PragProg Customers

Programming WebRTC: How to configure CORS for the signaling server

huynh

huynh

Programming WebRTC: How to configure CORS for the signaling server

@karlstolley

I want to run the signaling server and the front-end (e.g., basic_p2p app) on separate ports.

From the client side, I get this “CORS missing allow origin” when connecting to the server.
How to solve that issue?

What I tried so far (and that didn’t work):

// server.js
const cors = require("cors");
const app = express();
app.use(cors());
1 comment
#question/book-programming-webrtc
0 292 1

Marked As Solved

karlstolley

karlstolley

Author of WebRTC: Build Real-Time Web Applications in the Browser

Hi Huynh!

There’s a couple of ways to handle this. One would be to worry about CORS only on the socket server. Have a look at Socket.io docs at Handling CORS | Socket.IO

Or, to continue your method of working directly with Express, have a close look at their documentation, including Express cors middleware

If you’re not yet skilled with using a tool like curl, that will help you determine the headers coming back from both your app and signaling servers, and help you figure out where additional adjustments or configuration is needed.

Post #2

Where Next?

View thread on forum
View Programming Webrtc'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
Home PragProg Customers
#question/book-programming-webrtc
0 292 1
Last post

Popular Pragmatic Bookshelf topics Top

telemachus
PragProg Customers

Warnings in Python Testing With Pytest Chapter 2
Python Testing With Pytest - Chapter 2, warnings for “unregistered custom marks” While running the smoke tests in Chapter 2, I get these...
#pragprog#errata/book-python-testing-with-pytest
5 2075 1
New
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 1931 7
New
Alexandr
PragProg Customers

Programming Machine Learning: Incorrect formula
Hi everyone! There is an error on the page 71 in the book “Programming machine learning from coding to depp learning” P. Perrotta. You c...
#errata/book-programming-machine-learning
5 1335 4
New
mikecargal
PragProg Customers

Hands-on Rust: can_place logic is "inside out"
Title: Hands-On Rust (Chapter 11: prefab) Just played a couple of amulet-less games. With a bit of debugging, I believe that your can_p...
#errata/book-hands-on-rust
22 1622 20
New
cro
PragProg Customers

Programming Phoenix LiveView: P27, live_path confusion
I am working on the “Your Turn” for chapter one and building out the restart button talked about on page 27. It recommends looking into ...
#question/book-programming-phoenix-liveview
7 3492 14
New
Chrichton
PragProg Customers

Programming Phoenix LiveView: B03 (page 56-57) auth exercise
Dear Sophie. I tried to do the “Authorization” exercise and have two questions: When trying to plug in an email-service, I found the ...
#question/book-programming-phoenix-liveview
1 1180 3
New
AufHe
PragProg Customers

Agile Web Development with Rails 7: page 113 - Seeing the list of products
I’m a newbie to Rails 7 and have hit an issue with the bin/Dev script mentioned on pages 112-113. Iteration A1 - Seeing the list of prod...
#question/book-agile-web-development-with-rails-7
0 2623 9
New
rainforest
PragProg Customers

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 ...
#question/book-real-time-phoenix#websockets#phoenixsocket#pubsub
0 1519 3
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 1090 4
New
davetron5000
PragProg Customers

Bug with dx/build - how to workaround until fix is up
Hello faithful readers! If you have tried to follow along in the book, you are asked to start up the dev environment via dx/build and ar...
#errata/book-ruby-on-rails-background-jobs-with-sidekiq
3 1158 19
New

Other popular topics Top

AstonJ
Science/Tech>Tech Chat

What are you watching?
Or looking forward to? :nerd_face:
#community
485 12328 258
New
DevotionGeo
Backend>Questions

Can someone explain the -t option/flag in docker run command?
I know that -t flag is used along with -i flag for getting an interactive shell. But I cannot digest what the man page for docker run com...
#docker
7 9055 2
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
rustkas
Backend>Chat

Using Regular Expressions in Erlang
Intensively researching Erlang books and additional resources on it, I have found that the topic of using Regular Expressions is either c...
/erlang#regular-expressions
91 5416 43
New
AstonJ
Data Science

Can AI/ML predict a lottery win?
Biggest jackpot ever apparently! :upside_down_face: I don’t (usually) gamble/play the lottery, but working on a program to predict the...
#ai#machine-learning
19 3496 10
New
husaindevelop
Android>Questions

Clipboard readtext not working in android webview
Inside our android webview app, we are trying to paste the copied content from another app eg (notes) using navigator.clipboard.readtext ...
#android#clipboard
1 4678 0
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
AstonJ
AI>In The News

DeepSeek (671B) running on a cluster of 8 Mac Mini Pros with 64GB RAM each
This is cool! DEEPSEEK-V3 ON M4 MAC: BLAZING FAST INFERENCE ON APPLE SILICON We just witnessed something incredible: the largest open-s...
#ai#macs/deepseek
0 5576 1
New
AstonJ
AI>Chat

How to: Run DeepSeek on Mac, Windows, and Linux!
This is a very quick guide, you just need to: Download LM Studio: https://lmstudio.ai/ Click on search Type DeepSeek, then select the o...
#macs/deepseek#guides#lm-studio
14 7706 10
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 2088 1
New
Back to top

Latest in Programming WebRTC

Programming WebRTC 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