Manifest.yml

A Skill's `manifest.yml` file is the default method for defining the dependencies of a Mycroft Skill.

In this file we can include Python packages, Linux applications or other Mycroft skills that are required for our own Skill to function properly.

YAML is a language commonly used for configuration files. It uses indentation rather than brackets or parentheses to define the structure or hierarchy of its contents.

File contents

We start the manifest.yml by defining a top-level key of dependencies and the type of dependency we want to include.

dependencies:
  python:

Python Packages

Here we can see a simple example that defines the requests and gensim Python packages as required dependencies.

dependencies:
  python:
    - requests
    - gensim

When a Skill with this manifest.yml file is being installed, Mycroft would check for, and if required install, both packages from PyPI using the PIP installer.

There is no limit to the number of packages you can install, however these are reviewed during the Skills Acceptance Process to ensure they are appropriate for the Skill being installed.

Linux System Packages

Linux packages are defined under the system key. As Mycroft can be installed on many different Linux distributions, support is provided for a range of package managers.

For packages that have consistent naming across package managers, we can use all.

dependencies:
  system:
    all: pianobar piano-dev

If the package has a different name on specific platforms, we can define that using the name of the package manager as a key. In the following example, we want to use the libpiano-dev package when using the APT package manager on Debian, Ubuntu and other related distributions.

dependencies:
  system:
    all: pianobar piano-dev
    apt-get: pianobar libpiano-dev

Finally we can check that certain executables are available for the install to succeed. This is done by checking the PATH environment variable.

dependencies:
  system:
    all: pianobar piano-dev
    apt-get: pianobar libpiano-dev  

  exes:
    - pianobar

Here we have installed a number of pianobar packages, and then verify that the pianobar executable is available for our Skill.

Other Mycroft Skills

A Skill may even require that other Mycroft Skills are installed rather than duplicate functionality. Here we can see that the Cocktails Skill and the Mozilla Webthings Gateway are listed as dependencies.

dependencies:
  skill:
    - cocktails
    - webthings-gateway

Anything listed in this section will be passed to the Mycroft Skills Manager for installation. A feature of MSM is that it will search for Skills that most closely match the given string. So even though the mozilla-webthings-gateway Skill has not been perfectly entered, it will still match with a high enough confidence to install the Skill.

Example files

A complete manifest.yml example can be found in the official Template Skill on Github.

A simple example from a real Skill can be found in the Desktop Launcher Skill.