Error with `DOCKER_CONTENT_TRUST=1`

[mindflayer]

I've just added this GitHub Action to our deployment one and if fails with the following error:

Run rtCamp/action-slack-notify@v2
/usr/bin/docker run --name ghcriortcampactionslacknotifyv220_412134 --label 3bec5f --workdir /github/workspace --rm -e DOCKER_CONTENT_TRUST -e SLACK_CHANNEL -e SLACK_COLOR -e SLACK_ICON -e SLACK_TITLE -e SLACK_MESSAGE -e SLACK_USERNAME -e SLACK_WEBHOOK -e HOME -e GITHUB_JOB -e GITHUB_REF -e GITHUB_SHA -e GITHUB_REPOSITORY -e GITHUB_REPOSITORY_OWNER -e GITHUB_RUN_ID -e GITHUB_RUN_NUMBER -e GITHUB_RETENTION_DAYS -e GITHUB_ACTOR -e GITHUB_WORKFLOW -e GITHUB_HEAD_REF -e GITHUB_BASE_REF -e GITHUB_EVENT_NAME -e GITHUB_SERVER_URL -e GITHUB_API_URL -e GITHUB_GRAPHQL_URL -e GITHUB_WORKSPACE -e GITHUB_ACTION -e GITHUB_EVENT_PATH -e GITHUB_ACTION_REPOSITORY -e GITHUB_ACTION_REF -e GITHUB_PATH -e GITHUB_ENV -e RUNNER_OS -e RUNNER_TOOL_CACHE -e RUNNER_TEMP -e RUNNER_WORKSPACE -e ACTIONS_RUNTIME_URL -e ACTIONS_RUNTIME_TOKEN -e ACTIONS_CACHE_URL -e GITHUB_ACTIONS=true -e CI=true -v "/var/run/docker.sock":"/var/run/docker.sock" -v "/home/runner/work/_temp/_github_home":"/github/home" -v "/home/runner/work/_temp/_github_workflow":"/github/workflow" -v "/home/runner/work/_temp/_runner_file_commands":"/github/file_commands" -v "/home/runner/work/<project-dir>":"/github/workspace" ghcr.io/rtcamp/action-slack-notify:v2.2.0
docker: error establishing connection to trust repository: mkdir /github: permission denied.
See 'docker run --help'.

I suspect it has to do with the content trust check which we enabled for security purposes: https://docs.docker.com/engine/security/trust/.

[mindflayer]

I am trying to fix it adding DOCKER_CONTENT_TRUST: 0 to the env for the specific step.

[mindflayer]

It worked, but I leave this issue opened so you'll decide if and how to proceed.

[mrrobot47]

Content trust is disabled by default in the Docker Client. As of now our image is not signed.
We may look into signing it in the future. cc @dhsathiya