Typically you would want to advertise exciting features when advertising a book. This time I want to prome boring releases.

This book includes a chapter on how we managed to take the drama out of releasing software. The software we released was exciting, but the actual releases were calm and measured. In one case we had a project manager prepare 30 scenarios, 27 bad and 3 good. In the end it went so well that none of the good scenarios applied. This was the digital release of the Cursed Child Script book.

Here is the book including a chapter on how we made the magic:

https://leanpub.com/development2019

Here is the guidance from the ICO

https://ico.org.uk/for-organisations/guide-to-data-protection/guide-to-the-general-data-protection-regulation-gdpr/accountability-and-governance/data-protection-by-design-and-default/#:~:text=The%20UK%20GDPR%20requires%20you,by%20design%20and%20by%20default’.

The idea is that any system that is being worked on requires data protection by design and default.

This includes:

Asking permission from the user to use their personal information. If they need to opt in this needs to be explicit rather than assumed. (There are some circustances where permission is not required, but you need to make the owner of the data aware).

You should also record the version of the privacy notice that they accepted. If the terms change to include additional usage then permission needs to be requested again before the data is used. Permission may also be withdrawn.

The use, storage and processes must be clear. Breaches of these need to be reported to the authorities and affected users.

Fully doing this is not simple. There are benefits. This will typically require personal data to be held in a single place which can simplify processes (less duplication and inconsistency). The need to understand your internal processes will also help. It forces good communication practices.

This looks interesting (https://eventmodeling.org/posts/what-is-event-modeling/)

If you want to report a bug to a (typically an open source) project. Follow these steps:

Check if the bug is already in the tracker. If so see if you could add a new test case to demonstrste the issue.

If it is not in the tracker create a simple test case that demonstrates the problem. Being able to recreate the issue makes it far easier to work on, making it far more likely to be picked to work on.

If you know how to fix the problem check that they accept Pull Requests and supply one. Allow the maintainer to edit it. Its likely that you are going to have missed some internal rules of the project.

Contributions to documentation are really appreciated by maintainers.

I have been following Codurance Fireside Chats (This is Episode 38).

Public Interest Note: I currently work for Codurance.

In this episode Sandro mentions that there is very little impact that you can have in 20% of the time.
I disagree, you can achieve a big impact with small changes over an extended period.

A good example came when I was supporting a production client system (in addition to other new development work). At the start of each day I would check the most frequent error listed in the logs for the past 24 hours. I would either try and resolve that error or improve the logging so that it can be resolved in the future. This would take less than 15 minutes per day.

There is an interesting statistical effect that happens in any distribution of events. It is extremely unlikely that everything happens at the same frequency. Certain items will dominate the sample.. Items that have identical frequencies are likely to be coupled (such as a system reporting the same error in two places). This is known as the Power Law

By using the Power Law I was able to significantly reduce the volume of error messages. The top 5 formed 50% of the overall messages so in a week the error volume had halved. This made the error logs easier to read. This process repeated for a few months and eventually there were only a handful of errors left that were so infrequent as to not be worth fixing. The next target was the warnings.

This makes a great principle: try and fix or improve one small thing each day. Even if the rest of the day is fairly monotonous at least you have that one small win. By the end of a year you will have hundreds of small wins which should be significant (even if some of them had to be rolled back).

Today I have found my diary has 10 meetings.

This is a reminder never to let this happen again.

This looks to be very interesting: https://github.com/burrito-elixir/burrito

I am going to see if I can make this work with home_server

This now has a yaml config file that allows you to specify the configuration.

https://github.com/chriseyre2000/home_server

So far I have been using it for a week. There have been a few false positives, but knowing when the VPN is down really helps.

apoc is a set of useful addons for Neo4j

I have been using brew to install neo4j on my machine.

brew install neo4j

This can be combined with

brew services.start neo4j
and

brew services stop neo4j

This typically installs a db on http://localhost:7474/browser

On mac via homebrew you need to look in /usr/local/Cellar/neo4j/4.4.5/libexec
To enable apoc copy apoc-4.4.0.3-core.jar from labs to plugins

You also need to change config/neo4j.conf

I have set the following value:

dbms.security.procedures.unrestricted=apoc.*

Restarting neo4j get this working.

Recently I have been turning to Elixir to solve some personal projects. It is a great general purpose language.

Like a lot of people I am mostly working from home. This involves working over a VPN to access some of the essential services that the client uses. The VPN client infrequently disconnects which is typically only noticed when one of these services become inaccessible.

It would be useful to be notified that this has happened. I found another Elixir project (https://github.com/navinpeiris/ex_unit_notifier) that had solved the notification problem but specifically for ex_unit. The trick is to install a CLI notification tool and execute that with appropriate parameters.

Once I had this I could use a simple webclient (HTTPoison) to check that a typical page exists that is only available behind the VPN.

This was wrapped in a specific GenServer that reran the check every minute. Having an Application and a Supervisor allows this to be started using iex -S mix.

This solved the problem but did require an iex session to be running. The next step was to use a Release to create something that could be run in the background. This only needed a simple `mix release`.

At this point I now had a service that can run as a background task. Shutting it down was a little clumsy – I’d need to find the shutdown script or manually kill it. It would be far simpler if there was a web interface so that it can be stopped via this (or a generic curl command).

Adding a trivial web interface was a simple matter of adding cowboy_plug to the application and configuring some routes. This allows the application to be cleanly shutdown using System.stop/0. Wrapping this in a task allows the web request to return a result before the shutdown.

Aside cowboy_plug has recently gained a dependency upon :telemetry, which needs to be added to your extra_applications. This section allows your application to request the optionally started Erlang application be run. Remember in Erlang terminology an application is more like a library rather than the whole project, which is called a release.

Now that I had a project that could do something in the background and notify the user the obvious thing was to make the GenServer more generic so that it can run any job on a schedule. This also allows me to keep the specific endpoints I am hitting outside a public repo.

This is the route that led to writing home_server. It now checks and notifies that the machine can connect to the internet (another intermittent issue) and has a config file that if present will monitor that URL and provide a custom message.

https://github.com/chriseyre2000/home_server

This project is still at an early stage. I plan to improve the config file as the current version is somewhat naive. It also needs a better solution for starting the processes from the config file.