Database access error on self hosted nextjs docker container

[hdesma]

Summary

Hello
As part of teaching myself nextjs, I wrote a small roster app for a group I help manage. It's mostly mugshot + name and title.
Those are stored in a small better-sqlite3 db located at the root of my project, and accessed when needed through functions stored in a library file.
This works well enough in local (including running the actual docker image), but upon deploying a container image on my self hosted nginx server, I'm getting this on accessing the app:

⨯ TypeError: Cannot read properties of undefined (reading 'id') at h (.next/server/chunks/ssr/_39c43809._.js:12:591) { digest: '2257150320' }
I am
From some cursory research I've done, I'm led to thinking that it may be due to the nature of a sqlite db and how it works with a docker container. Is there something I either need to do add in my dockerfile, or do I need to switch to a different type of db altogether?
Thanks in advance.

Additional information

No response

Example

No response

[icyJoseph]

Do you have verbose logging, and are you able to navigate the deployed image through sh?

When you say it works locally, do you also mean next build + start?

How do you connect to the DB? Is the path correct? You might have to use process.env.cwd() and join it to the path you expect the DB to be at.

[Toygarmetu]

This is a very common issue with SQLite + Docker! The problem is almost certainly the database file path.

When running locally, your SQLite db resolves relative to your project root. Inside a Docker container, the working directory and filesystem are different — so better-sqlite3 cannot find the file at the expected path.

Fix 1: Use an absolute path with a volume mount (recommended)

In your docker-compose, mount a volume:

volumes:
  - ./data/roster.db:/app/data/roster.db

Then in your code:

import Database from 'better-sqlite3';
import path from 'path';

const db = new Database(path.join(process.cwd(), 'data', 'roster.db'));

Fix 2: Use an environment variable for the path

const db = new Database(process.env.DB_PATH || path.join(process.cwd(), 'roster.db'));

Then pass DB_PATH=/app/data/roster.db in your Docker environment.

Why the error looks unrelated: Next.js catches the DB init failure silently and the crash surfaces later when code tries to use the undefined result — hence the confusing Cannot read properties of undefined (reading 'id') message.

You do NOT need to switch databases — SQLite works perfectly fine in Docker as long as the file path is correct and persisted via a volume.