# Docker images

The docker command is used to build Docker images. By default, 3 types of images are supported:

• web - Next.js app server. (Exposes the app on port 3000).
• worker - Background worker server.
• all - Next.js app server + background worker server combined. (Exposes the Next.js app on port 3000).

The images internally bundle the QuickDapp CLI so that the actual entrypoint for each image is the prod command. This means the servers are spawned as child processes of the main process. If any server crashes then the main process (and thus the Docker container) will also crash and exit.

Images are based on Alpine Linux and are built to hold only the minimal required dependencies to run the servers. Thus, even the all image comes to <500 MB in size.

To make this possible, Webpack is used to build the background worker process to a single file. For the Next.js app the standalone option is enabled in the config.

One built the images can be run locally and/or deployed to any Docker container hosting environment of your choice.

At present, QuickDapp provides built-in support for deploying to DigitalOcean.

Most Node packages will get automatically bundled into the built output by webpack. However, some packages will still require their node_modules sub-folders to exist at runtime in order to work properly (e.g Prisma).

These can be seen inside the Dockerfile, e.g:

COPY --from=build_base /app/node_modules/.prisma ./node_modules/.prisma
COPY --from=build_base /app/node_modules/prisma ./node_modules/prisma
COPY --from=build_base /app/node_modules/@prisma ./node_modules/@prisma

If you are using a package also has the same requirement then simply add a corresponding line for it in all of the sections in the Dockerfile. For example, if you you are using the mailgen package then you would add a single line for each of the three build image types:

# web
FROM build_base as build_base_web
...
COPY --from=build_base /app/node_modules/mailgen ./node_modules/mailgen

# worker
FROM build_base as build_base_worker
...
COPY --from=build_base /app/node_modules/mailgen ./node_modules/mailgen

# web + worker combined
FROM base AS all
...
COPY --from=build_base /app/node_modules/mailgen ./node_modules/mailgen

Some NPM packages need to bundled