fix: HTTP connection eviction and gRPC keepalive

[Avinash-Kamath]

Summary

• ScalekitAuthClient: Configured PoolingHttpClientConnectionManager with explicit pool sizing (20 total, 10 per route) and added evictExpiredConnections() + evictIdleConnections(30s) to prevent stale pooled connections from being reused after the server has closed them
• ScalekitClient: Added gRPC keepalive (keepAliveTime=60s, keepAliveTimeout=10s, keepAliveWithoutCalls=true) to proactively detect dead channels before RPCs hit them

Test plan

• Full integration test suite passes (mvn test)
• Manually verified HTTP connection eviction by observing pool cleanup after 30s idle
• Verified gRPC keepalive compiles and connects to live environment

🤖 Generated with Claude Code

Summary by CodeRabbit

• Chores
  • Improved gRPC connection reliability with enhanced keepalive behavior for more stable connections.
  • Upgraded HTTP client pooling and idle-connection eviction for steadier request handling.
  • Release version bumped to 2.1.2.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: 728cf5fb-0053-4a04-bdab-e12c10d3270b

📥 Commits

Reviewing files that changed from the base of the PR and between 4b4ec8d and 21a2868.

📒 Files selected for processing (1)

• src/main/java/com/scalekit/ScalekitClient.java

🚧 Files skipped from review as they are similar to previous changes (1)

• src/main/java/com/scalekit/ScalekitClient.java

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Walkthrough

gRPC channel keepalive enabled (60s/10s, pings without active calls); HTTP client uses a pooled connection manager with eviction of expired/idle connections; project version and Constants.version bumped to 2.1.2.

Changes

Connection Resilience

Layer / File(s)	Summary
gRPC client keepalive configuration src/main/java/com/scalekit/ScalekitClient.java	Imports TimeUnit; configures gRPC ManagedChannel with 60s keepalive time, 10s keepalive timeout, and keepalive pings enabled without active calls.
HTTP client connection pooling and eviction src/main/java/com/scalekit/api/impl/ScalekitAuthClient.java	Adds PoolingHttpClientConnectionManager and TimeUnit imports; initializes CloseableHttpClient with pooled manager (max total and per-route limits), applies request timeouts, and evicts expired/idle connections.
Project version bump pom.xml, src/main/java/com/scalekit/internal/Constants.java	Maven <version> and Constants.version updated from 2.1.1 to 2.1.2.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Possibly related issues

• chore: Implement AutoCloseable and close() lifecycle for ScalekitClient and ScalekitAuthClient #65: Touches gRPC keepalive and HTTP connection management; related to connection lifecycle/AutoCloseable work.

Possibly related PRs

• scalekit-inc/scalekit-sdk-java#58: Overlaps on project/version updates in pom.xml and Constants.java.

Suggested reviewers

• AkshayParihar33

Poem

"I’m a rabbit in the code, I hop and I keep,
Pings that whisper steady so channels don’t sleep,
I tidy the sockets, idle threads swept,
Versions bumped higher — the changelog is kept,
I nibble bytes and watch connections sleep."

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately describes the main changes: HTTP connection eviction configuration in ScalekitAuthClient and gRPC keepalive settings in ScalekitClient.
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.

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✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix/stale-connection-grpc-keepalive

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[coderabbitai]

Actionable comments posted: 1

🤖 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 `@src/main/java/com/scalekit/api/impl/ScalekitAuthClient.java`:
- Around line 57-62: ScalekitAuthClient and ScalekitClient must manage their
pooled resources: make both classes implement AutoCloseable and add a close()
method that explicitly releases their resources — in ScalekitAuthClient call
httpClient.close() and also shut down the underlying connection manager used to
build httpClient (the PoolingHttpClientConnectionManager instance), and in
ScalekitClient keep the created ManagedChannel in a private field (e.g.,
channel) instead of a local variable and in close() call channel.shutdown() (and
await termination or call shutdownNow() as appropriate) to ensure the gRPC
channel is cleaned up; update constructors/fields to store these resources so
close() can access them.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

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

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: e5e45df9-1e63-445b-860e-62c497f90cd7

📥 Commits

Reviewing files that changed from the base of the PR and between 9d24257 and 938a11e.

📒 Files selected for processing (2)

• src/main/java/com/scalekit/ScalekitClient.java
• src/main/java/com/scalekit/api/impl/ScalekitAuthClient.java