Documenting CQRS ES

I have been looking for a decent template to document CQRS ES.
I think I have found one: https://github.com/tmorin/plantuml-libs

The following diagram:

This was generated using plantuml from the following source:

@startuml
' configures the library

' loads the library's bootstrap
!include https://raw.githubusercontent.com/tmorin/plantuml-libs/master/distribution/bootstrap.puml

!include https://raw.githubusercontent.com/tmorin/plantuml-libs/master/distribution/eventstorming/bootstrap.puml

' loads the package bootstrap

' include elements
include('eventstorming/Element/FacadeCommand')
include('eventstorming/Element/Command')
include('eventstorming/Element/Result')
include('eventstorming/Element/Event')
include('eventstorming/Element/DomainEvent')
include('eventstorming/Element/IntegrationEvent')
include('eventstorming/Element/Query')
include('eventstorming/Element/ReadModel')
include('eventstorming/Element/UserInterface')
include('eventstorming/Element/Aggregate')
include('eventstorming/Element/Service')
include('eventstorming/Element/Policy')
include('eventstorming/Element/Saga')
include('eventstorming/Element/Process')
include('eventstorming/Element/Timer')
include('eventstorming/Element/Person')
include('eventstorming/Element/System')
include('eventstorming/Element/Comment')

' display elements
FacadeCommand('FacadeCommand')
Command('Command')
Result('Result')
Event('Event')
DomainEvent('DomainEvent')
IntegrationEvent('IntegrationEvent')
Query('Query')
ReadModel('ReadModel')
UserInterface('UserInterface')
Aggregate('Aggregate')
Service('Service')
Policy('Policy')
Saga('Saga')
Process('Process')
Timer('Timer')
Person('Person')
System('System')
Comment('Comment')

@enduml

The advantage of this is that it does not require a local copy of the project.

The downside is that it requires an internet connection, and is at risk of the project being moved.
I can see myself making use of this.

I have forked this project so that I can have a guaranteed stable location and use a single file.

This reduces the above to:

@startuml

!include https://raw.githubusercontent.com/chriseyre2000/plantuml-libs/master/distribution/eventstorming/eventstorming.puml

' display elements
FacadeCommand('FacadeCommand')
Command('Command')
Result('Result')
Event('Event')
DomainEvent('DomainEvent')
IntegrationEvent('IntegrationEvent')
Query('Query')
ReadModel('ReadModel')
UserInterface('UserInterface')
Aggregate('Aggregate')
Service('Service')
Policy('Policy')
Saga('Saga')
Process('Process')
Timer('Timer')
Person('Person')
System('System')
Comment('Comment')

@enduml

Are The Inmates In Charge Of The Asylum?

The UK currently has a cost of living crisis. Inflation is going through the roof and the only think being done to influence this is to put up interest rates! The argument for this is that if credit becomes more expensive people will reduce what they are spending. Are economists so stuck in 1970’s models that they can see nothing else?

Credit card use is not rising because credit is cheap, they are rising because costs are escalating. Adding to the interest on mortgages and credit cards won’t help control this. This will drive workers to ask for larger pay rises and will fix the interest rate growth as permanent.

Fuel price rises have a massive effect across the whole supply chain. We had protests in the UK when petrol first reached 1 GBP per litre, we are now at around 1.85 GBP.

We have a leadership contest going on between two people who are denying reality and aiming for the votes of a very small electorate. Neither candidate has a sensible plan (or indeed a mandate). One wants to control inflation and the other wants to cut tax.

Craft GraphQL APIs in Elixir with Absinthe Part Four

Still working. through the examples.

Project is at https://github.com/chriseyre2000/absinthe_demo

Currently at df7c52f

Again there is a minor difference in the error message format, and the error is a 200 not a 400.

It’s interesting to see custom modification.


Now at the end of chapter 3

Chapter 4 introduces some useful extra structure, allowing the schema to be broken down into manageable pieces.

The next step will cover unions.

VS Code Custom Settings

This is my current VSCode settings:

{
    "files.autoSave": "afterDelay",
    "diffEditor.ignoreTrimWhitespace": false,
    "git.openDiffOnClick": false
}

It’s not much but it is a start.

Autosave is a must.
Opening the file from diff is much more sensible than assuming you want the diff.

Protobuf in Elixir

Protox is a great library to allow Protobuf to be used in Elixir.
While developing a span catcher for OpenTelemetry I found that I needed to decode a protobuf format message.

Here is the repo if you are interested:

https://github.com/chriseyre2000/span_eater

To construct the protobuf file I looked at the readme of opentelemetry_exporter, which pointed me to the protobuf definitions:

https://github.com/open-telemetry/opentelemetry-proto/tree/v0.11.0

I chose to simplify these into a single file (it’s not that large).

Protobuf is a wire format serializer. This means that if you send a Protobuf message any language that can use protobuf can read the message (provided that both side have the definition).

Given that this proto file has been implemented by a number of OpenTelemetry consumers it can be assumed to be stable.