Uprade gobreaker version to 0.5.0

[sagynbek]

💸 TL;DR

Update gobreaker version from 0.4.1 to 0.5.0, which adds IsSuccess to Config

📜 Details

We want to be able to customize the default behavior of IsSuccess, which defaults to check: if err is nil then it's successful, if err is non-nill then it's error
Outcome: By exposing IsSuccess to user, user will be able to make more thorough check

🧪 Testing Steps / Validation

✅ Checks

• CI tests (if present) are passing
• Adheres to code style for repo
• Contributor License Agreement (CLA) completed if not a Reddit employee

[fishy]

The majority of our code using breaker is like this:

resp, err := breaker.Execut(func() (any, error) {
  resp, err := actualCall(...)
  return resp, err
})

which means the feature IsSuccessful provided can easily be achieved via:

var resp respType
var err error
breaker.Execut(func() (any, error) {
  resp, err = actualCall(...)
  if myIsSuccessful(err) {
    return resp, nil
  }
  return resp, err
})

so I don't think there's any urgency to merge this (as none of the use cases are actually blocked by this), I'd prefer to wait for some services actually try this to see how useful it is before proceeding.

[sagynbek]

That's good workaround, it could be useful for this case:

We get validation error, we don't want it to increase error count of Circuit breaker, but still want original err to exit function.

Counter argument might be, if it's validation error then probably resp is nil and we could use that to check? That would be right, but in general IsSuccess looks useful overall )) It's not urgent to merge, but might be included in next release?
cc: @fishy

[kylelemons]

Have you tested this version in production yet?

[sagynbek]

Have you tested this version in production yet?

Hey @kylelemons , how can I test in production? Just bump version, and test it on staging?

[kylelemons]

You can use go get to update the dependency in your own application, you do not need to update it in baseplate in order for you to update.

As was mentioned above, it also doesn't seem like IsSuccessful is needed given the usual patterns of gobreaker, in which case you wouldn't even need to make your own copy of NewFailureRatioBreaker to test out the ability, but you could copy that function into your own repo it looks like to validate IsSuccessful is working as you expect.

And by production, I do mean production, not staging :D.