How to list docker tags with date?

Question

I need a list of all repository tags for a remote Docker registry, along with their date = the date the image tag was pushed.

Or at least the tags sorted according when they were created (without the date, but in chronological order).

What I have now (from the Official Docker docs) is:

curl -XGET -u my_user:my_pass 'https://my_registry.com/v2/my_repo/tags/list'

But that seems to return the tags in random order. I need to further filter / postprocess the tags programmatically, so I need to fetch additional per-tag metadata.

Any idea how to do that?

Answer 1

My two cents:

order_tags_by_date() {
    if [ -z $1 ] || [ -z $2 ]; then
        echo "Get tag list of a component and order by date. Please enter a component name and a tag "
        echo "For example: tags my-app 20200606"
        return 1
    fi
    # get all tags list
    url=some_host
    result=$(curl -s $url:5000/v2/$1/tags/list)
    # parse page and get "tags" array, sort by name, reverse, and get as a tab separated values; 
    # separate with space and put into an array in bash; 
    # "reverse" to get the latest tag first; if you want old tag first, remove it
    IFS=" " read -r -a tags <<< "$(echo $result | jq -r '.tags | sort | reverse | @tsv')"

    # for each tag, get the same component in docker api the manifest, 
    # parse the created field by the first element in history; I assume all histories has the same created timestamp
    json="["
    for tag in $tags
    do
        host=another-docker-api-host
        date=$(curl -sk $host/v2/$1/manifests/$tag | jq -r ".history[0].v1Compatibility" | jq ".created")
        json+='{"tag":"'$tag'", "date":'$date"},"
    done;
    valid_json=${json::-1}']'
    echo $valid_json | jq 'sort_by(.date, .tag) | reverse'
}

I constructed another JSON for jq to sort on the date, tag field; because in my case, some image has timestamp based tags, but creation date is always 19700101; while other images have correct date but tags are number based; so I order by both. You can also remove "reverse" at the end to sort asc.

If you don't want the date, add this on the last line of the script, after reverse:

| .[] | .tag

So it will get all elements' tag value and they are already sorted.

jib created images, though, will have date of 1970-01-01, this is by design.

Answer 2

In the past, I wrote a script to migrate images from local docker registry to ECR, maybe you want to use some of the lines like,

tags=$(curl -s https://$username:$password@$privreg/v2/$repo/tags/list?n=2048 | jq '.tags[]' | tr -d '"')

creationdate=$(curl -s https://$username:$password@$privreg/v2/$repo/manifests/$tag | jq -r '.history[].v1Compatibility' | jq '.created' | sort | tail -n1)

#!/bin/bash
read -p 'Username: ' username
read -sp 'Password: ' password
privreg="privreg.example.com"
awsreg="<account_id>.dkr.ecr.<region_code>.amazonaws.com"
repos=$(curl -s https://$username:$password@$privreg/v2/_catalog?n=2048 | jq '.repositories[]' | tr -d '"')
for repo in $repos; do
    tags=$(curl -s https://$username:$password@$privreg/v2/$repo/tags/list?n=2048 | jq '.tags[]' | tr -d '"')
    project=${repo%/*}
    service=${repo#*/}
    awsrepo=$(aws ecr describe-repositories | grep -o \"$repo\" | tr -d '"')
    if [ "$awsrepo" != "$repo" ]; then aws ecr create-repository --repository-name $repo; fi
        for tag in $tags; do
            creationdate=$(curl -s https://$username:$password@$privreg/v2/$repo/manifests/$tag | jq -r '.history[].v1Compatibility' | jq '.created' | sort | tail -n1)
            echo "$repo:$tag      $creationdate" >> $project-$service.txt
        done
        sort -k2 $project-$service.txt | tail -n3 | cut -d " " -f1  > $project-$service-new.txt
            cat $project-$service-new.txt
        while read repoandtags; do
           sudo docker pull $privreg/$repoandtags
               sudo docker tag  $privreg/$repoandtags $awsreg/$repoandtags
               sudo docker push $awsreg/$repoandtags
        done < $project-$service-new.txt

Script might not work and need some changes, but you can use some parts of it, so I will leave it in the post as an example.