[feature] Allow users to select the base image

[jesuino]

Feature Area

What feature would you like to see?

We should allow users to select the base image to execute the pipeline either from a pre-filled list of runtime images or allow the user to enter the runtime image directly from the Kale Left Pane.

This RFE could be split on two separated issues:

• Backend: Allow users to compile the pipeline and set a base image. Currently it seems that the base image is hard coded in the template that generates the Python DSL;
• Frontend: A list of images could be used and a dropbox could allow the user to select the base image for a specifc pipeline step and the Left Pane should have a dropbox to allow the user to set a default image for all the steps. This could be done in two separated issues: First: notebook level base image and later we can add in context edit to select the base image per step.

What is the use case or pain point?

Currently users have to manually modify the generated DSL to include a base Image, which is tedious and error prone.

Is there a workaround currently?

Generate the Python KFP DSL and manually modify it:

@kfp_dsl.component(
    base_image='python:3.10',
    packages_to_install=['kfp>=2.0.0',
                         'kubeflow-kale==1.0.0.dev13', 'random2'],
    pip_index_urls=['https://test.pypi.org/simple', 'https://pypi.org/simple'],
)
---

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[StefanoFioravanzo]

@jesuino I agree this is needed!

An interesting option to explore is also the following: detecting at runtime the notebook's image being used to develop the notebook, and use that one as a base image. This can sometimes be beneficial because organizations already are producing customized notebook images for their data scientists, with a number of libraries preinstalled that they use for day-to-day work.

We could design a default configuration that detects whether Kale is being run inside a Pod, and in that case detect the base image used by the Pod. We could then provide the means to override the base image with a custom one

[jesuino]

Related issue: #401