For logging, I generally use Elasticsearch to store the logs themselves, and Kibana for visualizing said logs.

Naturally, I use the software via Docker.

Unlike most Docker images, Elasticsearch and Kibana do not have a rolling latest tag. This means you must request a specific image to run a container. The supported images are listed on the page.

dockerImages

The problem is knowing when there are new builds of the images.

One way is to periodically check the Docker Hub page.

Another is to use the command console to check for yourself.

You can make use of the following endpoint for this purpose:

http "https://registry.hub.docker.com/v2/repositories/library/<image-name>/tags/"

So, for this case we do the following using Httpie

http  "https://registry.hub.docker.com/v2/repositories/library/elasticsearch/tags/"

This returns a large JSON object

dockerJSON

We need only to fetch the interesting bits:

dockerTag

We can extract this tag that is in the name property from the results array using the jq tool, like this:

http "https://registry.hub.docker.com/v2/repositories/library/elasticsearch/tags/" | jq -r '.results[].name'

This returns the following:

8.17.2
8.16.4
8.17.1
8.16.3
7.17.27
8.17.0
8.16.2
7.17.26
8.15.5
8.16.1

Much less noisy, but needs to be sorted.

We can pipe this to the sort command and specify that we want a reverse sort. Like so:

http "https://registry.hub.docker.com/v2/repositories/library/elasticsearch/tags/" | jq -r '.results[].name' | sort -r

This returns the following:

8.17.2
8.17.1
8.17.0
8.16.4
8.16.3
8.16.2
8.16.1
8.15.5
7.17.27
7.17.26

Is there a simpler way? Probably. I’d be interested in hearing from you. My email is on the about page.

Happy hacking!