Docker Express App : Nginx 504 Gateway Time-out response - docker

Question

I'm newbie in Docker and I'm following this tutorial:
Learn Docker - DevOps with Node.js & Express https://www.youtube.com/watch?v=9zUHg7xjIqQ
I'm completely stuck in the section about adding a new service, 'nginx' proxy server
My computer is a MacBook running macOS Big Sur v.11.7
Here it is the relevant code:
nginx > default.conf
server {
listen 80;
location /api {
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header Host $http_host;
proxy_set_header X-NginX-Proxy true;
proxy_pass http://node-app:3000;
proxy_redirect off;
}
}
docker-compose.yml
version: "3"
services:
nginx:
image: nginx:stable-alpine
ports:
- "3000:80"
volumes:
- ./nginx/default.conf:/etc/nginx/conf.d/default.conf:ro
node-app:
build: .
environment:
- PORT=3000
depends_on:
- mongo
mongo:
image: mongo
environment:
- MONGO_INITDB_ROOT_USERNAME=root
- MONGO_INITDB_ROOT_PASSWORD=example
volumes:
- mongo-db:/data/db
redis:
image: redis
volumes:
mongo-db:
Dockerfile
FROM node:16
WORKDIR /app
COPY package.json .
ARG NODE_ENV
RUN if [ "$NODE_ENV" = "development" ]; \
then npm install; \
else npm install --only=production; \
fi
COPY . ./
ENV PORT 3000
EXPOSE $PORT
CMD ["node", "index.js"]
index.js
const express = require("express");
const app = express();
const mongoose = require("mongoose");
const {
MONGO_USER,
MONGO_PW,
MONGO_PORT,
MONGO_IP,
REDIS_URL,
REDIS_PORT,
SESSION_SECRET,
} = require("./config/config");
const connectWithRetry = () => {
mongoose
.connect(
`mongodb://${MONGO_USER}:${MONGO_PW}#${MONGO_IP}:${MONGO_PORT}/?authSource=admin`
)
.then(() => console.log("Succesfully connected to DB"))
.catch((e) => {
console.log(e);
setTimeout(connectWithRetry, 5000);
});
};
connectWithRetry();
const session = require("express-session");
const redis = require("redis");
let RedisStore = require("connect-redis")(session);
let redisClient = redis.createClient({
legacyMode: true,
socket: {
port: REDIS_PORT,
host: REDIS_URL,
},
});
redisClient.connect().catch(console.error);
const sessionConfig = {
store: new RedisStore({ client: redisClient }),
secret: SESSION_SECRET,
secure: false,
resave: false,
saveUninitialized: false,
cookie: {
httpOnly: true,
expires: Date.now + 1000 * 3600 * 24 * 7,
maxAge: 1000 * 3600 * 24 * 7,
},
};
app.use(session(sessionConfig));
app.use(express.json());
const port = process.env.PORT || 3000;
app.get("/api/v1", (req, res) => {
res.send("Home Page");
});
app.listen(port, () => {
console.log(`Serving in port: ${port}`);
});
When I place this simple request:
http://localhost:3000/api/v1/
I get this reponse from the browser:
504 Gateway Time-out
And this error message from the 'nginx' container:
2022/11/30 03:11:31 [error] 22#22: *20 upstream timed out (110: Operation timed out) while connecting to upstream, client: 192.168.0.1, server: , request: "GET /api/v1/ HTTP/1.1", upstream: "http://23.221.222.250:3000/api/v1/", host: "localhost:3000"
192.168.0.1 - - [30/Nov/2022:03:11:31 +0000] "GET /api/v1/ HTTP/1.1" 504 569 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/107.0.0.0 Safari/537.36" "-"`
I really appreciate any help here.