[AIRFLOW-5803] Update S3Hook import paths [AIP-21]

[mingrammer]

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[mik-laj]

Why did you add the AWS prefix? This is not in line with GCP operator naming guidelines. We have no general rules, so we can use the GCP if they make sense.

Maybe you would like to help with creating a document describing the general principles of naming operators. I will gladly add my comments. A spreadsheet with planned changes would also be helpful. I have these for GCP changes.

CC: @BasPH@potiuk

https://docs.google.com/document/d/1_rTdJSLCt0eyrAylmmgYc3yZr-_h51fVlnvMmWqhCkY/edit?ts=5bb72dfd#

[mingrammer]

As I mentioned here #6455 (comment), I just followed the current class naming conventions for other AWS operators/hooks.

So I'm a bit confused about which conventions I should follow.

[mik-laj]

I am not sure of the correct solution. Can you write about this problem on mailing list? I don't think there has been an official discussion yet about ordering class names for AWS. The only document that describes it is AIP-21

Case #6 Other isolated cases
There are other random cases of inconsistencies in the naming of classes. It is necessary to review the list of all classes and prepare a plan of change. Support from major cloud service providers will be useful.

My team has support from Google, so we have a plan that was presented in the integration guide.

[mingrammer]

I sent a new thread on the mailing list about it!

https://lists.apache.org/thread.html/5ed0ce4dfd77640d7464dc57d4fafc75e8aac44e016f87ca1be3a4a3@%3Cdev.airflow.apache.org%3E

[mingrammer]

According to some threads on the above mail (all the conventions were proposed by @BasPH), I think we should keep the name S3Hook as is.

So I'll fix the AWSS3Hook back to S3Hook, and will update all its import paths.

[mingrammer]

Done.

[codecov-io]

Codecov Report

Merging #6465 into master will decrease coverage by 0.62%.
The diff coverage is 100%.

@@ Coverage Diff @@## master #6465 +/- ##
==========================================
- Coverage 84.02% 83.39% -0.63% 
==========================================
Files 632 635 +3 Lines 36640 36679 +39 ==========================================
- Hits 30787 30590 -197 - Misses 5853 6089 +236

Impacted Files	Coverage Δ
airflow/contrib/hooks/wasb_hook.py	100% <ø> (ø)	⬆️
airflow/sensors/s3_key_sensor.py	100% <100%> (ø)	⬆️
airflow/contrib/operators/s3_to_gcs_operator.py	86.44% <100%> (ø)	⬆️
airflow/sensors/s3_prefix_sensor.py	100% <100%> (ø)	⬆️
...rflow/contrib/operators/s3_copy_object_operator.py	100% <100%> (ø)	⬆️
airflow/operators/google_api_to_s3_transfer.py	100% <100%> (ø)	⬆️
airflow/operators/gcs_to_s3.py	94.73% <100%> (ø)	⬆️
airflow/operators/redshift_to_s3_operator.py	97.14% <100%> (ø)	⬆️
...ontrib/operators/imap_attachment_to_s3_operator.py	100% <100%> (ø)	⬆️
airflow/operators/s3_to_redshift_operator.py	100% <100%> (ø)	⬆️
... and 65 more

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[mingrammer]

By the final voting result, It seems to have to move S3Hook into /providers/amazon/aws.

Should I update it with an another PR?

https://cwiki.apache.org/confluence/display/AIRFLOW/AIP-21%3A+Changes+in+import+paths#AIP-21:Changesinimportpaths-Votingresults(seevotingbelow)

[potiuk]

Ah. My bad @mingrammer. I was too fast. Can you please make another one to move to amazon.aws ?

[potiuk]

I actually had to revert it as it was failing without rebase. Can you please rebase/reopen and add amazon package?

[mingrammer]

Sure, I'll do!

[dazza-codes]

Related PR in #6764 for batch operator, so I need to follow all this API-21 stuff in a few places (although I'd prefer to just merge it and have the subsequent API-21 stuff applied in one larger PR, but looks like it's already piecemeal).

[ashb]

Related PR in #6764 for batch operator, so I need to follow all this API-21 stuff in a few places (although I'd prefer to just merge it and have the subsequent API-21 stuff applied in one larger PR, but looks like it's already piecemeal).

If you want to do one large rename PR I'm all for it - ping me if you want a reviewer on it :)