Re: building a singularity image from docker hub postgres image

[Allan Kamau <kamauallan@xxxxxxxxx>]

On Tue, Jan 30, 2024 at 12:27 PM Justin Clift <justin@xxxxxxxxxxxxxx> wrote:

On 2024-01-30 15:52, Allan Kamau wrote:
> I am trying to build a singularity image from postgres docker image.
> I am issuing the command below.
>
> $ singularity build /local/data/some/postgres.16.1.sif
> docker://postgres/postgres:16.1
>
> INFO:    Starting build...
> INFO:    Fetching OCI image...
> FATAL:   While performing build: conveyor failed to get: GET
> https://index.docker.io/v2/postgres/postgres/manifests/16.1:
> UNAUTHORIZED:
> authentication required; [map[Action:pull Class: Name:postgres/postgres
> Type:repository]]
>
> What is the url I should use?

Not personally familiar with Singularity, but this post looks like it
should help:


https://www.linuxwave.info/2022/04/running-postgresql-database-using.html

The example command they have there is:

   singularity pull docker://postgres:14.2-alpine3.15

So the format of the url *seems* like it should be:

   docker://postgres:16.1

That just pure guess work though. :)

Regards and best wishes,

Justin Clift

Thanks Justin for the corrections and resources.

I have now put together the command below that does what I was looking for.

$ cd /tmp/;singularity pull postgres_16.1-alpine3.19.sif docker://postgres:16.1-alpine3.19;

I am using the singularity container for the postgresql binaries instead of having to install the binaries on the computer. For example I am using pg_dump to take backups.

This could be of help to others, below is an example of using the PostgreSQL binaries in the singularity image built from PostgreSQL docker image.

##construct the singularity image
singularity_image_dfn="/local/data/bcl-sdv/singularity/pg";
mkdir -p "${singularity_image_dfn}";
date;time singularity build "${singularity_image_dfn}"/postgres.16.1-alpine3.19.sif docker://postgres/postgres:16.1-alpine3.19;date;

##Example usage of the singularity image
date;time {
    singularity_image_fn="/local/data/bcl-sdv/singularity/pg/postgres_16.1-alpine3.19.sif";
    date;time singularity exec \
        --workdir /tmp \
        "${singularity_image_fn}" \
            "psql" \
                "postgresql://someusername:somepassword@somehostname:5423/some_db_name" \
                "-c" \
                "SELECT version();" \
    ;date;
};date;

Allan.