fix: enable persist_docs for views

[roslovets]

Description

Since Athena view is just a Glue table it's an omission that persist_docs feature is disabled for views. It works exactly the same as with Athena tables.

Checklist

• You followed contributing section
• You kept your Pull Request small and focused on a single feature or bug fix.
• You added unit testing when necessary
• You added functional testing when necessary

[Jrmyy]

Last time I implemented the feature there was an error when trying to put the comments in the glue view, leading to the view being unusable.
Can you give us a model to reproduce, have you tried to persist the docs ? Run the queries on the view afterwards ?

[roslovets]

I'm sorry, you are right. I thought, I tested it enough, but views don't work after creating.
Fortunately the problem is not Athena related. It's a bug in the current Glue logic implementation.
I'm working on fix and will provide it with test results soon.

[roslovets]

Current verison of adapter (1.5.0) breaks views when executing persistent_docs because some important fields of Glue Table representing Athena views are missing in source code: https://github.com/dbt-athena/dbt-athena/blob/ff479c147eb922119b774acb42375f924bc968a1/dbt/adapters/athena/impl.py#L647
Like 'ViewOriginalText' - the whole SQL code of view is truncated from view with current implementation.

I fixed updating of Glue table Description taking code from awswrangler library as a reference:
https://github.com/roslovets/dbt-athena/blob/main/dbt/adapters/athena/impl.py#L859

Now it works like a charm for tables and views updating Glue Table Description (straightforward way) and custom Parameter called 'comment' (optional, but useful for compatibility with common approach in databases world).

Additionally I put some efforts trying optimize creation of new version of Glue Tables during deployment. I think that ideally:

• you should have 1 new version of Glue Table after dbt run (not 2-3)
• for incremental tables: new version should not be created if descriptions (table+columns) were not modified in dbt project

Manual testing

View

First run of view model:

Populated: Table Description, Table 'comment' Property, Column Comment.

Only one version of table exists after single dbt run.

Deployed view works and it is selectable.

Seconf run of view model:

One Table Version added.

Table

We have two versions from scratch (this is a flaw in table creation process).

Incremental table

Initial run:

We have two versions right after creation (similar to previous example).

Second run (with the same model description in schema.yml):

Table description was not updated because there is no need to do it. No new Table Version was produced.

Third run (with new model description):

We have new Table Version with updated description.

Conclusion

Suggested fix is simple and it allows to populate model/columns descriptions to Glue Table for Athena views.

Tested and verified in my AWS environment.

[roslovets]

Thank you for checking this fix. It will help me to simplify postprocessing of Glue Tables deployed with dbt by custom scheduled script.

[Jrmyy]

Overall looks good, a few comments 🔥 👍🏻

[roslovets]

@Jrmyy Thanks a lot for your time and comments. I thinks I fixed it all.

[svdimchenko]

@roslovets great job done with updating table metadata 👍 🌟 🚀 ! Some minor comments, mostly about typing which will make the code more easy to understand.

[roslovets]

Guys, thank you for smart suggestions. It looks beter now.