PragProg Customers

Practical Microservices: Missing expected version in recordViewing function (page 37)

nicholasjhenry

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?

1 comment
#errata/book-practical-microservices
3 832 1

Marked As Solved

nicholasjhenry

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
Post #2

Where Next?

View thread on forum
View Practical Microservices's book portal
Post errata for this book
Post a suggestion for this book
Post a question about this book
Post a review about this book
Home PragProg Customers
#errata/book-practical-microservices
3 832 1
Last post

Popular Pragmatic Bookshelf topics Top

jeffmcompsci
PragProg Customers

Design and Build Great Web APIs: typo (page, 19, third bullet in URL list)
Title: Design and Build Great Web APIs - typo “https://company-atk.herokuapp.com/2258ie4t68jv” (page 19, third bullet in URL list) Typo:...
#pragprog#errata/book-design-and-build-great-web-apis
8 1941 7
New
GilWright
PragProg Customers

Apple Game Frameworks and Technologies: Screen image may be wrong (p 13)
Working through the steps (checking that the Info,plist matches exactly), run the demo game and what appears is grey but does not fill th...
#errata/book-apple-game-frameworks-and-technologies
11 1081 5
New
raul
PragProg Customers

Distributed Services with Go: Chapter 1 Suggestions
Hi Travis! Thank you for the cool book! :slight_smile: I made a list of issues and thought I could post them chapter by chapter. I’m rev...
#errata/book-distributed-services-with-go
2 1185 3
New
frasette
PragProg Customers

A Common-Sense Guide to Data Structures and Algorithms, Second Edition: erroneous extra space complexity (page400)
A Common-Sense Guide to Data Structures and Algorithms, Second Edition by Jay Wengrow @jaywengrow Hi, I have the paperback version of t...
#errata/book-a-common-sense-guide-to-data-structures-and-algorithms-second-edition
4 1180 2
New
swlaschin
PragProg Customers

Domain Modeling Made Functional: Missing diagram on page 18
The book has the same “Problem space/Solution space” diagram on page 18 as is on page 17. The correct Problem/Solution space diagrams ar...
#errata/book-domain-modeling-made-functional
1 1078 1
New
brunogirin
PragProg Customers

Python Testing with pytest, Second Edition: error when installing editable package (page 178)
When installing Cards as an editable package, I get the following error: ERROR: File “setup.py” not found. Directory cannot be installe...
#errata/book-python-testing-with-pytest-second-edition
0 1739 1
New
brunogirin
PragProg Customers

Python Testing with pytest, Second Edition: InterpreterNotFound error when running tox (page 150)
When running tox for the first time, I got the following error: ERROR: InterpreterNotFound: python3.10 I realised that I was running ...
#errata/book-python-testing-with-pytest-second-edition
0 1306 1
New
ggerico
PragProg Customers

Programming Machine Learning: some plot files are throwing error
I got this error when executing the plot files on macOS Ventura 13.0.1 with Python 3.10.8 and matplotlib 3.6.1: programming_ML/code/03_...
#question/book-programming-machine-learning
1 3055 5
New
gorkaio
PragProg Customers

Programming Phoenix LiveView: PentoWeb.LayoutView errata (56)
root_layout: {PentoWeb.LayoutView, :root}, This results in the following following error: no “root” html template defined for PentoWeb...
#errata/book-programming-phoenix-liveview
8 1094 4
New
dachristenson
PragProg Customers

Kotlin and Android Development featuring Jetpack: No activity_main.xml anymore
I just bought this book to learn about Android development, and I’m already running into a major issue in Ch. 1, p. 20: “Update activity...
#errata/book-kotlin-and-android-development-featuring-jetpack
0 2172 6
New

Other popular topics Top

Devtalk
General Dev>Dev Chat

HELLO WORLD (Introductions thread!)
Hello Devtalk World! Please let us know a little about who you are and where you’re from :nerd_face:
#community
481 6762 116
New
AstonJ
General Dev>Dev Chat

What are you listening to?
A thread that every forum needs! Simply post a link to a track on YouTube (or SoundCloud or Vimeo amongst others!) on a separate line an...
#community#music
202 5126 102
New
PragmaticBookshelf
General Dev>Learning Resources

