Garage security system

 Posted on February 26, 2017  |  Barnaby Gray

This project was to build a simple garage security system to alert of intruder access to the garage by notification over Wifi. Parts list Wemos D1 mini & mini protoboard The esp8266 is the workhorse of any project - it monitors the sensors and sends notifications over Wifi. I used the Arduino system with Platformio for development. For the small amount of circuitry required one of these tiny protoboards: ![D1 mini protoboard](/images/mini protoboard. [Read More]
esp8266  d1  security 

Amazon Dash doorbell

 Posted on December 14, 2016  |  Barnaby Gray

The Amazon Dash is a Wifi button originally intended for the ultra- lazy for reordering consumables from Amazon when you’re running low. It was going to £1 recently in Black Friday promotions, so I thought I’d have to snap one up. Normally they go for a not bank breaking £5, which you can recoup if you actually want to order one of the items once on them. When pressed it connects through Wifi to send a request to Amazon, then turns off - looks fit for repurposing for home automation! [Read More]
dash  iot  doorbell 

Cheerlights on an ESP8266 LED Wifi Controller

 Posted on December 8, 2016  |  Barnaby Gray

CheerLights is an “Internet of Things” project created by Hans Scharler where people volunteer to synchronise their lights all across the world to one colour. In a truly democratic fashion, the colour changes by anyone sending a tweet with a colour #cheerlights. Check out twitter to see it live: #cheerlights. I wanted to do something with the cheap esp8266 controllers you can get to control 3528 LED strips - it’s a ready built package with the voltage converter, ESP-12S processor and the MOSFETs necessary to switch 12V on the LED strips from the ESP 3. [Read More]
esp8266  3528  led  rgb  cheerlights 

Flashing custom Firmware to a Sonoff TH10/16

 Posted on October 30, 2016  |  Barnaby Gray

This is a tutorial about how to flash custom firmware onto the ESP8266 in the Sonoff Wireless Smart Switch. The Sonoff is a low cost mains relay with a fully customisable ESP8266 inside. Great for home automation hacking! Parts list Sonoff TH10 or TH16 A USB to TTL dongle CH340G (FT232RL or PL2303 based will also do), to flash the new firmware. A 3.3V breadboard power supply (only required for testing, safer than using mains! [Read More]
esp8266  sonoff  th10  espeasy 

Deploying a scikit-learn classifier to production

 Posted on April 4, 2016  |  Barnaby Gray

Scikit-learn is a great python library for all sorts of machine learning algorithms, and really well documented for the model development side of things. But once you have a trained classifier and are ready to run it in production, how do you go about doing this? There’s a few managed services that will do it for you, but for my situation these weren’t a good fit. We just wanted to deploy the model onto a modest sized Digital Ocean instance, as a REST API that can be externally queried. [Read More]
sklearn  scikit-learn  ml  machine learning  python 

Easy-peasy github releases for go projects using travis

 Posted on August 22, 2015  |  Barnaby Gray

A general theme of this blog is making life easier (or programmer laziness), so continuing in this vane this is a quick post on automated releases of go executables onto your github releases page. One of the strengths of go (which just got even easier with 1.5) is the ability to cross-compile self-contained executables - I find this particularly handy to get command line tools onto remote servers (though as with fine arts, wines, etc always be sure you trust the provenance of random executables you download…). [Read More]
go  golang  github  travis  travis-ci  release 

Automatically publishing Hugo blogs to S3

 Posted on July 25, 2015  |  Barnaby Gray

The process traditionally is: create a new blog article, edit it some, save. run hugo on the command line to generate the static site. copy/sync the public directory onto your webserver. Needing a webserver, build environment and text editor is a bit of hassle. It’s all a bit manual too. I’ve previously blogged about hosting on S3, but I wanted to see if a static blog could be managed entirely on free/hosted services. [Read More]
hugo  blog  s3  aws  codeship 

Hello, Hugo!

 Posted on July 25, 2015  |  Barnaby Gray

Been neglecting this blog for a while (check: blog cliché), but just migrated across from Pelican to Hugo, so thought this warrants a quick “check this out” post… Hugo? There’s a bit of a buzz around Hugo in the (albeit niche) world of static-blog-generation-tools. Though Pelican has been great, it feels like the world is slowly moving on from python. Or maybe I’m just a sucker for new stuff. :-) [Read More]
blog  hugo 

Elasticsearch as a smart cache

 Posted on February 18, 2014  |  Barnaby Gray

A novel use of Elasticsearch in the context of holiday search, not as a traditional store of persistent documents, but as a rolling cache of transient holiday packages. This puts unique demands on Elasticsearch in terms of index and deletion rate, concurrent to a high query rate. Figures below are from February 2014, so will have changed. Fancy a holiday? The travel industry works around the principal of ‘dynamic packaging’ of holidays. [Read More]
elasticsearch  caching 

docker fish completion

 Posted on February 8, 2014  |  Barnaby Gray

Command completion for docker in the fish shell

I’ve just released a handy completion definition for the fish shell.

fish?

Fish whilst not as popular as zsh/bash is a far better shell. Make the switch ;-)

install docker completion

$ mkdir ~/.config/fish/completions
$ wget https://raw.github.com/barnybug/docker-fish-completion/master/docker.fish -O ~/.config/fish/completions/docker.fish

example

% docker run -[TAB]
--attach          (Attach to stdin, stdout or stderr.)
...

% docker run -t -i [TAB]
    busybox:latest             (Image)
    ubuntu:12.04               (Image)

% docker run -t -i busybox:latest
/ #
docker  fish  shell  completion