Create a Singularity container from a Docker pull

There are multiple ways how to create a Singularity container.

This page shows how to create a Singularity container from a Docker pull, such as this one (from here)

docker pull lycheeverse/lychee

Procedure

Prefer a video?

You can see the procedure below in the video Create a Singularity container from docker pull.

The hardest part of this procedure may be to have Linux with Singularity installed on a computer where you have super-user rights.

In this example, we create a Singularity container for lychee, a tool to check for broken links in text files.

1. Create the Singularity container

Here we build a Singularity container from a Docker file:

sudo singularity build my_container.sif [location to Docker file]

The magic is in [location to Docker file].

In our case, we have seen the documentation state the command docker pull lycheeverse/lychee to install this Docker container. Using a docker pull like this, means that the Docker script is on Docker Hub. And yes, our Docker script is on Docker Hub!

To build a Singularity container from a Docker file on Docker Hub, do:

sudo singularity build my_container.sif docker:lycheeverse/lychee

2. Use the Singularity container

./my_container.sif [your command-line arguments]

For example, in this case:

./my_container.sif .

The . means 'in this folder'.

As, in this example, we have created a Singularity container for lychee, a tool to check for broken links in text files. Hence, the full command can be read as 'Check all files in this folder for broken links'.