feat: Add config to allow surpressing notification on launch (flag cache load) #2534

8ma10s · 2024-10-17T08:41:57Z

Description

This pull request introduces a new feature to disable notifications on initialization and refactors the caching mechanism to support this feature. It also includes updates to the test suite to ensure the new functionality works as expected.

Problem

go-feature-flag always sent notification of diff to all Notifierson ffClient initialization because it detects the difference between the initial cache (= always empty) and the flags retrieved.

Resolution

introduce DisableNotificationOnInit configuration key. If set to true, avoid sending the notification on cache initialization (it will still send notification when the change is detected AFTER initialization)
- Since the behavior (should) stays the same if the new config is NOT set, it should not introduce any breaking change.

How to test

I've added some tests to make sure the behavior stays the same when the new config is not explicitly set. You can run go test ./...
Or, simply initialize ffClient should do the trick too.

Closes issue(s)

Resolve #2532

Checklist

I have tested this code
I have added unit test to cover this code
I have updated the documentation (README.md and /website/docs)
I have followed the contributing guide

…tification

…nOnInit is set to true

netlify · 2024-10-17T08:42:12Z

✅ Deploy Preview for go-feature-flag-doc-preview canceled.

Name	Link
🔨 Latest commit	`ce61272`
🔍 Latest deploy log	https://app.netlify.com/sites/go-feature-flag-doc-preview/deploys/671a3df485f8e30008413b7a

codecov · 2024-10-17T08:49:12Z

Codecov Report

Attention: Patch coverage is 94.73684% with 1 line in your changes missing coverage. Please review.

Project coverage is 85.48%. Comparing base (a1955f0) to head (ce61272).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
cmd/relayproxy/service/gofeatureflag.go	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2534      +/-   ##
==========================================
+ Coverage   85.39%   85.48%   +0.09%     
==========================================
  Files         100      100              
  Lines        4436     4444       +8     
==========================================
+ Hits         3788     3799      +11     
+ Misses        518      516       -2     
+ Partials      130      129       -1

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

This also aligns the interval with rest of the test code

8ma10s · 2024-10-22T00:00:01Z

Sorry about the repeated commits. I think I've fixed the issue, and hopefully it works now.

thomaspoignant

Thanks a lot for this PR @8ma10s this is really great.

I like your approach but I will tend to simplify it a bit by just adding some parameters rather than creating new functions that can be hard to understand what is happening.
Would it work for you too?

thomaspoignant · 2024-10-22T20:38:59Z

cmd/relayproxy/config/config.go

+	// DisableNotificationOnInit (optional) set to true if you do not want to
+	// send a notification when the flags are loaded.
+	// This is useful if you do not want a Slack/Webhook notification saying that
+	// the flags have been added every time you start the application.
+	// Default is set to false for backward compatibility.
+	// Default: false
+	DisableNotificationOnInit bool `mapstructure:"disableNotificationOnInit" koanf:"disablenotificationoninit"`


While I understand why you've put notification here, but I think it will be more explicit to use the name notifier which is what we are using everywhere.

Suggested change

// DisableNotificationOnInit (optional) set to true if you do not want to

// send a notification when the flags are loaded.

// This is useful if you do not want a Slack/Webhook notification saying that

// the flags have been added every time you start the application.

// Default is set to false for backward compatibility.

// Default: false

DisableNotificationOnInit bool `mapstructure:"disableNotificationOnInit" koanf:"disablenotificationoninit"`

// DisableNotifierOnInit (optional) set to true if you do not want to

// send a notification when the flags are loaded.

// This is useful if you do not want a Slack/Webhook notification saying that

// the flags have been added every time you start the application.

// Default is set to false for backward compatibility.

// Default: false

DisableNotifierOnInit bool `mapstructure:"disableNotificationOnInit" koanf:"disablenotificationoninit"`

I think it makes sense, thank you. Yes, "notification" does seem a bit vague (as there can be other kinds of notifications), but "notifier" in this repo's context is pretty clear. Let me change that 👍

thomaspoignant · 2024-10-22T20:39:31Z

config.go

+	// DisableNotificationOnInit (optional) set to true if you do not want to send
+	// a notification when the flags are loaded.
+	// This is useful if you do not want a Slack/Webhook notification saying that
+	// the flags have been added every time you start the application.
+	// Default is set to false for backward compatibility.
+	// Default: false
+	DisableNotificationOnInit bool


Same as before

Suggested change

// DisableNotificationOnInit (optional) set to true if you do not want to send

// a notification when the flags are loaded.

// This is useful if you do not want a Slack/Webhook notification saying that

// the flags have been added every time you start the application.

// Default is set to false for backward compatibility.

// Default: false

DisableNotificationOnInit bool

// DisableNotifierOnInit (optional) set to true if you do not want to send

// a notification when the flags are loaded.

// This is useful if you do not want a Slack/Webhook notification saying that

// the flags have been added every time you start the application.

// Default is set to false for backward compatibility.

