nicholasjhenry
Practical Microservices: Missing expected version in recordViewing function (page 37)
The function call for the message store is:
// video-tutorials/src/app/record-viewings/index.js
messageStore.write(streamName, viewedEvent)
but the function def is:
// video-tutorials/src/message-store/write.js
return (streamName, message, expectedVersion) => {
// implementation
}
Is there something I missing?
Marked As Solved
nicholasjhenry
Perhaps a lack in my knowledge of JavaScript and Message DB. Calling the function with the first two parameters will result in expectedVersion to be null. If write_message is invoked with a null then no version check is made. I can see how this behaviour would be desired for logging events compared to managing the state of an aggregate (DDD) where the expected version is important.
2
Popular Pragmatic Bookshelf topics
Following the steps described in Chapter 6 of the book, I’m stuck with running the migration as described on page 84:
bundle exec sequel...
New
Python Testing With Pytest - Chapter 2, warnings for “unregistered custom marks”
While running the smoke tests in Chapter 2, I get these...
New
Title: Web Development with Clojure, Third Edition - migrations/create not working: p159
When I execute the command:
user=> (create-...
New
I can’t setup the Rails source code. This happens in a working directory containing multiple (postgres) Rails apps.
With:
ruby-3.0.0
s...
New
Running mix deps.get in the sensor_hub directory fails with the following error:
** (Mix) No SSH public keys found in ~/.ssh. An ssh aut...
New
Hi, I have just acquired Michael Fazio’s “Kotlin and Android Development” to learn about game programming for Android. I have a game in p...
New
Title: Build a Weather Station with Elixir and Nerves: Problem connecting to Postgres with Grafana on (page 64)
If you follow the defau...
New
AWDWR 7, page 152, page 153:
Hello everyone,
I’m a little bit lost on the hotwire part. I didn’t fully understand it.
On page 152 @rub...
New
Hi, I’m working on the Chapter 8 of the book.
After I add add the point_offset, I’m still able to see acne:
In the image above, I re...
New
Getting an error when installing the dependencies at the start of this chapter:
could not compile dependency :exla, "mix compile" failed...
New
Other popular topics
Hello Devtalk World!
Please let us know a little about who you are and where you’re from :nerd_face:
New
New
Just done a fresh install of macOS Big Sur and on installing Erlang I am getting:
asdf install erlang 23.1.2
Configure failed.
checking ...
New
Use WebRTC to build web applications that stream media and data in real time directly from one user to another, all in the browser.
...
New
Biggest jackpot ever apparently! :upside_down_face:
I don’t (usually) gamble/play the lottery, but working on a program to predict the...
New
A few weeks ago I started using Warp a terminal written in rust. Though in it’s current state of development there are a few caveats (tab...
New
We’ve talked about his book briefly here but it is quickly becoming obsolete - so he’s decided to create a series of 7 podcasts, the firs...
New
New
zig/http.zig at 7cf2cbb33ef34c1d211135f56d30fe23b6cacd42 · ziglang/zig.
General-purpose programming language and toolchain for maintaini...
New
Fight complexity and reclaim the original spirit of agility by learning to simplify how you develop software. The result: a more humane a...
New
Categories:
Sub Categories:
Popular Portals
- /elixir
- /rust
- /wasm
- /ruby
- /erlang
- /phoenix
- /keyboards
- /python
- /js
- /rails
- /security
- /go
- /swift
- /vim
- /clojure
- /java
- /emacs
- /haskell
- /svelte
- /typescript
- /onivim
- /kotlin
- /c-plus-plus
- /crystal
- /tailwind
- /react
- /gleam
- /ocaml
- /flutter
- /elm
- /vscode
- /ash
- /html
- /opensuse
- /zig
- /centos
- /deepseek
- /php
- /scala
- /react-native
- /lisp
- /textmate
- /sublime-text
- /nixos
- /debian
- /agda
- /deno
- /django
- /kubuntu
- /arch-linux
- /nodejs
- /spring
- /revery
- /ubuntu
- /manjaro
- /julia
- /diversity
- /lua
- /markdown
- /quarkus









