superset/docker/README.md

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# Getting Started with Superset using Docker

Docker is an easy way to get started with Superset.

## Prerequisites

1. [Docker](https://www.docker.com/get-started)
2. [Docker Compose](https://docs.docker.com/compose/install/)

## Configuration

The `/app/pythonpath` folder is mounted from [`./docker/pythonpath_dev`](./pythonpath_dev)
which contains a base configuration [`./docker/pythonpath_dev/superset_config.py`](./pythonpath_dev/superset_config.py)
intended for use with local development.

### Local overrides

In order to override configuration settings locally, simply make a copy of [`./docker/pythonpath_dev/superset_config_local.example`](./pythonpath_dev/superset_config_local.example)
into `./docker/pythonpath_dev/superset_config_docker.py` (git ignored) and fill in your overrides.

### Local packages

If you want to add Python packages in order to test things like databases locally, you can simply add a local requirements.txt (`./docker/requirements-local.txt`)
and rebuild your Docker stack.

Steps:

1. Create `./docker/requirements-local.txt`
2. Add your new packages
3. Rebuild docker compose
    1. `docker compose down -v`
    2. `docker compose up`

## Initializing Database

The database will initialize itself upon startup via the init container ([`superset-init`](./docker-init.sh)). This may take a minute.

## Normal Operation

To run the container, simply run: `docker compose up`

After waiting several minutes for Superset initialization to finish, you can open a browser and view [`http://localhost:8088`](http://localhost:8088)
to start your journey.

## Developing

While running, the container server will reload on modification of the Superset Python and JavaScript source code.
Don't forget to reload the page to take the new frontend into account though.

## Production

It is possible to run Superset in non-development mode by using [`docker-compose-non-dev.yml`](../docker-compose-non-dev.yml). This file excludes the volumes needed for development and uses [`./docker/.env-non-dev`](./.env-non-dev) which sets the variable `SUPERSET_ENV` to `production`.

## Resource Constraints

If you are attempting to build on macOS and it exits with 137 you need to increase your Docker resources. See instructions [here](https://docs.docker.com/docker-for-mac/#advanced) (search for memory)