Perf: Fix N+1s on partners csv export

[coalest]

Description

We are getting some timeouts in production for partners exports from an org with lots of partners. This fixes the N+1 query issues for these requests.

Type of change

• Bug/performance

How Has This Been Tested?

Test suite and manually. Although the current partners request spec is only testing for a 2XX HTTP response, so some specs need to be added.

[cielf]

I'm afraid It's not noticeably faster on a simple manual check once on the production branch and once with this branch for the bank in question. FWIW, They are quite light on the county information, though, -- < 40 out of the 770. This took around 15 seconds both on the production branch and this one.

So I hope/suspect the culprit is the providing_diapers and providing_period_supplies. This particular partner doesn't provide diapers at all.

[cielf]

Hey @dorner -- I asked Cory to look into this because one of the banks at Wednesday's meeting is seeing timeouts whenever they try to do the partners export. It's taking about 15 seconds on my local fwiw.

[coalest]

Ok i will refactor the export into a service and fix the other N+1s. It should drastically improve the performance.

[coalest]

@cielf I just pushed a commit that should remove all the N+1's from the partners export.

I can't seem to find specs testing the generated data for this partners export (neither for the Partner#generate_csv method nor for the /partners.csv request), which means I will first have to add specs that pass with the current request and then make sure my refactoring hasn't changed any behavior.

With that said, would you mind testing this branch locally since you have a production-like database on your computer. I wouldn't test it for correctness yet (because I have yet to write tests), but I would be interested to know if it fixes the timeout issue, or if I need to dig deeper.

If it's still slow on this branch, could you share the output from Rack Mini Profiler? How to:

1. Click on the export partner agencies button.
2. Refresh the page. (for some reason the profiling result from this button doesn't automatically get added to the current badge)
3. Click on the performance badge.
4. Click on the /partners.csv request, and then click "share" to see an output that is shareable.

Screenshot for reference:

[cielf]

1/ Much faster. I'll want to check the results next to a version from the prod branch. @dorner can you do a tech pass?
2/ Lint is failing -- also some tests, but I haven't looked at if they are related.
3/ (Mostly an aside) Looking at the results from this period bank, I have my doubts about the accuracy of the "Providing Period Supplies", but I need to check it against the production version to see if it's a problem introduced here. (I don't think it is.)

[cielf]

@coalest Hrm. They are not producing identical results -- one of them has quoted strings for all the areas that are blank, and the other doesn't. That makes it harder to tell if there are any substantive differences.

[coalest]

Yea this is just a rough draft so far, wasn't expecting all the tests to pass because I moved some methods around but haven't fixed the tests yet. Mostly wanted to see if the issue was due to the N+1's or from somewhere else. I will try to polish this up soon.

[cielf]

Followup on me wondering if the "Providing Period Supplies" is right -- this bank actually has a lot of partners that they haven't distributed to in the last year. I checked 10 that showed "N", and they matched. So let's not worry about that.

[coalest]

Moved the previous model export specs to the new export service. So all tests are passing.

Still need to write request specs to have more confidence that the behavior before and after this refactor isn't changing.