Quick start guide
=================

Quick start guide describes the simplest example that allows you to create and run your own lambda local or in
kubernetes cluster.

.. note::

     Here and below will be presented the simplest useless example of lambda. For applicable in real life cases,
     detailed requirements, lifecycle and other description see `detailed lambdas description <lambdas.html>`_.

Local lambda execution
----------------------

#) Create virtual environment and install `luna-lambda-tools` package. (available at `VL pypi <http://pypi.visionlabs.ru/>`_)

    .. code-block:: bash

        pip install --trusted-host pypi.visionlabs.ru --extra-index-url http://pypi.visionlabs.ru/root/public/+simple luna-lambda-tools

#) Create the main file:

    .. code-block::
       :caption: lambda_main.py

          from luna_lambda_tools import StandaloneLambdaRequest

          async def main(request: StandaloneLambdaRequest) -> dict:
              return {"request_length_in_bytes": len(request.body)}

#) Create file for lambda local execution (it only needs to execute lambda local):

    .. code-block::
       :caption: run.py

        from luna_lambda_tools.public.run import run

        if __name__ == "__main__":
            run(lambdaType="standalone")

#) Execute lambda using configuration from running instance of configurator:

    .. code-block:: bash

        python run.py --luna-config http://127.0.0.1:5070/1

    All requests to lambda must use `/main` endpoint.
    If there no errors on previous steps, when sending the following request, the following response will be received:

    .. code-block:: bash

        curl -X POST "http://127.0.0.1:8000/main" --data-binary 123

        >>> {"request_length_in_bytes":3}


Deploy lambda using `Luna lambda` into kubernetes cluster
---------------------------------------------------------

.. note::
    `Luna-Api` provides necessary methods to create and use lambdas at `lambda` section of openapi documentation.


#) `Luna-Lambda` requires kubernetes cluster to work with. It is possible to use
   `minikube <https://minikube.sigs.k8s.io/docs/start/>`_ as temporary solution for lambda development.

   To use minikube it needs to properly specify *CLUSTER* location setting, more information about configuration
   and settings available `here <./config.html#configuration-requirements>`_.

   There are also some additional requirements
   `for lambda <./lambda_requirements.html#lambda-general-python-code-requirements>`_
   and `kubernetes cluster <./lambda_requirements.html#kubernetes-cluster-requirements>`_.

#) Install and execute `Luna-Lambda` (see `installation chapter <./install.html>`_ for details).

#) Create zip-archive with `lambda_main.py` file from previous step of quick start guide.

#) Create lambda using zip-archive by making `lambda creation request <./_static/api.html#operation/createLambda>`_.

#) Wait for lambda starts and check its availability, see `lambda usage chapter <./lambda_usage.html>`_ for details.