BATS: Add test for volume mounts

This creates an initial test for volume mounts, mostly to figure out the
correct behaviour around file ownership.

Signed-off-by: Mark Yen <[email protected]>

Author: mook-as

bats/tests/containers/volumes.bats

@@ -0,0 +1,144 @@
+load '../helpers/load'
+
+get_tempdir() {
+    if ! is_windows; then
+        echo "$BATS_TEST_TMPDIR"
+        return
+    fi
+    # On Windows, create a temporary directory that is in the Windows temporary
+    # directory so that it mounts correctly.  Note that in CI we end up running
+    # with PSModulePath set to pwsh (7.x) paths, and that breaks the code for
+    # PowerShell 5.1.  So we need to have alternative code in that case.
+    # See also https://github.com/PowerShell/PowerShell/issues/14100
+    if command -v pwsh.exe &>/dev/null; then
+        # shellcheck disable=SC2016 # Don't expand PowerShell expansion
+        local command='
+            $([System.IO.Directory]::CreateTempSubdirectory()).FullName
+        '
+        run pwsh.exe -Command "$command"
+        assert_success
+    else
+        # PowerShell 5.1 is built against .net Framework 4.x and doesn't have
+        # [System.IO.Directory]::CreateTempSubdirectory(); create a temporary
+        # file and use its name instead.
+        # shellcheck disable=SC2016 # Don't expand PowerShell expansion
+        local command='
+            $name = New-TemporaryFile
+            Remove-Item -Path $name
+            Start-Sleep -Seconds 1 # Allow anti-virus to do stuff
+            New-Item -Type Directory -Path $name | Out-Null
+            $name.FullName
+        '
+        run powershell.exe -Command "$command"
+        assert_success
+    fi
+    run wslpath -u "$output"
+    assert_success
+    echo "$output" | tr -d "\r"
+}
+
+local_setup() {
+    unset PSModulePath # On Windows, fix running PowerShell 5.1 within pwsh 7
+    run get_tempdir
+    assert_success
+    export WORK_PATH=$output
+}
+
+local_teardown() {
+    # Only do manual deletion on Windows; elsewhere we use BATS_TEST_TMPDIR so
+    # BATS is expected to do the cleanup.
+    if is_windows && [[ -n $WORK_PATH ]]; then
+        local host_work_path
+        host_work_path=$(host_path "$WORK_PATH")
+        powershell.exe -Command "Remove-Item -Recurse -LiteralPath '$host_work_path'"
+    fi
+}
+
+@test 'factory reset' {
+    factory_reset
+}
+
+@test 'start container engine' {
+    if is_linux; then
+        # On linux, mount BATS_RUN_TMPDIR into the VM so that we can use
+        # BATS_TEST_TMPDIR as a volume.
+        local override_dir="${HOME}/.local/share/rancher-desktop/lima/_config"
+        mkdir -p "$override_dir"
+        {
+            echo "mounts:"
+            echo "- location: ${BATS_RUN_TMPDIR}"
+            echo "  writable: true"
+        } >"$override_dir/override.yaml"
+    fi
+    start_container_engine
+    wait_for_container_engine
+}
+
+@test 'read-only volume mount' {
+    # Read a file that was created outside the container.
+    create_file "$WORK_PATH/foo" <<<hello
+    # Use `--separate-stderr` to avoid image pull messages.
+    run --separate-stderr \
+        ctrctl run --volume "$(host_path "$WORK_PATH"):/mount:ro" \
+        "$IMAGE_BUSYBOX" cat /mount/foo
+    assert_success
+    assert_output hello
+}
+
+@test 'read-write volume mount' {
+    # Create a file from the container.
+    ctrctl run --volume "$(host_path "$WORK_PATH"):/mount:rw" \
+        "$IMAGE_BUSYBOX" sh -c 'echo hello > /mount/foo'
+    # Check that the file was written to.
+    run cat "$WORK_PATH/foo"
+    assert_success
+    assert_output hello
+}
+
+@test 'read-write volume mount as user' {
+    # Create a file from within the container.
+    ctrctl run --volume "$(host_path "$WORK_PATH"):/mount:rw" \
+        --user 1000:1000 "$IMAGE_BUSYBOX" sh -c 'echo hello > /mount/foo'
+    run cat "$WORK_PATH/foo"
+    assert_success
+    assert_output hello
+    # Try to append to the file.
+    ctrctl run --volume "$(host_path "$WORK_PATH"):/mount:rw" \
+        --user 1000:1000 "$IMAGE_BUSYBOX" sh -c 'echo hello | tee -a /mount/foo'
+    # Check that the file was modified.
+    run cat "$WORK_PATH/foo"
+    assert_success
+    assert_output hello$'\n'hello
+    if is_windows && using_windows_exe; then
+        # On Windows, the directory may be owned by a group that the user is in;
+        # additionally, there isn't an easy API to get effective access (!?).
+        # shellcheck disable=SC2016 # Don't expand PowerShell expansion
+        local command='
+            $type = [System.Type]::GetType("System.Security.Principal.SecurityIdentifier")
+            $owner = $(Get-Acl '"'$host_work_path/foo'"').GetOwner($type)
+            $owner.Value
+        '
+        run powershell.exe -Command "$command"
+        assert_success
+        local owner=${output//$'\r'/}
+        # shellcheck disable=SC2016 # Don't expand PowerShell expansion
+        command='
+            $identity = [System.Security.Principal.WindowsIdentity]::GetCurrent()
+            $groups = $identity.Groups
+            $groups.Add($identity.User)
+            $groups | ForEach-Object { $_.Value }
+        '
+        run powershell.exe -Command "$command"
+        assert_success
+        assert_line "$owner"
+    else
+        # Check that the file is owned by the current user.
+        stat_arg=-f # Assume BSD stat
+        if stat --version | grep 'GNU coreutils'; then
+            stat_arg=-c
+        fi
+        run stat "$stat_arg" '%u:%g' "$WORK_PATH/foo"
+        assert_success
+        assert_output "$(id -u):$(id -g)"
+    fi
+}