Litestream + PocketBase Example

This repository provides an example of running PocketBase in the same container as Litestream. It's a fork of the Litestream & Docker example here: https://github.com/benbjohnson/litestream-docker-example

PocketBase is a Go web backend that provides APIs similar to Firebase (realtime subscriptions). It uses sqlite as its database and provides an Admin web interface for creating data models and viewing and modifying the data. This is pretty nifty because, similar to Firebase, one can build some types of apps without needing to write any backend code.

Litestream provides live replication of sqlite to S3 (as well as other storage services). It has a subprocess execution mode that makes it easier to run a web app and the Litestream replication process together in a single container.

Putting these two things together, you get a web backend that runs as a single container, with data continuously backed up to S3 (which is pretty cheap for small amounts of data). The container does not need to have persistent storage mounted as a volume. The configuration of data models can be done in a web interface. The single container approach works well with services like Fly.io, where running one container on a small compute instance is free. And to top it all off, this setup has minimal lock-in. The data is in sqlite, it's possible to use other storage services than S3, and the PocketBase Go application is open source and can be extended.

The main drawbacks are that only one instance of the application can be running and the data must be relatively small. Both issues could potentially be addressed by sharding the data. In addition, Litestream is planned to add support for live read replicas, which would allow multiple instances of the app to work on the same data. It might also be possible to go pretty far with vertical scaling, i. e., use compute instances with a lot of CPU and memory.

Usage

Prerequisites

It's assumed you have an AWS account and have created an IAM user with permissions for an S3 bucket called pocketbase-litestream-demo.

You'll need to get an access key id and secret for the IAM user and set them in your shell environment:

export LITESTREAM_ACCESS_KEY_ID=XXX
export LITESTREAM_SECRET_ACCESS_KEY=XXX

Building & running the container

You can build the application with the following command:

docker build -t pocketbase-litestream-demo .

Once the image is built, you can run it with the following command. Assumes that you have a bucket called pocketbase-litestream-demo.

docker run -i -t \
  -p 8090:8090 \
  -e REPLICA_URL=s3://pocketbase-litestream-demo/pb_data \
  -e LITESTREAM_ACCESS_KEY_ID \
  -e LITESTREAM_SECRET_ACCESS_KEY \
  pocketbase-litestream-demo

Testing it out

Go ahead and follow the link PocketBase prints to the terminal to open the admin UI. Create an admin user.

Now, create a collection, add a field to it, and create a few records.

Try stopping the container and start it again. If you refresh the admin page, you should remain logged in and continue to see the records you just created.

Downloading the database

You can download a copy of the database, if, for example, you wanted to inspect it locally or port the data to another web application/framework:

litestream restore -o data.db s3://pocketbase-litestream-demo/pb_data