Change connection_config from a string:string map to a map from Parqu…

[sofia-tekdatum]

Change the connection config from a map to a map<ParquetCipher : map>

This will allow us the flexibility of specifying a connection config for more than one external encryptor at a time.

Also changed in Cython bindings.

[github-actions]

Thanks for opening a pull request!

If this is not a minor PR. Could you open an issue for this pull request on GitHub? https://github.com/apache/arrow/issues/new/choose

Opening GitHub issues ahead of time contributes to the Openness of the Apache Arrow project.

Then could you also rename the pull request title in the following format?

GH-${GITHUB_ISSUE_ID}: [${COMPONENT}] ${SUMMARY}

or

MINOR: [${COMPONENT}] ${SUMMARY}

See also:

• Other pull requests
• Contribution Guidelines - Contributing Overview

[avalerio-tkd]

@sofia-tekdatum I don't understand this PR. Let's chat offline quickly to get more context.

[avalerio-tkd]

This is just the change in the connection_config to add the algorithm_enum as key. Discussed offline. Thanks.

[sofia-tekdatum]

@avalerio-tkd After discussin with @cristekdatum this afternoon, I added the changes to the Python bindings as well. Can you PTAL?

[avalerio-tkd]

LGTM+. I had a couple of questions, but not blocking to merge. Thanks.

[avalerio-tkd]

Why is this clear() needed? Are we reusing an auxiliary data struct? Let's add a comment.

[sofia-tekdatum]

Yes, clearing from the values of the previous iteration. Comment added.

[avalerio-tkd]

Any chance of these look ups failing? Seems to follow the pattern of the previous version, but just checking.

[sofia-tekdatum]

In this specific line no lookup is happening, but in general, no. If there is an incorrect value sent in as ParquetCipher the cipher_to_name and cipher_from_name methods will catch this and raise ValueErrors accordingly.