( ".py" =>
(( "socket" => "/tmp/fastcgi.socket",
"bin-path" => "/www/pages/debrew/debrew.py",
"max-procs" => 1,
"bin-environment" => (
"REAL_SCRIPT_NAME" => ""
),
"check-local" => "disable"
))
)

url.rewrite-once = (
"^/favicon.ico$" => "/static/favicon.ico",
"^/static/(.*)$" => "/static/$1",
"^/(.*)$" => "/debrew/debrew.py/$1",
)

The lighttpd systemd file is broken, so make sure it looks like this:

nano /lib/systemd/system/lighttpd.service

Should look like this:

[Unit]
Description=Lightning Fast Webserver With Light System Requirements
After=syslog.target

[Service]
EnvironmentFile=-/etc/sysconfig/lighttpd
ExecStart=/usr/sbin/lighttpd -D -f /etc/lighttpd.conf

[Install]
WantedBy=multi-user.target

Install Flup:

cd /usr/src
wget --no-check-certificate https://pypi.python.org/packages/source/f/flup/flup-1.0.tar.gz#md5=530801fe835fd9a680457e443eb95578
tar -vxf flup-1.0.tar.gz
cd flup-1.0/
python setup.py install

Restart lighttpd:

systemctl restart lighttpd

If there are problems during the development, make sure you check both /www/logs/lighttpd.error.log and syslog (journalctl).

Update: With the new Thing-image, this is already pre-installed.

8 Comments

  1. Is this related to what looked like a delta-bot coffee pourover setup you tweeted a photo of a while back? I’ve thought about making an automatic pourover setup that somehow emulates a person pouring the water, but using a cnc deltabot setup didn’t even cross my mind. Looks awesome!

    • Yes! Let me just finish the BBB flasher image for it and I will upload all files to a repo. OSHW FTW 😉

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