Lab inventory web interface

This repo is my personal web interface that I use to keep an inventory of my components, boards, SBC, e.t.c. for my home lab. The web interface is just a simple html/php/javascript code that executes queries in an SQLite3 database. The web interface also supports to send aREST commands to an ESP8266 that drives a WS2812b RGB LED strip. You can also choose another LED strip type in the ESP8266 firmware. More details regarding the firmware are later in this README and also in my blog port.

Note: There is also a blog post here with more details on how to build the project: https://www.stupid-projects.com/component-database-with-led-indicators/

Build firmware

To build the firmware you need platform.io. I'm running an Ubuntu 18.04.3LTS and I'm using Visual Studio Code with the platform.io extension. In this case you just need to open the project and then open a terminal by clicking View -> Terminal and then run those two commands:

pio lib update
pio lib install

This will install all the dependency libraries. Now you can build the firmware

Connect ESP8266

Now you need to connect everything together, which is quite simple. Use a +5V power supply that can provide the needed power and current for the LED strip. Now, connect the +5V and GND of the WS2812B strip to the PSU and then also do the following connections:

ESP8266	WS2812B
D2	Din
GND	GND

Also connect the D1 pin of the NodeMCU to GND via a 4K7 resistor. This pin is used for reseting the configuration to the default values and when it's connected to the GND then it's the normal operation and when is connected to +3V3 then if you reset the ESP8266 then the default configuration will be loaded. Always remember to connect the resistor again to the GND after reseting to defaults.

Finally connect a USB cable to ESP8266 and your computer or a USB power supply in normal use.

aREST commands

The supported aREST commands are the following ones

Command	Description
led_index	The index of the LED to turn ON
led_on_color	The integer value of the CRGB color for ON
led_off_color	The integer value of the CRGB color for OFF
led_on_timeout	The integer value of the LED timeout in seconds
led_ambient	The integer value of the CRGB color for the ambient mode
enable_ambient	Enables/disables the ambient mode
wifi_ssid	The WiFi SSIDwifi_passwordThe WiFi password

The color CRGB values can be calculated by converting the HEX value to integer for each supported color in this file: .pio/libdeps/nodemcuv2/FastLED_ID126/pixeltypes.h

Assuming that the ESP8266 IP address is 192.168.0.42, then to send an aREST command, open a web browser and enter this url to lit the first LED in the strip

http://192.168.0.42/led_index?params=0

Or if you want to set the led_on_color to CRGB::SkyBlue (which according to pixeltypes.h is 0x87CEEB in HEX or 8900331 in integer), then send this command:

http://192.168.0.42/led_on_color?params=8900331

Similarly, you can execute any spported command.

ambient mode

When ambient mode is enabled then all the LEDs in the strip are lit permanately with the color defined in the the led_ambient aREST variable. Assuming that the ESP8266 IP address is 192.168.0.42, then to enable the ambient mode, open a web browser and enter this url:

http://192.168.0.42/enable_ambient?params=1

And to disable it:

http://192.168.0.42/enable_ambient?params=0

DB.Location

The Location field of the database table (tbl_parts) can be used in two different ways:

1. If it's just a number then it represents a LED index on the RGB strip.
2. If it starts with any letter, then the html web interface, will display this information on the item list.

For example, if Location is 32 then the web interface will display a button, which when it's pressed it will send the led_index command with that number.

If Location is L32 or Cabinet 3 or Drawer 1, then the web interface will display this string in the item list with the Location: prefix. So, it will became:

Location: L32

Install SQLite browser

DB Browser for SQLite is an open source browser with a GUI that you can use to edit manually your database. You can find installers in the previous link, but in case you're using Ubuntu like me, then you can install it with apt

sudo apt install sqlitebrowser

Testing the interface with Docker

To test the web interface or develop new features you don't have to install a web server from the scratch. Instead you can use the included Dockerfile to build an image that includes lighttpd, php-7.4 and sqlite3. To build the image, then from the root repo directory run this command:

docker build --build-arg WWW_DATA_UID=$(id -u ${USER}) -t lighttpd-server docker-lighttpd-php7.4-sqlite3/

Note: Your host's user uid need to be the same with the www-data user in the image. By default the www-data uid is set to 1000. If your host user has a different uid, then you need to set the proper uid in the build command by setting the WWW_DATA_UID arg. The above script will automatically extract your user's uid, but in case you want a specific one then just override the WWW_DATA_UID.

After you build the image then you can use docker-compose with the provided scripts/docker-compose.yml file to bring up a web server and start experimenting. To that you need first to install docker-compose by following this guide here. Then you can run this command:

docker-compose up

The above yml file will mount the www/lab folder to the /var/www/html/lab and it will replace the default /etc/lighttpd/lighttpd.conf file with the one in the repo's www/lighttpd.conf.

This step is not necessary, but if you need to get acccess in to the console of the running container then run this command:

docker-compose exec webserver /bin/sh

Finally, in order to test the webserver you need the container's IP address. You can find that with two different ways. One way is to find the ip using docker tool.

docker ps -a

This command will output all the running containers. You need to extract the CONTAINER ID of the web-server (e.g.f539671b84fd) and then use this to inspect the container with this command:

docker inspect f539671b84fd

This will print several information but what you need is the NetworkSettings -> Networks -> IPAddress value.

The other way to find the ip is to connect to the container's console and run ifconfig.

docker-compose exec webserver /bin/sh
ifconfig

Licence

For all the parts of code that's mine the lience is MIT. Be aware that other libraries used in the code may have different licence.