Seven More Languages in Seven Weeks
Learn from the award-winning programming series that inspired the Elixir language, and go on a step-by-step journey through the most impo...
pragprog.com
#pragprog/elixir/julia/lua#published-book#factor/elm#minikanren/idris/book-seven-more-languages-in-seven-weeks
4 5862 0
New
AstonJ
General Dev>Hardware

GMK Serika Keycaps - Serika 2 available to order now!
I have seen the keycaps I want - they are due for a group-buy this week but won’t be delivered until October next year!!! :rofl: The Ser...
/keyboards#keycaps#mechanical-keyboards
9 5097 7
New
PragmaticBookshelf
Backend>Learning Resources

Programming WebRTC
Use WebRTC to build web applications that stream media and data in real time directly from one user to another, all in the browser. ...
pragprog.com
#pragprog#published-book/js#webrtc/book-programming-webrtc
27 6969 6
New
Maartz
General Dev>Dev Chat

Roc Language - a new purely functional programming language built for speed and ergonomics
Hi folks, I don’t know if I saw this here but, here’s a new programming language, called Roc Reminds me a bit of Elm and thus Haskell. ...
#programminguages#functional-programming
49 5164 14
New
PragmaticBookshelf
Backend>Learning Resources

Agile Web Development with Rails 7
Rails 7 completely redefines what it means to produce fantastic user experiences and provides a way to achieve all the benefits of single...
pragprog.com
#pragprog#web-development/ruby/rails#published-book/book-agile-web-development-with-rails-7
32 6600 9
New
PragmaticBookshelf
Community>In The Spotlight

Spotlight: Dmitry Zinoviev (Author) Interview and AMA!
Author Spotlight Dmitry Zinoviev @aqsaqal Today we’re putting our spotlight on Dmitry Zinoviev, author of Data Science Essentials in ...
#author-spotlight/python/book-complex-network-analysis-in-python/book-data-science-essentials-in-python/book-resourceful-code-reuse/book-pythonic-programming
33 5211 14
New
PragmaticBookshelf
Community>In The Spotlight

Spotlight: VM Brasseur (Author) Interview and AMA!
Author Spotlight: VM Brasseur @vmbrasseur We have a treat for you today! We turn the spotlight onto Open Source as we sit down with V...
#author-spotlight/book-forge-your-future-with-open-source
16 5051 11
New
RobertRichards
Game Dev>Chat

Hair Salon Games for Girls Fun
Hair Salon Games for Girls Fun Girls Hair Saloon game is mainly developed for kids. This game allows users to select virtual avatars to ...
#ios#android#unity#fun
2 3556 1
New
Back to top

Latest in Practical Microservices

Practical Microservices Portal ❯

PragProg Customers

Pragmatic Bookshelf PragProg Customers ❯

Latest on Devtalk

Devtalk ❯

We ❤️ helpful members!

We reward our most helpful members via our MOTM scheme - by giving away a whopping 25 books per year!

Member of the Month

Devtalk Sponsors

Pragmatic Bookshelf

Practical resources that improve the lives of professional developers.

Erlang Solutions

We build trusted fault-tolerant systems that scale to billions of users.

Honeybadger

Real-time error tracking, performance insights, and observability for devs.

EEF

Supporting innovation across the BEAM ecosystem.

coders51

We build reliable cloud platforms for business-critical systems.

Manning Publications

Develop your skills with books, videos, and courses.

AppSignal

Catch errors, track performance, monitor hosts and more.

WyeWorks

Enabling companies to succeed by building software people love.

Pragmatic Studio

Courses that move you from confusion to "Aha, now I get it!"

View all our sponsors ❯

Categories:

Sub Categories:

Popular Portals

Devtalk Sponsors

Pragmatic Bookshelf

Practical resources that improve the lives of professional developers.

Erlang Solutions

We build trusted fault-tolerant systems that scale to billions of users.

Honeybadger

Real-time error tracking, performance insights, and observability for devs.

EEF

Supporting innovation across the BEAM ecosystem.

coders51

We build reliable cloud platforms for business-critical systems.

Manning Publications

Develop your skills with books, videos, and courses.

AppSignal

Catch errors, track performance, monitor hosts and more.

WyeWorks

Enabling companies to succeed by building software people love.

Pragmatic Studio

Courses that move you from confusion to "Aha, now I get it!"

View all our sponsors ❯

We're in Beta

About us Mission Statement See our Roadmap