DEBUG-3182 Rework DI loading #4239
Open
+202
−115
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
![datadog-datadog-prod-us1[bot]](https://avatars.githubusercontent.com/u/365230?s=60&v=4){kind=small}
Datadog ReportBranch report: ✅ 0 Failed, 22130 Passed, 1475 Skipped, 5m 19.32s Total Time |
ivoanjo
reviewed
Dec 19, 2024
Comment on lines
+80
to
+113
| # DI code tracker is instantiated globally before the regular set of | ||
| # components is created, but the code tracker needs to call out to the | ||
| # "current" DI component to perform instrumentation when application | ||
| # code is loaded. Because this call may happen prior to Datadog | ||
| # components having been initialized, we maintain the "current component" | ||
| # which contains a reference to the most recently instantiated | ||
| # DI::Component. This way, if a DI component hasn't been instantiated, | ||
| # we do not try to reference Datadog.components. | ||
| # In other words, this method exists so that we never attempt to call | ||
| # Datadog.components from the code tracker. | ||
| def current_component | ||
| LOCK.synchronize do | ||
| @current_components&.last | ||
| end | ||
| end | ||
|
|
||
| # To avoid potential races with DI::Component being added and removed, | ||
| # we maintain a list of the components. Normally the list should contain | ||
| # either zero or one component depending on whether DI is enabled in | ||
| # Datadog configuration. However, if a new instance of DI::Component | ||
| # is created while the previous instance is still running, we are | ||
| # guaranteed to not end up with no component when one is running. | ||
| def add_current_component(component) | ||
| LOCK.synchronize do | ||
| @current_components ||= [] | ||
| @current_components << component | ||
| end | ||
| end | ||
|
|
||
| def remove_current_component(component) | ||
| LOCK.synchronize do | ||
| @current_components&.delete(component) | ||
| end | ||
| end |
There was a problem hiding this comment.
If I understand your use-case well, you can maybe replace this with something along the lines of
components = Datadog.send(:components, allow_initialization: false)
di = components.di if componentsThis allows you to access the components without triggering initialization. This is something we use in for instance Datadog::Tracing.correlation to allow the API to be used, but not cause initialization as a side-effect.
Codecov ReportAttention: Patch coverage is
Additional details and impacted files@@ Coverage Diff @@
## master #4239 +/- ##
==========================================
- Coverage 97.74% 97.74% -0.01%
==========================================
Files 1355 1357 +2
Lines 82365 82384 +19
Branches 4230 4232 +2
==========================================
+ Hits 80510 80527 +17
- Misses 1855 1857 +2 ☔ View full report in Codecov by Sentry. |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
What does this PR do?
This PR separates the part of DI that is required for code tracker (which is the code tracker itself and the DI.current_component group of methods, plus exception classes) to be self-contained. Currently in master loading
datadog/di/initwould bring indatadog/dias well which is too much (for example, that would cause DI to attempt to load ActiveRecord contrib, which is definitely not the right time for it).Motivation:
Ensuring DI code tracker is loaded early without causing the rest of dd-trace-rb to be loaded early.
Change log entry
Yes: Improved early loading mechanism of dynamic instrumentation (
datadog/di/init).Additional Notes:
While this PR changes the behavior of
datadog/di/init, this behavior has not yet been documented anywhere and should not be used by customers.How to test the change?
Integration tests specifically for
datadog/di/initwill be added in a follow-up PR. The existing unit tests verify that basic DI functionality continues to operate correctly.