// Default: false

DisableNotifierOnInit bool

feature_flag.go

thomaspoignant · 2024-10-22T20:44:10Z

feature_flag.go

+}
+
+// retrieveFlagsAndInitializeCache is called when the feature flag is initialized
+func retrieveFlagsAndInitializeCache(config Config, cache cache.Manager, retrieverManager *retriever.Manager) error {


Rather having almost the same function for retrieveFlagsAndInitializeCache and retrieveFlagsAndUpdateCache I would have prefer to add a parameter to the previous function retrieveFlagsAndUpdateCache and use the same code on both side.

Something like

func retrieveFlagsAndUpdateCache(config Config, cache cache.Manager, retrieverManager *retriever.Manager, isInitialization bool) error { // ... if isInitialization && config.DisableNotificationOnInit { err = cache.UpdateCache(newFlags, config.internalLogger) } else { err = cache.UpdateCacheAndNotify(newFlags, config.internalLogger) }

Same deal as here: #2534 (comment)

I think I just tend to prefer having explicit function/method names just to make it a bit more readable on the caller code and avoid introducing too many parameters in a single method, but I think either works. To make it consistent with the code on the above comment, let me change this one as well 👍

thomaspoignant · 2024-10-22T20:48:53Z

internal/cache/cache_manager.go

 func (c *cacheManagerImpl) UpdateCache(newFlags map[string]dto.DTO, log *fflog.FFLogger) error {
+	return c.updateCache(newFlags, log, false)
+}
+
+func (c *cacheManagerImpl) UpdateCacheAndNotify(newFlags map[string]dto.DTO, log *fflog.FFLogger) error {
+	return c.updateCache(newFlags, log, true)
+}


Do we need those functions or should we just keep UpdateCache with the new parameter?

Conclusion

Sure, I think I can change the code to do that. Let me change my code.
Given that it's an internal interface that's not meant to be used by anything outside of this repo's code, I think we don't need to care so much for readability (or method clarity) as much as I initially thought.

My initial thought

I just thought that, given that CacheManager is (technically) defined as an interface, it would be beneficial to have a separate method to clearly indicate what the method is doing on the inside, rather than having an argument that doesn't really convey anything to the reader of the code.

What I mean is, if I have a code that calls this method defined in the interface, it would be (slightly) easier for the readers to understand what's going on when written like

err = cache.UpdateCacheAndNotify(newFlags, config.internalLogger) // do other stuff...

rather than

err = cache.UpdateCache(newFlags, config.internalLogger, true) // do other stuff...

because the value of true doesn't really convey anything just by reading it, whereas the method name UpdateCacheAndNotify clearly tells that it's gonna "notify something".

… of `CacheManager`

… indicate initialization

8ma10s · 2024-10-23T00:05:05Z

feature_flag.go


-	err := cache.UpdateCache(newFlags, config.internalLogger)
+	err = cache.UpdateCache(newFlags, config.internalLogger, isInit && !config.DisableNotifierOnInit)


Since we don't want to introduce breaking changes, we have to make false to be the original behavior, so that the default behavior would be same as the behavior before this PR. This is why we're making the config value name to be disableNotiferOnInit, and it's making this boolean logic slightly more difficult to read by introducing double negation.

Hopefully at some point, this repo makes the decision to make disabling the notifier the default behavior.
At that point, we can make the config value name to be enableNotifierOnInit (without negation, and that should make this code much easier to read:

err = cache.UpdateCache(newFlags, config.internalLogger, isInit && config.EnableNotifierOnInit)

Inverting the logic is something I am open with but we will need to explicitly guide GOFF users about this change in the future.

I'll keep it in mind in the potential breaking changes for the future.

thomaspoignant

Thanks again, we are almost ready to go and to merge this PR.

I have just put some comments on the mocks because we can probably reuse the existing one instead of creating new ones.

thomaspoignant · 2024-10-23T19:40:03Z

feature_flag.go


-	err := cache.UpdateCache(newFlags, config.internalLogger)
+	err = cache.UpdateCache(newFlags, config.internalLogger, isInit && !config.DisableNotifierOnInit)


Inverting the logic is something I am open with but we will need to explicitly guide GOFF users about this change in the future.

I'll keep it in mind in the potential breaking changes for the future.

feature_flag_test.go

internal/cache/cache_manager_test.go

variation_test.go

website/docs/go_module/configuration.md

website/docs/relay_proxy/configure_relay_proxy.md

…st files

thomaspoignant · 2024-10-24T12:30:37Z

Thanks a lot for your contribution @8ma10s this is really great.

sonarcloud · 2024-10-24T12:31:18Z

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

8ma10s · 2024-10-24T22:59:12Z

@thomaspoignant Thank you for reviewing and giving me suggestions! 🚀

8ma10s added 6 commits October 17, 2024 10:19

Change the existing UpdateCache method to UpdateCacheAndNotify

44a87b2

Add config to control whether to notify on application init

35e4274

Add a method to the cacheManager interface to update cache without no…

60c158c

…tification

Don't send notification on cache initialization if DisableNotificatio…

ec669de

…nOnInit is set to true

Update docs to refer to the newly available configuration

f790787

Fix golangci-lint errors

ea65873

github-actions bot assigned thomaspoignant Oct 17, 2024

github-actions bot requested a review from thomaspoignant October 17, 2024 08:42

8ma10s changed the title ~~Skip notification on launch~~ feat: Add config to allow surpressing notification on launch (flag cache load) Oct 17, 2024

