Generate standalone output of your Next.js app and deploy through pm2

References

https://nextjs.org/docs/pages/api-reference/config/next-config-js/output

Set Next.js to output standalone

// next.config.mjs located in the same directory as package.json

// *** START: Export a DEFAULT object, i.e nextConfig
const nextConfig = {}

// Produce standalone output
// ---------------------------------
//  "next start" doesn't generate standalone output.
//  Generate standalone output if BUILD_STANDALONE=true.
nextConfig.output = process.env.BUILD_STANDALONE === "true" ? "standalone" : undefined;

// *** END: Export
export default nextConfig;

Build & deploy

Run build to generate standalone directory

export BUILD_STANDALONE=true
npm run build

#\cp -a data         .next/standalone/  # For other file. e.g. myDb.sqlite
\cp -a public       .next/standalone/
\cp -a .next/static .next/standalone/.next/

Run

nextjs_port=4666
export PORT=${nextjs_port}
node .next/standalone/server.js

Or, deploy using pm2

nextjs_app_name="openwritings.net"
nextjs_port=4666

# Remove entry if it already exists.
pm2 stop ${nextjs_app_name} || true
pm2 delete ${nextjs_app_name} || true

# Run & deploy using pm2
export PORT=${nextjs_port}
pm2 start node --name ${nextjs_app_name} -- .next/standalone/server.js

# Save it so after computer reboot, it will automatically run.
pm2 save

Ignore .next/standalone directory

Ignore thousands of files in .next/standalone directory.

# Doesn´t work.
git rm -r --cached .next/standalone
git commit -m "Ignore Next.js standalone output"
git push

// ~/.config/Code/User/settings.json
{
    "files.exclude": {
        "**/.next/standalone": true
    },
    "search.exclude": {
        "**/.next/standalone": true
    }
}

Issues

Error such as "File not found" or "Sqlite database file not found".
- This is likely you pass a full path or a relative path where your file is not found under ./standalone/ directory.
- The solution that I'm proposing is:
  - For all your file paths, use relative path to the ROOT directory of your Next.js app.(<Next_ROOT_DIR>/package.json)
  - ./standalone/ directory becomes the <Next_ROOT_DIR> directory.
  - Therefore, copy your files under ./standalone/ directory.
  - Example: my ./data/ is copied to ./standalone/
```
data/
├── _empty_db.txt
├── rampricesdeal.db
└── _readme.sh
package.json

#...

.next/standalone/data
                ├── _empty_db.txt
                ├── rampricesdeal.db
                └── _readme.sh
```