Run Docker Compose integration tests - Microsandbox

Run Docker Compose inside a microVM when a test needs several containers. The inner daemon gets its own disk and never receives the host's /var/run/docker.sock.

This example assumes the current directory contains compose.yaml and a test service named test.

Run the integration tests

<Tooltip tip="On microsandbox cloud, create a directory-backed Docker volume first and omit disk-kind, size, and replace-on-create options from this command."><span className="msb-badge-limited">Limited on cloud <Icon icon="circle-info" size={11} /></span></Tooltip>

<CodeGroup> ```sh macOS & Linux msb run -d --name compose-ci --replace \ --memory 2G --root-disk 4G --max-duration 10m \ --mount-named compose-ci-cache:/var/lib/docker:kind=disk,size=6G \ --copy-dir .:/workspace --workdir /workspace \ docker:27.5.1-dind ```

powershell

msb run -d --name compose-ci --replace `
  --memory 2G --root-disk 4G --max-duration 10m `
  --mount-named compose-ci-cache:/var/lib/docker:kind=disk,size=6G `
  --copy-dir .:/workspace --workdir /workspace `
  docker:27.5.1-dind

</CodeGroup>

The official dind image starts dockerd. Wait for it before sending Compose commands:

<CodeGroup> ```sh macOS & Linux for attempt in $(seq 1 60); do msb exec compose-ci -- docker info >/dev/null 2>&1 && break sleep 1 done msb exec compose-ci -- docker info >/dev/null ```

powershell

for ($attempt = 1; $attempt -le 60; $attempt++) {
  msb exec compose-ci -- docker info *> $null
  if ($LASTEXITCODE -eq 0) { break }
  Start-Sleep -Seconds 1
}
msb exec compose-ci -- docker info *> $null
if ($LASTEXITCODE -ne 0) { throw 'Docker did not become ready' }

</CodeGroup> </Step> <Step title="Run the tests"> <CodeGroup> ```sh macOS & Linux msb exec --timeout 5m --workdir /workspace compose-ci -- \ docker compose up --build \ --abort-on-container-exit \ --exit-code-from test ```

powershell

msb exec --timeout 5m --workdir /workspace compose-ci -- `
  docker compose up --build `
    --abort-on-container-exit `
    --exit-code-from test

</CodeGroup>

Replace test with the service whose exit code should decide the CI result. msb exec returns that code to the host.

<Note> `--copy-dir` makes a guest copy. Run the command from a clean project directory, or replace it with narrower `--copy-file` and `--copy-dir` flags when the checkout contains credentials or unrelated files. </Note> </Step> <Step title="Clean up">

Stop the Compose stack inside the sandbox:

msb exec --workdir /workspace compose-ci -- docker compose down --volumes

Remove the sandbox:

msb rm -f compose-ci

Delete the cache only when you no longer need it:

msb volume remove compose-ci-cache

Keep the named volume if you want a repository-specific image cache between trusted runs. Do not share a writable cache across repositories or trust boundaries.

</Step> </Steps> <Warning> Never mount the host Docker socket into the sandbox. Control of that socket is normally control of the host Docker daemon and defeats the microVM boundary. </Warning>