Introduction

ZOO Calrissian Runner provides a bridge between the ZOO Project and Calrissian using pycalrissian.

The goal is to ease the development of runners that implement a business logic for the EOEPCA ADES Zoo implementation.

A runner provides an execution engine for Zoo. This repository and documentation provides a runner for Kubernetes using Calrissian.

Below an overview of the building block

Service deployment

When a service is deployed, the ADES instantiates a cookiecutter processing service template.

The scaffolded service folder contains a service.py Python file that executes the Application Package.

The service.py must implement a function with the signature:

def {{cookiecutter.workflow_id | replace("-", "_")  }}(conf, inputs, outputs):

And return zoo.SERVICE_SUCCEEDED if the execution is a success or zoo.SERVICE_FAILED if failed.

It must also implement an ExecutionHandler.

The ExecutionHandler is a abstract class defined as follows:

from abc import ABC, abstractmethod


class ExecutionHandler(ABC):
    def __init__(self, **kwargs):
        self.__dict__.update(kwargs)
        self.job_id = None

    def set_job_id(self, job_id):
        self.job_id = job_id

    @abstractmethod
    def pre_execution_hook(self):
        pass

    @abstractmethod
    def post_execution_hook(self):
        pass

    @abstractmethod
    def get_secrets(self):
        pass

    @abstractmethod
    def get_pod_env_vars(self):
        pass

    @abstractmethod
    def get_pod_node_selector(self):
        pass

    @abstractmethod
    def handle_outputs(self, execution_log, output, usage_report, tool_logs=None):
        pass

    @abstractmethod
    def get_additional_parameters(self):
        pass

Service execution

The service execution follows the ZooCalrissianRunner execution defined in its execute method.

What EOEPCA provides

EOEPCA provides:

• a example of a Zoo service template in the https://github.com/EOEPCA/proc-service-template software repository
• an implementation including the interaction with the Workspace API and the Catalog in the https://github.com/EOEPCA/eoepca-proc-service-template software repository

Other service template can of course be implemented with different business logics and interfacing with other systems or APIs.