React router and nginx giving Unexpected Token < - reactjs

Question

I have a react website which I am hosting inside a Docker container that is running Nginx, which I have running on Port 3000. I then have an instance of Nginx on my host machine, which I have a reverse proxy pointing to 127.0.0.1:3000.
Everything works fine, except I have a Twitter authentication call, which uses a callback. When the url points back to mysite.com/authenticated, this is asking Nginx for the path which of course falls over.
I have scoured the internet and have found many posts indicating I should have this in my nginx default file:
location / {
proxy_pass 127.0.0.1:3000;
try_files $uri $uri/ /index.html;
}
When I then navigate to my website, even the root, I am getting unexpected token < in the console errors.
What could be causing this issue?

Answer 1

Lets say you are calling external twitter api http://twitter/auth.com/twitter/authentication for authentication.
And in your react action file you have give url as /twitter/authentication to call.For this case following will be the configuration.
server {
location / {
proxy_pass http://127.0.0.1:3000;
}
location /twitter/authentication {
proxy_pass http://twitter/auth.com;
}
}
You have to write every location config inside server in nginx config.
After any modification in this config, you have restart nginx.

Answer 2

For me it was the link to app.js
<script src="/app/bundle.js"></script>
When I tried to reach my App at
http://localhost:8080/serv9090
the browser tried to find /app/bundle.js via
http://localhost:8080/app/bundle.js
Which is not found at localhost:8080 (nginx)
For a first try I changed
<script src="/app/bundle.js"></script>
to
<script src="http://localhost:8080/serv9090/app/bundle.js"></script>
This worked fine.
Hope this helped.

Answer 3

I solved this issue by adding the following into the nginx conf file:
location ~ .(static)/(js|css|media)/(.+)$ {
try_files $uri $uri/ /$1/$2/$3;
}