#752 Remove 'driver' from JDBC options, and try current thread context class loader for dynamically loaded JDBC drivers.

[yruslan]

Summary by CodeRabbit

• Refactor
  • Improved JDBC connection initialization with deferred driver loading. The system now loads the database driver at connection time rather than during initialization, with an intelligent fallback mechanism to handle different class loader contexts. This change enhances compatibility and flexibility across various deployment scenarios.

[coderabbitai]

Warning

Rate limit exceeded

@yruslan has exceeded the limit for the number of commits that can be reviewed per hour. Please wait 52 minutes and 59 seconds before requesting another review.

You’ve run out of usage credits. Purchase more in the billing tab.

⌛ How to resolve this issue?

After the wait time has elapsed, a review can be triggered using the @coderabbitai review command as a PR comment. Alternatively, push new commits to this PR.

We recommend that you space out your commits to avoid hitting the rate limit.

🚦 How do rate limits work?

CodeRabbit enforces hourly rate limits for each developer per organization.

Our paid plans have higher rate limits than the trial, open-source and free plans. In all cases, we re-allow further reviews after a brief timeout.

Please see our FAQ for further information.

ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: cc21eb1f-b595-44fa-9ea5-07a524960cef

📥 Commits

Reviewing files that changed from the base of the PR and between b220f08 and e1b8ae2.

📒 Files selected for processing (1)

• pramen/core/src/main/scala/za/co/absa/pramen/core/utils/JdbcNativeUtils.scala

Walkthrough

This pull request defers JDBC driver loading from initialization to connection time and adds fallback logic. The driver property is removed from connection properties, and driver loading is wrapped in a try/catch that retries using the thread context class loader if the default loader fails.

Changes

JDBC Driver Loading Deferral

Layer / File(s)	Summary
Remove driver from connection properties pramen/core/src/main/scala/za/co/absa/pramen/core/reader/JdbcUrlSelectorImpl.scala	Driver property is no longer added to the Properties object; user, password, database, and extraOptions remain unchanged.
Deferred driver loading with context class loader fallback pramen/core/src/main/scala/za/co/absa/pramen/core/utils/JdbcNativeUtils.scala	JDBC driver loading is deferred from initialization to connection time. The default class loader attempt is wrapped in try/catch; on ClassNotFoundException, the thread context class loader loads, instantiates, and registers the driver before opening the connection.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Poem

🐰 A driver hops along the path,
No longer loaded in a flash—
When connection time draws near,
Thread context loaders appear!
Fallback magic, smooth and swift,
ClassLoaders raise the JDBC gift. ✨

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately describes both main changes: removing the 'driver' property from JDBC options and implementing fallback to current thread context class loader for driver loading.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch bugfix/752-remove-driver-property

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[github-actions]

Unit Test Coverage

Overall Project	76.94% -0.06%	🍏
Files changed	12.33%	❌

Module	Coverage
pramen:core Jacoco Report	77.94% -0.07%	❌

Files

Module	File	Coverage
pramen:core Jacoco Report	JdbcUrlSelectorImpl.scala	76.1%	🍏
	JdbcNativeUtils.scala	62.29% -13.33%	❌

[yruslan]

@coderabbitai review

[coderabbitai]

✅ Actions performed

Review triggered.

Note: CodeRabbit is an incremental review system and does not re-review already reviewed commits. This command is applicable only when automatic reviews are paused.

[coderabbitai]

Actionable comments posted: 1

🧹 Nitpick comments (1)

pramen/core/src/main/scala/za/co/absa/pramen/core/utils/JdbcNativeUtils.scala (1)

213-214: ⚡ Quick win

Redundant class loading.

Class.forName(jdbcConfig.driver, true, loader) already loads and initializes the class, but its return value is discarded. The subsequent loader.loadClass(jdbcConfig.driver) call loads the same class again.

♻️ Proposed fix to use the return value directly

-        Class.forName(jdbcConfig.driver, true, loader)
-        val driverClass = loader.loadClass(jdbcConfig.driver)
+        val driverClass = Class.forName(jdbcConfig.driver, true, loader)

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In
`@pramen/core/src/main/scala/za/co/absa/pramen/core/utils/JdbcNativeUtils.scala`
around lines 213 - 214, The code redundantly loads the JDBC driver twice; remove
the extra loader.loadClass call and use the Class.forName return instead:
replace the two lines so that Class.forName(jdbcConfig.driver, true, loader) is
assigned to driverClass (or otherwise use its returned Class object) and then
proceed with existing logic that uses driverClass; update references to
driverClass accordingly and keep jdbcConfig.driver and loader as the identifying
symbols.

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In
`@pramen/core/src/main/scala/za/co/absa/pramen/core/utils/JdbcNativeUtils.scala`:
- Line 217: In JdbcNativeUtils (look for the driver.connect(url, properties)
call), add a null-check after Driver.connect to handle the case where the driver
declines the URL: if the returned connection is null, throw a clear
IllegalStateException (or SQLException) with a message mentioning the URL and
driver class instead of proceeding to use the null `connection` (which leads to
an NPE at connection.setAutoCommit); this ensures code paths in methods that use
the `connection` variable (e.g., wherever `autoCommit` is set) either get a
valid Connection or a descriptive error.

---

Nitpick comments:
In
`@pramen/core/src/main/scala/za/co/absa/pramen/core/utils/JdbcNativeUtils.scala`:
- Around line 213-214: The code redundantly loads the JDBC driver twice; remove
the extra loader.loadClass call and use the Class.forName return instead:
replace the two lines so that Class.forName(jdbcConfig.driver, true, loader) is
assigned to driverClass (or otherwise use its returned Class object) and then
proceed with existing logic that uses driverClass; update references to
driverClass accordingly and keep jdbcConfig.driver and loader as the identifying
symbols.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: 338c801e-154a-48a9-b4ba-f42d02a7abdc

📥 Commits

Reviewing files that changed from the base of the PR and between 98c77eb and b220f08.

📒 Files selected for processing (2)

• pramen/core/src/main/scala/za/co/absa/pramen/core/reader/JdbcUrlSelectorImpl.scala
• pramen/core/src/main/scala/za/co/absa/pramen/core/utils/JdbcNativeUtils.scala

💤 Files with no reviewable changes (1)

• pramen/core/src/main/scala/za/co/absa/pramen/core/reader/JdbcUrlSelectorImpl.scala