Nginx Proxy Pass Issue - Docker, React and Express - reactjs

Question

I have a docker-compose set up that looks like this:
Containers:
Main nginx container gateway. The /todos/ route is proxy_passed to:
Another nginx container. This one proxy passes either to:
A React front end (for the todos app)
or
A node express api (which handles todo logic)
I'm trying to be able to call the todos api from the React app with process.env.PUBLIC_URL + "/api" in order to access the "/" route on my express api. However this isn't working, and I have to add another "/" to the React call to make it work - like this: process.env.PUBLIC_URL + /api/
Note: my React homepage is set to "/todos"
It's clearly a problem with how I'm doing the rewrites for the routes on Nginx, but I've tried every combination under the sun and can't get rid of the need for that trailing slash. Here are my Nginx configs:
The entry config:
upstream todosnginx {
server todosnginx;
}
server {
listen 80;
error_page 404 /404.html;
location / {
root /usr/share/nginx/html;
index index.html index.htm;
}
location /todos {
rewrite /todos/(.*) /$1 break;
proxy_intercept_errors on;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Proto $scheme;
proxy_pass http://todosnginx/;
}
}
And the todos nginx:
upstream todoclient {
server todoclient:3000;
}
upstream todoserver {
server todoserver:9000;
}
server {
listen 80;
location / {
proxy_pass http://todoclient/;
}
location /sockjs-node {
proxy_pass http://todoclient;
proxy_http_version 1.1;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection "Upgrade";
}
location /api {
rewrite /api/(.*) /$1 break;
proxy_pass http://todoserver/;
}
}
I've tried doing:
rewrite /api(.*) /$1 break;
in the todosnginx conf,
and
location /api/
and I've tried adding trailing slashes or deleting trailing slashes and many other combinations. It would be great if you knew where I was going wrong here.
Many thanks, R

Answer 1

rewrite /api(.*) $1 break;
if it doesn't work, post the logs.