Make the wait longer to ensure that async call has completed

fa5dda7

This also aligns the interval with rest of the test code

8ma10s marked this pull request as ready for review October 17, 2024 09:09

8ma10s marked this pull request as draft October 17, 2024 22:36

Add mutext to prevent race condition

ad3bf62

8ma10s marked this pull request as ready for review October 18, 2024 08:51

thomaspoignant and others added 2 commits October 21, 2024 13:36

Merge branch 'main' into skip-notification-on-launch

9b46412

use wasNotifyCalled() instead of directly calling notifyCalled

f4f62dc

thomaspoignant reviewed Oct 22, 2024

View reviewed changes

8ma10s added 4 commits October 23, 2024 08:21

DisableNotificationOnInit -> DisableNotifierOnInit

09852d0

Reduce number of interface methods by exposing the internal parameter…

b282acc

… of `CacheManager`

Introduce an additional parameter to retrieveFlagsAndUpdateCache to…

eac35b7

… indicate initialization

Add comment to retrieveFlags to indicate its functionality

e39b7d1

8ma10s commented Oct 23, 2024

View reviewed changes

8ma10s requested a review from thomaspoignant October 23, 2024 00:23

thomaspoignant requested changes Oct 23, 2024

View reviewed changes

8ma10s added 3 commits October 24, 2024 09:29

Use mocks from testutils/mock instead of creating mocks within the te…

85d7cb4

…st files

Remove unnecessary references to / declarations of UpdateCacheAndNotify

86d93e3

Fix README description to be more accurate about DisableNotifierOnInit

b064acb

8ma10s requested a review from thomaspoignant October 24, 2024 00:46

Reduce length of the line to comply with linter

2783fa1

thomaspoignant approved these changes Oct 24, 2024

View reviewed changes

Merge branch 'main' into skip-notification-on-launch

d267719

Merge branch 'main' into skip-notification-on-launch

ce61272

thomaspoignant added the automerge label Oct 24, 2024

kodiakhq bot merged commit 1351a3f into thomaspoignant:main Oct 24, 2024
22 checks passed

BrewTestBot mentioned this pull request Oct 24, 2024

go-feature-flag-relay-proxy 1.37.0 Homebrew/homebrew-core#195443

Merged

8ma10s mentioned this pull request Oct 24, 2024

fix: Notifier should fire during runtime (if isInit is false) #2569

Merged

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

feat: Add config to allow surpressing notification on launch (flag cache load) #2534

feat: Add config to allow surpressing notification on launch (flag cache load) #2534

8ma10s commented Oct 17, 2024

netlify bot commented Oct 17, 2024 •

edited

Loading

codecov bot commented Oct 17, 2024 •

edited

Loading

8ma10s commented Oct 22, 2024

thomaspoignant left a comment

thomaspoignant Oct 22, 2024

8ma10s Oct 22, 2024

thomaspoignant Oct 22, 2024

thomaspoignant Oct 22, 2024

8ma10s Oct 22, 2024

thomaspoignant Oct 22, 2024

8ma10s Oct 22, 2024

8ma10s Oct 23, 2024

thomaspoignant Oct 23, 2024

thomaspoignant left a comment

thomaspoignant Oct 23, 2024

thomaspoignant commented Oct 24, 2024

sonarcloud bot commented Oct 24, 2024

8ma10s commented Oct 24, 2024


		err := cache.UpdateCache(newFlags, config.internalLogger)
		err = cache.UpdateCache(newFlags, config.internalLogger, isInit && !config.DisableNotifierOnInit)

feat: Add config to allow surpressing notification on launch (flag cache load) #2534

feat: Add config to allow surpressing notification on launch (flag cache load) #2534

Conversation

8ma10s commented Oct 17, 2024

Description

Closes issue(s)

Checklist

netlify bot commented Oct 17, 2024 • edited Loading

✅ Deploy Preview for go-feature-flag-doc-preview canceled.

codecov bot commented Oct 17, 2024 • edited Loading

Codecov Report

8ma10s commented Oct 22, 2024

thomaspoignant left a comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

Conclusion

My initial thought

Choose a reason for hiding this comment

Choose a reason for hiding this comment

thomaspoignant left a comment

Choose a reason for hiding this comment

Choose a reason for hiding this comment

thomaspoignant commented Oct 24, 2024

sonarcloud bot commented Oct 24, 2024

Quality Gate passed

8ma10s commented Oct 24, 2024

netlify bot commented Oct 17, 2024 •

edited

Loading

codecov bot commented Oct 17, 2024 •

edited

Loading