Adding PNG support and enabling experimental reader in kwargs

[ktsitsi]

This PR:

• Enables the experimental_reader in the Cloud-py ingestor which was introduced in tiledb-bioimg 0.3.0 and onwards
• Incorporates the new PNG converter for use in cloud ingestion

[sgillies]

@ktsitsi "experimental_reader" sounds like a feature that might go away in the future or become the new default, at which we'd want to remove the option.

Is there a way that we can support more than one reader without using a flag that will eventually become deprecated? What about reader=experimental and reader=production (the default)?

[ktsitsi]

@ktsitsi "experimental_reader" sounds like a feature that might go away in the future or become the new default, at which we'd want to remove the option.

Is there a way that we can support more than one reader without using a flag that will eventually become deprecated? What about reader=experimental and reader=production (the default)?

Indeed it is the latter the experimental reader will be the new default. I will change it as you recommend and I will assign the selection inside the function so we avoid the depreciation.

[sgillies]

Sounds good @ktsitsi !

[ihnorton]

Should this be an enum?

[ktsitsi]

You are right @ihnorton I changed it in my last commit. I just thought that since the old reader is about to be deprecated once the experimental becomes the default one, that I did not want to over-engineer it. But it is cleaner this way thanks!

[sgillies]

@ktsitsi I made a suggestion/question inline.

[sgillies]

@ktsitsi how about making reader a named keyword argument of ingest() instead?

I'm doing a deep dive into our ingestion code right now and the way we have been moving things in and out of kwargs obfuscates the code.

[ktsitsi]

It indeed does however, the reason I did not do it in the first place is to avoid deprecating it later and breaking the API in the next releases.