Superset Custom Docker Image

Apache Superset is a great open-source visualization and dashboarding tool that can be connected to a multitude of data sources. For many of those data sources, additional drivers/packages need to be installed.

But how to do that when using the default Docker-image? Also: how can we easily change superset-configurations. This is possible with a very simple custom Docker image.

1. Create a custom “Dockerfile”:

   FROM apache/superset:2.0.0
   
   USER root
   
   RUN pip install duckdb-engine
   
   COPY ./start.sh /start.sh
   
   COPY superset_config.py /app/
   ENV SUPERSET_CONFIG_PATH /app/superset_config.py
   
   USER superset
   ENTRYPOINT [ "/start.sh" ]
   

   This Dockerfile builds on top of the default Superset-image. Using the root-account, we install additional packages, here duckdb-engine because I want to connect to DuckDB (see here for other connections).

   Then we copy the start-script (see 2.) and the superset-config (see 3.) Finally, we switch back to the non-root user, as is best practice, and set the start-script as entrypoint.

2. Create a start-script start.sh. It is important that you make this file executable with chmod +x start.sh.

   #!/bin/bash
   
   superset fab create-admin --username admin --firstname Superset --lastname Admin --email admin@superset.com --password "admin"
   
   superset db upgrade
   
   superset init
   
   echo "Starting server"
   /bin/sh -c /usr/bin/run-server.sh
   

   This script creates an admin user “admin” with password “admin” (change accordingly and add other users with superset fab create-user). Then the database is upgraded and initialized. Finally the server is started.

   This script can also be used to create roles at start-up.

3. Create a superset-config-file superset_config.py. Find here the original config-file from where you can get an idea of which configs can be set and modified.

   FEATURE_FLAGS = {
       "ENABLE_TEMPLATE_PROCESSING": True,
   }
   
   def square(x):
       return x**2
   
   JINJA_CONTEXT_ADDONS = {
       'my_crazy_macro': square
   }
   

   This config is just an example. As you can see, this file can also be used to define functions that can be used as jinja-templates in the SQL-editor.

   Also, we can define custom auth here (article to follow).

4. Build the Docker-image with docker build -f Dockerfile -t superset . and run with docker run -p 8088:8088 superset.