This script allows to delete old gitlab pipelines that still use disk space for the artifacts, build logs and so on

gitlab-delete-old-pipelines.sh

#!/bin/bash

#
# This script allows to delete old gitlab pipelines that still use disk space for the artifacts, build logs and so on.
# It will keep the last 100 pipelines. Make sure to modify your PRIVATE_TOKEN, your PROJECT_ID and your GITLAB_URL.
#
# If you want to run the script in dry mode - set _dryrun to 1 - it won't delete anything in that case, but just you the
# pipeline ids it would delete
#
# Used in combination with https://github.com/K-MailOrder/gitlab-migration to reduce the size of a gitlab instance
# before doing the migration.
#
# License: WTFPL
#

set -euo pipefail

# Replace these variables with your GitLab credentials and project details
GITLAB_URL="https://gitlab.xxx.com"
PRIVATE_TOKEN="YOURTOKEN"
# your gitlab project id to get the pipelines from
PROJECT_ID="1"
# keep this amount of pipelines - can't be 0 and must be smaller or equal to 100
KEEP="100"

##
## Internal vars
##

_dryrun=0
# start from this page on to delete the pipelines - keep anything that is on page 1
# note: if you set this higher, you will keep (_page-1)*KEEP pipelines.
_page=2

while true; do
    # Get a list of all pipelines for the project
    pipelines=$(curl -s --header "PRIVATE-TOKEN: $PRIVATE_TOKEN" "$GITLAB_URL/api/v4/projects/$PROJECT_ID/pipelines?page=${_page}&per_page=$KEEP")

    # Check if pipelines is empty
    if [ "$(echo "$pipelines" | jq '. | length')" -eq 0 ]; then
        echo "No pipelines found. Exiting..."
        break
    fi

    # Loop through each pipeline and delete it
    for pipeline_id in $(echo "$pipelines" | jq -r '.[].id' | sort -n); do
        echo -n "Deleting pipeline $pipeline_id... "
        if [ ${_dryrun} -eq 1 ]; then
            echo " [dryrun]"
        else
            response=$(curl -s --write-out "%{http_code}" --output /dev/null --request DELETE --header "PRIVATE-TOKEN: $PRIVATE_TOKEN" "$GITLAB_URL/api/v4/projects/$PROJECT_ID/pipelines/$pipeline_id")
            if [ "$response" -eq 204 ]; then
                echo " [done]"
            else
                echo " [failed]"
                exit 1
            fi
        fi
    done

    # advance here only - as the script would not end otherwise
    if [ ${_dryrun} -eq 1 ]; then
        ((_page++))
    fi
done

echo "All pipelines deleted successfully - kept $KEEP pipelines."