PragProg Customers

Real-Time Phoenix: use PubSub with implementation of Phoenix.Socket.Transport rather than channels (page 37)

rainforest

rainforest

Real-Time Phoenix: use PubSub with implementation of Phoenix.Socket.Transport rather than channels (page 37)

Hi, I’ve got a question about the implementation of PubSub when using a Phoenix.Socket.Transport behaviour rather than channels.
Before reading the book, I wrote a websocket server in Elixir using the Phoenix.Socket.Transport behaviour.

Since I’d like to use the PubSub to broadcast over multiple servers (using pg2 and libcluster to deliver messages also to remote nodes that are not in the same LAN), do I have to switch to channels to do that?

I ask it since in the book is not mentioned if you can build something like that also without channels.

Thanks in advance.

Andrea

3 comments
#question/book-real-time-phoenix#websockets#phoenixsocket#pubsub
0 1519 3

First Post!

sb8244

sb8244

Author of From Ruby to Elixir and Real-Time Phoenix

You will probably be successful with calling PubSub.subscribe inside of your Transport process. This will receive a handle_info callback whenever an event is received over PubSub. You must subscribe to specific topics, which the book goes into detail about.

Think of PubSub as a layer that Phoenix provides. It sits below Channels, and Channels are built on top of it. If you don’t use Channels you can still benefit from PubSub because it’s a completely separate layer. You just need to call the right functions to use it.

Post #2

Where Next?

View thread on forum
View Real Time Phoenix'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
question
websockets
phoenixsocket
pubsub
Home PragProg Customers
#question/book-real-time-phoenix#websockets#phoenixsocket#pubsub
0 1519 3
Last post

Popular Pragmatic Bookshelf topics Top

belgoros
PragProg Customers

Effective Testing with RSpec 3: Running Sequel migrations fails (page 84)
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...
#errata/book-effective-testing-with-rspec-3
4 1152 1
New
jamis
PragProg Customers

The Ray Tracer Challenge: various errata
The following is cross-posted from the original Ray Tracer Challenge forum, from a post by garfieldnate. I’m cross-posting it so that the...
#errata/book-the-ray-tracer-challenge
4 2381 3
New
jdufour
PragProg Customers

The Cucumber for Java Book:
Hello! On page xix of the preface, it says there is a community forum "… for help if your’re stuck on one of the exercises in this book… ...
#question/book-the-cucumber-for-java-book
3 1142 1
New
brian-m-ops
PragProg Customers

Python Testing with pytest, Second Edition: cards pip install error (page 12)
#book-python-testing-with-pytest-second-edition Hi. Thanks for writing the book. I am just learning so this might just of been an issue ...
#errata/book-python-testing-with-pytest-second-edition
4 1186 3
New
nicoatridge
PragProg Customers

Kotlin and Android Development: Could not get unknown property ‘kotlin_version’…
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...
/book-kotlin-and-android-development-featuring-jetpack
0 8047 6
New
hgkjshegfskef
PragProg Customers

The Ray Tracer Challenge: cannot pass scaling test (page 69-70)
The test is as follows: Scenario: Intersecting a scaled sphere with a ray Given r ← ray(point(0, 0, -5), vector(0, 0, 1)) And s ← sphere...
#question/book-the-ray-tracer-challenge
1 1085 4
New
digitalbias
PragProg Customers

Build a Weather Station with Elixir and Nerves: Problem connecting to Postgres with Grafana
Title: Build a Weather Station with Elixir and Nerves: Problem connecting to Postgres with Grafana on (page 64) If you follow the defau...
#errata/book-build-a-weather-station-with-elixir-and-nerves
0 1958 4
New
mert
PragProg Customers

Agile Web Development with Rails 7: page 152, page 153:
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...
#question/book-agile-web-development-with-rails-7
0 1228 4
New
andreheijstek
PragProg Customers

Modern front-end development for Rails, second edition - Struggling to get the first chapter to work
After running /bin/setup, the first error was: The foreman' command exists in these Ruby versions: That was easy to fix: gem install fore...
#errata/book-modern-front-end-development-for-rails
1 1111 3
New
redconfetti
PragProg Customers

Docker for Rails Developers - 'docker-machine' command deprecated (page 156)
Docker-Machine became part of the Docker Toolbox, which was deprecated in 2020, long after Docker Desktop supported Docker Engine nativel...
/book-docker-for-rails-developers#suggestion
0 896 0
New

Other popular topics Top

AstonJ
General Dev>Hardware

Which keyboard do you have?
If it’s a mechanical keyboard, which switches do you have? Would you recommend it? Why? What will your next keyboard be? Pics always w...
#hardware/keyboards#sticky#mechanical-keyboards
144 8820 50
New
dasdom
General Dev>Dev Chat

Standing Desks
No chair. I have a standing desk. This post was split into a dedicated thread from our thread about chairs :slight_smile:
#workspace#opinions
177 9043 77
New
PragmaticBookshelf
Game Dev>Learning Resources

Apple Game Frameworks and Technologies
Design and develop sophisticated 2D games that are as much fun to make as they are to play. From particle effects and pathfinding to soci...
pragprog.com
#pragprog#ios#game-dev#macos/swift#published-book#apple/book-apple-game-frameworks-and-technologies
30 6234 10
New
AstonJ
Backend>Questions

Erlang's not installing on macOS Big Sur "You are natively building Erlang/OTP for a later version of MacOSX than current version"
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 ...
#macos/erlang#big-sur#asdf
10 5914 8
New
AstonJ
General Dev>Hardware

BIIP MT3 Extended 2048 Custom Keycap Set (Drop)
This looks like a stunning keycap set :orange_heart: A LEGENDARY KEYBOARD LIVES ON When you bought an Apple Macintosh computer in the e...
/keyboards#apple#keycaps#mechanical-keyboards
14 6365 7
New
AstonJ
Backend>Chat

How to install Ruby 3 with ASDF
In case anyone else is wondering why Ruby 3 doesn’t show when you do asdf list-all ruby :man_facepalming: do this first: asdf plugin-upd...
/ruby#asdf
11 5679 4
New
PragmaticBookshelf
Backend>Learning Resources

Concurrent Data Processing in Elixir
Learn different ways of writing concurrent code in Elixir and increase your application's performance, without sacrificing scalability or...
pragprog.com
#pragprog/elixir#published-book/book-concurrent-data-processing-in-elixir
78 5131 24
New
DevotionGeo
General Dev>Questions

Do you prefer regular mechanical keyboards or low profile mechanical keyboards and why?
I have always used antique keyboards like Cherry MX 1800 or Cherry MX 8100 and almost always have modified the switches in some way, like...
/keyboards#mechanical-keyboards
27 3339 9
New
CommunityNews
General Dev>In The News

Review of Linux on Minisforum V3 AMD Ryzen Tablet
A Brief Review of the Minisforum V3 AMD Tablet. Update: I have created an awesome-minisforum-v3 GitHub repository to list information fo...
mudkip.me
#linux#review#amd
0 3361 0
New
PragmaticBookshelf
Backend>Learning Resources

Simplicity
Fight complexity and reclaim the original spirit of agility by learning to simplify how you develop software. The result: a more humane a...
pragprog.com
#pragprog#published-book/book-simplicity
10 4288 8
New
Back to top

Latest in Real-Time Phoenix

Real-Time Phoenix 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