Add description to pools view

[vchiapaikeo]

closes: 34751

Expose description column in the pools view

Before:

After:

Not sure if it's okay to put styles inline. If I can refactor to a css file, please let me know.

---

^ Add meaningful description above
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[uranusjr]

I feel we should trim the string a bit, the description can be extremely long.

[vchiapaikeo]

Good call. What about some additional styling?

[uranusjr]

Is it possible to also do truncation when the rows are selected? Loading a long value into memory can be slow itself and bring down the entire view. I know it can be done with substr but the FAB model adds a layer on it.

[eladkal]

I feel we should trim the string a bit, the description can be extremely long.

What do we do in the Variable page? We have description column there as well.
@vchiapaikeo maybe we already have it handled there and we can just copy it?

[vchiapaikeo]

Ah yes, VariableModelView uses a custom FAB Model list_template and injects additional styling there. We can do something similar to get column resizing in PoolModelView:

However, to @uranusjr's point, we are still loading a potentially long value into memory. @uranusjr , when you say do truncation when the rows are selected, what do you think about adding a custom formatter and doing the slicing there?

[uranusjr]

No, I’m thinking if it’d be posible to apply substr on the column when the rows are selected from the database. That’s where the long strings get loaded. When you reach the renderer, the strings are already in memory and would already cause load on the server; a custom renderer is still better than only CSS (some bytes saved transfering HTML) but not too much different at that point.

[vchiapaikeo]

Ah I see. Wasn't sure if you were referring to browser memory or server memory. I profiled the render template code, and I'm not seeing an obvious place to add this. Are you thinking of something more custom on the sqlalchemy model? column_property or @hybrid_property come to mind but may be a bit overkill.

[vchiapaikeo]

@uranusjr , what are your thoughts on the previous comment? Sorry - forgot to tag ya.

[uranusjr]

Yeah I was wondering if Flask Appbuilder has a solution to this without needing to add something to the model. In Django admin you can add a method on the view class and point a column to it, for example. But I wouldn’t be surprised if there’s nothing similar; F.A.B. is not particularly known for being flexible… If you don’t see anything straightforward I can live with just adding custom styling like Variable for now and wait for people to complain (if they ever do).

[vchiapaikeo]

Did a bit of research on FAB and am not seeing anything obvious that would allow us to modify the underlying query being executed against the model. Rebasing and I think this should be good to go provided tests continue to pass.