feat: add support for Parquet options

[plamut]

Closes #661.

For load jobs and external tables config.

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• Ensure the tests and linter pass
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• Appropriate docs were updated (if necessary)

[google-cla]

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[plamut]

We still need to expose ParquetOptions in the google.cloud.bigquery namespace to be consistent with enums, etc.

[tseaver]

@googlebot I fixed it.

[google-cla]

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[google-cla]

We found a Contributor License Agreement for you (the sender of this pull request), but were unable to find agreements for all the commit author(s) or Co-authors. If you authored these, maybe you used a different email address in the git commits than was used to sign the CLA (login here to double check)? If these were authored by someone else, then they will need to sign a CLA as well, and confirm that they're okay with these being contributed to Google.
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[plamut]

Exposed the config object in google.cloud.bigquery namespace and also made sure that parquet_options works well with the options attribute.

[simonvanderveldt]

@plamut My team is currently a bit blocked because this functionality is missing from the BigQuery Python library. Is there anything we can do to help this get merged and released? Maybe some testing?

[plamut]

@simonvanderveldt Thanks for bumping this, it appears that it's incorrectly blocked by the CLA bot (and still needs one approval).

@shollyman Can you please convince the bot to change its mind? :) And add a review, if possible?

Is there anything we can do to help this get merged and released? Maybe some testing?

If you want, you can test the BigQuery client with this PR branch, but primarily someone from Google with sufficient permissions needs to unblock the PR first.

[simonvanderveldt]

If you want, you can test the BigQuery client with this PR branch, but primarily someone from Google with sufficient permissions needs to unblock the PR first.

Just tested it, working as expected :) We only need the list inference and using the library from this PR gives the same results as when using bq load --parquet_enable_list_inference.

[googlebot]

We found a Contributor License Agreement for you (the sender of this pull request), but were unable to find agreements for all the commit author(s) or Co-authors. If you authored these, maybe you used a different email address in the git commits than was used to sign the CLA (login here to double check)? If these were authored by someone else, then they will need to sign a CLA as well, and confirm that they're okay with these being contributed to Google.
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[stephaniewang526]

Looks like we're missing CLA signing from tseaver@palladion.com

[plamut]

But Tres is a well-known contributor? Or is it because a different email address was used?

[busunkim96]

@plamut I looks like there is no CLA for tseaver@palladion.com. @tseaver's CLA lists tres.seaver@gmail.com.

I think if you edit the Co-authored-by: Tres Seaver <tseaver@palladion.com> in the commit body the CLA bot will be appeased. Please holler if that doesn't work.

[google-cla]

CLAs look good, thanks!

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[plamut]

That trick with editing the commit message worked, great! Since we also have an approval now, I'll merge and release this today.

[plamut]

@busunkim96 As for the CLA bot, isn't this a bit fragile? Theoretically one could take another person's work posted as a suggestion, edit out the line in the commit message linking to that person, and then merge a non-CLA code into the project?

We can discuss this offline.

[plamut]

@simonvanderveldt The changes have just been released, happy coding!

[simonvanderveldt]

@plamut Awesome! Thanks a lot for the quick merge and release!

[tseaver]

@busunkim96 literally all of my commits to Google's repositories over the last seven years have been signed with the tseaver@palladion.com email address. The CLAbot seems flaky / fragile for commits which are merges of through-the-web suggestions.