NAME¶

PODMAN-PILOT(8) -

NAME¶

podman-pilot - Launcher for flake applications

DESCRIPTION¶

A flake application is an application which gets called through a runtime engine. podman-pilot supports OCI containers called through the podman container engine.

podman-pilot provides the application launcher binary and is not expected to be called by users. Instead it is being used as the symlink target at the time an application is registered via flake-ctl podman register.

This means podman-pilot is the actual binary called with any application registration. If the registered application is requested as /usr/bin/myapp there will be a symlink pointing to:

/usr/bin/myapp -> /usr/bin/podman-pilot

Consequently calling myapp will effectively call podman-pilot. podman-pilot now reads the calling program basename, which is myapp and looks up all the registration metadata stored in /usr/share/flakes

Below /usr/share/flakes each application is registered with the following layout:

/usr/share/flakes/


    ├── myapp.d


    │   └── other.yaml


    └── myapp.yaml

All metadata information read by podman-pilot uses the YAML markup. The main configuration myapp.yaml is read first and can be optionally extended with further *.yaml files below the myapp.d directory. All files in the myapp.d directory will be read in alpha sort order. Redundant information will always overwrite the former one. Thus the last setting in the sequence wins.

From a content perspective the following registration parameters can be set for the supported container engine:

container:


  # Mandatory registration setup


  # Name of the container in the local registry


  name: name


  # Path of the program to call inside of the container (target)


  target_app_path: path/to/program/in/container


  # Path of the program to register on the host


  host_app_path: path/to/program/on/host


  # Optional base container to use with a delta 'container: name'


  # If specified the given 'container: name' is expected to be


  # an overlay for the specified base_container. podman-pilot


  # combines the 'container: name' with the base_container into


  # one overlay and starts the result as a container instance


  #


  # Default: not_specified


  base_container: name


  # Optional additional container layers on top of the


  # specified base container


  layers:


    - name_A


    - name_B


  # Optional registration setup


  # Container runtime parameters


  runtime:


    # Run the container engine as a user other than the


    # default target user root. The user may be either


    # a user name or a numeric user-ID (UID) prefixed


    # with the ‘#’ character (e.g. #0 for UID 0). The call


    # of the container engine is performed by sudo.


    # The behavior of sudo can be controlled via the


    # file /etc/sudoers


    runas: root


    # Resume the container from previous execution.


    # If the container is still running, the app will be


    # executed inside of this container instance.


    #


    # Default: false


    resume: true|false


    # Attach to the container if still running, rather than


    # executing the app again. Only makes sense for interactive


    # sessions like a shell running as app in the container.


    #


    # Default: false


    attach: true|false


    # Caller arguments for the podman engine in the format:


    # - PODMAN_OPTION_NAME_AND_OPTIONAL_VALUE


    # For details on podman options please consult the


    # podman documentation.


    # Example:


    podman:


      - --storage-opt size=10G


      - --rm


      - -ti

After reading of the app configuration information the application will be called using the configured engine. If no runtime arguments exists, the following defaults will apply:

All caller arguments will be passed to the program call inside of the instance except for arguments that starts with the '@' or '%' sign. Caller arguments of this type are only used for the podman-pilot startup itself. See the OPTIONS section for the available runtime options.

OPTIONS¶

@NAME

%silent

DEBUGGING¶

podman-pilot provides more inner works details if the following environment variable is set:

export PILOT_DEBUG=1

FILES¶

AUTHOR¶

Marcus Schäfer

COPYRIGHT¶

(c) 2022, Elektrobit Automotive GmbH (c) 2023, Marcus Schäfer