Testing

Dalec supports adding tests to your spec file. These tests are run against the container produced by your spec. Dalec provides a few test helpers to make it easier to write tests when your image doesn't have the tools you need.

Checks for files

Check file existence

name: My Package
# ... other spec fields

tests:
    -
        name: My Test case
        files:
            /usr/bin/foo:

Check file contents

Here are some examples on how to check the contents and metadata of a file in the output container. You can use these to check that the files you expect are present and have the correct contents.

Check that a file contains some value:

Here we check that the content of the file /etc/foo.conf contains the string foo=bar. You can specify multiple values to check for.

name: My Package
# ... other spec fields

tests:
    -
        name: My Test case
        files:
            /etc/foo.conf:
                contains:
                    - foo=bar

Check that a file starts with some value:

Here we check that the content of the file /etc/foo.conf starts with the string foo.

name: My Package
# ... other spec fields

tests:
    -
        name: My Test case
        files:
            /etc/foo.conf:
                starts_with: foo

Check that a file ends with some value:

Here we check that the content of the file /etc/foo.conf ends with the string bar.

name: My Package
# ... other spec fields

tests:
    -
        name: My Test case
        files:
            /etc/foo.conf:
                ends_with: bar

Check that a file matches a regular expression:

Here we check that the content of the file /etc/foo.conf matches the regular expression foo=.*.

name: My Package
# ... other spec fields

tests:
    -
        name: My Test case
        files:
            /etc/foo.conf:
                matches: "foo=.*"

Check that a file does not exist

Here we check that the file /some/nonexistent/path does not exist.

name: My Package
# ... other spec fields

tests:
    -
        name: My Test case
        files:
            /some/nonexistent/path:
                not_exist: true

Check that a path is a directory

Here we check that the path /some/path is a directory.

name: My Package
# ... other spec fields

tests:
    -
        name: My Test case
        files:
            /some/path:
                is_dir: true

Check file permissions

Here we check that the file /etc/foo.conf has the permissions 0644.

name: My Package
# ... other spec fields

tests:
    -
        name: My Test case
        files:
            /etc/foo.conf:
                permissions: 0644

Add multiple checks together

You can add multiple checks together to check multiple things about a file. Note that some checks are mutually exclusive and will cause an error if you try to use them together.

name: My Package
# ... other spec fields

tests:
    -
        name: My Test case
        files:
            /etc/foo.conf:
                contains:
                    - foo=bar
                starts_with: foo
                ends_with: bar
                matches: "foo=.*"
                permissions: 0644

Run a command

You can run a command in the container and check the stdout and/or stderr of that command. These commands are run before any of the file checks are run and may influence the output of those checks.

Because these images often will not have a shell in them, if you want a shell you'll need to run it explicitly.

Capture stdio streams

name: My Package
# ... other spec fields

tests:
    -
        name: My Test case
        steps:
            -
                command: echo "hello world"
                stdout:
                    equals:
                        - hello world\n
            -
                # Note: the image used for this test would need to have a shell in it for this to work
                command: /bin/sh -c 'echo "hello world" >&2'
                stderr:
                    equals:
                        - hello world\n

Pass in stdin to the command:

name: My Package
# ... other spec fields

tests:
    -
        name: My Test case
        steps:
            -
                command: cat
                stdin: hello world
                stdout:
                    equals:
                        - hello world

Inject a file into the container for additional checks

Test cases support source mounts just like in the main spec. You can use this to inject files, build helper binaries, or add whatever you need to run a test.

name: My Package
# ... other spec fields

tests:
    -
        name: My Test case
        mounts:
            -
                dest: /target/mount/path
                spec:
                    build:
                        source:
                            inline:
                                file:
                                    contents: |
                                        FROM busybox
                                        RUN echo hello > /hello

                                        FROM scratch
                                        COPY --from=busybox /hello /hello
        steps:
            -
                command: cat /path/in/container
                stdout:
                    equals: hello