Pass environment variable through PM2 to NextJS - shell

Question

I have 2 package.json scripts that look like this:
"start": "next start -p $PORT",
"pm2_staging": "pm2 restart ecosystem.config.js --env staging",
And an ecosystem.config.js that looks like this:
module.exports = {
apps: [
{
name: 'test.co.uk',
script: 'npm',
args: 'start',
env_staging: {
API: 'staging',
NODE_ENV: 'production',
PORT: 3001,
},
},
],
};
I then run the following:
TEST_VAR='test' npm run pm2_staging
I would expect the following to happen:
The PM2 restart command fires
ecosystem.config.js fires the npm start command and sets some environment variables
The app starts and all env vars are available, including TEST_VAR (set in the original command)
What actually happens is all the env vars from the ecosystem are correctly set, but TEST_VAR is not available in the app. Why is this and how do I go about setting secret keys from CI tools if I can't do this?

Answer 1

I ran into the same problem tonight. After looking every where I found the config needed. The env variable needs to go in your ecosystem.config.js like below. In my case I put it at the root of my server
module.exports = {
apps : [{
name: 'nextjs',
script: 'yarn',
args:"start",
cwd:"/var/www/myapp/",
instances: 2,
autorestart: true,
watch: false,
max_memory_restart: '1G',
env: {
NODE_ENV: 'development'
},
env_production: {
NODE_ENV: 'production',
API_URL: 'YOUR ENV URL',
PORT:8000
}
}]
};
package.json like so
"scripts": {
"dev": "next",
"build": "next build",
"start": "next start -p 8000"
},
...
and executed something like this
#!/bin/bash
cd /var/www/myapp/
git pull && yarn install && yarn build
cd ~/
pm2 start ecosystem.config.js --env production
Then the API_URL would be available in const API_URL = process.env.API_URL in your app.
These urls helped
https://willandskill.se/en/setup-a-next-js-project-with-pm2-nginx-and-yarn-on-ubuntu-18-04/
https://pm2.keymetrics.io/docs/usage/application-declaration/

Answer 2

Another idea would be passing all the env parameters of PM2 to the server via the following.
ecosystem.config.js being:
module.exports = {
apps: [{
name: "my-service-1",
script: "dist/server.js",
env_production: process.env, // pass all the env params of the container to node
}],
};

Answer 3

#webface
The environment variables in your example will not be available in Nextjs. To be available to both the client and server, variables must be prefixed with NEXT_PUBLIC (ie. NEXT_PUBLIC_API_VERSION).
These environment variables must be passed into the build process to be available at runtime.