Support multi update's argument

[fcoury]

Closes #486

This PR accepts the additional optional flag for multiple updates straight on the update command:

https://www.mongodb.com/docs/manual/reference/method/db.collection.update/#std-label-update-multi

Since there is no high level API to call update (only UpdateOne or UpdateMany), I added a test that uses the lower level RunCommand API, providing the expected update command payload document.

My strategy on this particular test was to add two documents with a same field (x: 1) and then update using multi: false UpdateOne first, and checking that only the first document was updated; and then update using multi: true UpdateMany making sure both documents were modified.

Checklist

• Tests are added for new functionality or fixed bugs.
• task all passes.

See CONTRIBUTING.md for more details.

[ferretdb-bot]

All committers have signed the CLA.

[codecov]

Codecov Report

Merging #790 (6c51fe8) into main (3eec3c2) will decrease coverage by 0.06%.
The diff coverage is 50.00%.

@@            Coverage Diff             @@
##             main     #790      +/-   ##
==========================================
- Coverage   62.51%   62.45%   -0.07%     
==========================================
  Files         231      231              
  Lines       10798    10810      +12     
==========================================
+ Hits         6750     6751       +1     
- Misses       3273     3284      +11     
  Partials      775      775              

Impacted Files	Coverage Δ
internal/handlers/tigris/msg_update.go	0.00% <0.00%> (ø)
internal/handlers/pg/msg_update.go	50.87% <100.00%> (+1.78%)	⬆️
internal/handlers/pg/pgdb/collections.go	54.86% <0.00%> (-5.31%)	⬇️
internal/util/version/version.go	55.00% <0.00%> (-5.00%)	⬇️
internal/handlers/pg/pgdb/databases.go	60.00% <0.00%> (+5.33%)	⬆️

Flag	Coverage Δ
integration	57.25% <50.00%> (-0.04%)	⬇️
mongodb	18.56% <0.00%> (-0.07%)	⬇️
pg	61.87% <100.00%> (-0.01%)	⬇️
tigris	22.61% <0.00%> (-0.06%)	⬇️
unit	24.99% <0.00%> (+0.16%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

[AlekSi]

Since there is no high level API to call update (only UpdateOne or UpdateMany)

I think they use update command under the hood, setting multi flag to false (or omitting it) and true

[fcoury]

Since there is no high level API to call update (only UpdateOne or UpdateMany)

I think they use update command under the hood, setting multi flag to false (or omitting it) and true

Updated the test case to use UpdateOne and UpdateMany. Also added an additional test case to make sure multi falls back to false when absent.

Now the behavior is the same when testing from the go driver and mongosh:

FerretDB

MongoDB

[fcoury]

Rebased from new main branch.

[fcoury]

Ready for review.

[AlekSi]

May you also port those changes to tigris/msg_update.go. No tests are necessary for that handler yet

[AlekSi]

@GinGin3203 PTAL if you have a moment :)

[rumyantseva]

It doesn't look correct to me, but maybe I just don't understand something.

[rumyantseva]

LGTM