Docker Engine Discrepancy with Docker Compose Secrets

This repository shows a mismatch of how Docker Secrets set via Environment Variable:

Works with Docker Engine v23.x with most Docker Compose v2 plugins

DOES not work with Docker Engine v24.x with most Docker Compose v2 plugins

This repository is meant to address Docker Compose Issue 10663.

Environment

Host Machine

NAME="Manjaro Linux"
PRETTY_NAME="Manjaro Linux"
ID=manjaro
ID_LIKE=arch
BUILD_ID=rolling
ANSI_COLOR="32;1;24;144;200"
HOME_URL="https://manjaro.org/"
DOCUMENTATION_URL="https://wiki.manjaro.org/"
SUPPORT_URL="https://forum.manjaro.org/"
BUG_REPORT_URL="https://docs.manjaro.org/reporting-bugs/"
PRIVACY_POLICY_URL="https://manjaro.org/privacy-policy/"
LOGO=manjarolinux

Vagrant Version

used to spin up isolated Environments (VMs) using Virtual Box

Installed Version: 2.3.4

Virtual Box version:

7.0.8 r156879

Ansible Version

used to provision Vagrant Boxes with Docker Engine / Docker Compose software

ansible [core 2.15.0]

Setup

In both Vagrant boxes we will install the following Docker Compose versions:

Compose Version	Binary in Vagrant Box
v2.16.0	docker-compose-v2.16.0
v2.17.3	docker-compose-v2.17.3
v2.18.1	docker-compose-v2.18.1

Docker Engine v23.x

Software	Version
containerd.io	1.6.9
docker-ce-cli	23.0.6
docker-ce	23.0.6
docker-buildx-plugin	0.10.4

Docker Engine v24.x

Software	Version
containerd.io	1.6.21
docker-ce-cli	24.0.2
docker-ce	24.0.2
docker-buildx-plugin	0.10.4

Steps

Docker Engine v23.x

1. Bring the Box up and log in:

   $ cd engine-v23
   $ vagrant up
   $ vagrant ssh

2. In the box:

   $ cd /vagrant
   $ FOO=hello docker-compose-v2.16.0 run demo cat /run/secrets/foo
   $ FOO=hello docker-compose-v2.17.3 run demo cat /run/secrets/foo
   $ FOO=hello docker-compose-v2.18.1 run demo cat /run/secrets/foo

Docker Engine v24.x

1. Bring the Box up and log in:

   $ cd engine-v24
   $ vagrant up
   $ vagrant ssh

2. In the box:

   $ cd /vagrant
   $ FOO=hello docker-compose-v2.16.0 run demo cat /run/secrets/foo
   $ FOO=hello docker-compose-v2.17.3 run demo cat /run/secrets/foo
   $ FOO=hello docker-compose-v2.18.1 run demo cat /run/secrets/foo

Results

Docker Engine v23.x

Docker Engine v24.x