Month: August 2020

Deploying my Homepage with Github Actions

While playing with the log analyser I mentioned in my post about building fail2ban rules, I accidentally overwrote the index.html file for my homepage.

After a bit of digging around and not being able to find a copy of it anywhere (it was probably on my old work laptop, so might be on the backup USB drive in the bottom draw…) I started to write a new one. To make sure I could always find a copy I decided I’d check it into GitHub.

As part of setting up the new repo I thought I’d have a look at the relatively new GitHib Actions that allow you to run jobs on your own hardware.

Actions are GitHubs implementation of a CI pipeline, you can attach an action to any number of events that happen on a repo e.g.

  • Post a welcome message when somebody new opens an issue
  • Run tests on any new pull requests
  • Deploy the project when code is merged into a specific branch

You can find a full list of triggers here.

It’s this last one that I’m going to use a trigger to deploy the new homepage when ever I commit to the master branch.

There is a list of pre-build Actions that can be used or extended to do all kinds of things or you can build your own. The documentation is here.

Actions are defined in a YAML file that you place in the .github/workflow directory of your repository.

name: PublishHomepage

on: [push]

jobs:
  deploy:
    name: Deploy Homepage
    runs-on: [self-hosted, linux]
    steps:
    - name: Checkout
      uses: actions/checkout@v2
      with:
        repository: 'hardillb/homepage'
        path: 'homepage'
    - run: bash ./homepage/scripts/deploy.sh

This attaches to the push trigger and asks that it is run on a self-hosted, linux machine. Where it will checkout the /hardillb/homepage repository and then execute the deploy.sh script found in the scripts directory of the repo.

Github supply runners for Windows/Linux/macOS on a range of architectures including ARM which means I can deploy one on the Raspberry Pi that hosts my website. Details of how to add a Action Runner to your specific project and download the package can be found here.

I went with running my own Action Runner on the same machine as the site is hosted because it means I don’t need to worry about setting up a custom ssh key and storing it as a secret so a cloud runner could access the device and upload the changed files. This way the script runs on the same machine and I can make sure the user has access rights to the right directory to copy the files to.

Another LoRa Temperature/Humidity Sensor

Having deployed my Adafruit Feather version of a Temperature/Humidity LoRa Sensor to make use of my The Things Network gateway it’s now time to build another sesnor, this time with a Raspberry Pi Zero.

Pi Supply LoRa node pHat with sensor

I have a Pi Supply LoRa node pHAT that adds the radio side of things, but I needed a sensor. The pHAT has a header on the right hand edge which pulls out the 3.3v, 2, 3, 4 and Gnd, pins from the pi.

These just happen to line up with the I2C bus. They are also broken out in the same order as used by the Pimoroni Breakout Garden series of I2C sensors which is really useful.

Pimoroni’s Breakout Garden offer a huge range of sensors and output devices in either I2C or SPI. In this case I grabbed the BME680 which offers temperature, pressure, humidity and air quality in a single package.

Pimoroni supply a python library to read from the sensor so it was pretty easy to combine this with python to drive the LoRa pHat

#!/usr/bin/env python3
from rak811 import Mode, Rak811
import bme680
import time

lora = Rak811()
lora.hard_reset()
lora.mode = Mode.LoRaWan
lora.band = 'EU868'
lora.set_config(app_eui='xxxxxxxxxxxxx',
                app_key='xxxxxxxxxxxxxxxxxxxxxx')
lora.join_otaa()
lora.dr = 5

sensor = bme680.BME680(bme680.I2C_ADDR_PRIMARY)
sensor.set_humidity_oversample(bme680.OS_2X)
sensor.set_temperature_oversample(bme680.OS_8X)
sensor.set_filter(bme680.FILTER_SIZE_3)

while True:
    if sensor.get_sensor_data():
        temp = int(sensor.data.temperature * 100)
        humidity = int(sensor.data.humidity * 100)
        foo = "{0:04x}{1:04x}".format(temp,humidity)
        lora.send(bytes.fromhex(foo))
        time.sleep(20)

lora.close()

I’m only using the temperature and humidity values at the moment to help keep the payload compatible with the feather version so I can use a single “port” in the TTN app.

I’ve put all the code for both this and the Feather version on GitHub here.

As well as the Pi Zero version I’ve upgraded the Feather with a 1200mAh LiPo battery and updated the code to also transmit the battery voltage so I can track battery life and work out how often I need to charge it.

Adding the battery also meant I could stick it in my bag and go for a walk round the village to see what sort of range I’m getting.

I’m currently using a little coil antenna on the gateway that is laid on it’s side, I’ll find something to prop it up with which should help. The feather is also only using a length of wire antenna so this could be seen as a worst case test.

It’s more than good enough for what I need right now, but it would be good to put a proper high gain one in then it might be useful to more people. It would be great if there was a way to see how many unique TTN applications had forwarded data through a gateway to see if anybody else has used it.