feat: add X-LaunchDarkly-Instance-Id header (SDK-2356)#162
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Generate a v4 UUID once per SDK instance in HttpConfigurationBuilderImpl.build and stamp it on the default headers map. Because the default headers are shared by the stream, poll, and event paths, every outbound request carries the same stable per-instance identifier without per-channel plumbing. Registers the "instance-id" capability with the contract test service so the cross-SDK harness can verify the header on stream, poll, and event requests. Updates header-comparison tests that constructed a fresh HttpConfiguration side-by-side with the one under test; the instance ID is per-build so those tests now compare other headers exactly and only assert presence of the instance ID header.
tanderson-ld
approved these changes
May 15, 2026
Generating X-LaunchDarkly-Instance-Id inside HttpConfigurationBuilderImpl.build() tied the value to a specific subsystem builder. Any code path that goes through HttpConfiguration would see a value, but other subsystems built from ClientContext (which is the canonical per-LDClient state holder) had no way to read the same id. Add an instanceId field, getter, and a nine-argument constructor variant to ClientContext. The eight-argument constructor auto-generates a v4 UUID for any caller that does not need to pass an explicit value; the copy constructor propagates the existing value, so derived ClientContext instances stay in sync. ClientContextImpl.fromConfig now generates the UUID once and threads it through each of the three ClientContext variants it constructs during LDClient init. HttpConfigurationBuilderImpl reads from ClientContext.getInstanceId() instead of generating its own. Existing tests in DefaultFeatureRequestorTest / LDConfigTest / StreamProcessorTest that already accounted for per-build randomness continue to work because each `clientContext(...)` they construct gets its own auto-generated id. Update HttpConfigurationBuilderTest to assert the new contract: the builder mirrors whatever id the context provides; two distinct ClientContexts produce distinct ids; one context produces a stable id across multiple builds. Verified locally with `./gradlew test` against lib/sdk/server: all 17 of 17 test classes pass, including 15 of 15 HttpConfigurationBuilderTest cases.
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kinyoklion
approved these changes
May 26, 2026
…SDK-2356) Previously the public single-arg `ClientContext(String sdkKey)` test-convenience constructor produced an internally inconsistent state: `defaultHttp(sdkKey)` built an HttpConfiguration whose default headers embedded one auto-generated UUID (via the inner minimalContext), and the outer delegated 8-arg constructor auto-generated a separate UUID for `this.instanceId`. As a result, `context.getInstanceId()` and `context.getHttp().getDefaultHeaders()` returned different values for `X-LaunchDarkly-Instance-Id` -- so consumer code that read the instance id via the getter would see a different identifier than the SDK actually placed on outbound requests. Generate the UUID once in a new private delegating constructor and thread it both into `defaultHttp(sdkKey, instanceId)` (so the headers carry it) and into the explicit instanceId argument of the 9-arg constructor (so the accessor returns the same value). Added a regression test in ClientContextImplTest that asserts these two accessors agree.
tanderson-ld
approved these changes
May 27, 2026
tanderson-ld
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May 28, 2026
🤖 I have created a release *beep* *boop* --- ## [7.14.0](launchdarkly-java-server-sdk-7.13.4...launchdarkly-java-server-sdk-7.14.0) (2026-05-28) ### Features * add X-LaunchDarkly-Instance-Id header (SDK-2356) ([#162](#162)) ([a363777](a363777)) * Drop persistent-store cache after FDv2 in-memory store init ([#167](#167)) ([90f14f1](90f14f1)) ### Bug Fixes * honor FDv1 fallback directive during initializer phase ([#158](#158)) ([b0a3957](b0a3957)) --- This PR was generated with [Release Please](https://github.com/googleapis/release-please). See [documentation](https://github.com/googleapis/release-please#release-please). <!-- CURSOR_SUMMARY --> --- > [!NOTE] > **Low Risk** > No runtime code in the diff—only version strings and changelog—so review risk is limited to verifying the tagged commits match the release notes. > > **Overview** > **Release Please** bumps **launchdarkly-java-server-sdk** from **7.13.4** to **7.14.0** in `.release-please-manifest.json`, `lib/sdk/server/gradle.properties`, `Version.SDK_VERSION`, and adds the **7.14.0** section to `CHANGELOG.md`. > > The diff is **version and changelog metadata only**; the listed product changes ship in the already-merged commits this release tags: **`X-LaunchDarkly-Instance-Id`** on outbound HTTP, dropping the persistent-store cache after FDv2 in-memory init, and honoring **FDv1 fallback** during the initializer phase. > > <sup>Reviewed by [Cursor Bugbot](https://cursor.com/bugbot) for commit 594728e. Bugbot is set up for automated code reviews on this repo. Configure [here](https://www.cursor.com/dashboard/bugbot).</sup> <!-- /CURSOR_SUMMARY --> Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
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Summary
Adds the
X-LaunchDarkly-Instance-Idheader to every outbound polling, streaming, and event request. Value is a v4 UUID generated once inHttpConfigurationBuilderImpl.build()(viaUUID.randomUUID()) and applied before user-supplied custom headers, matching the User-Agent / Authorization override convention.Three pre-existing tests outside the http-config test class were rebuilding
HttpConfigurationto derive an "expected" header set for exact-equality comparisons against outbound requests; with per-build UUIDs those assertions were updated to check presence rather than exact equality.Test plan
Note
Low Risk
Outbound HTTP header and context API extension for server-connection-minutes; no auth or data-path changes, covered by unit and contract tests.
Overview
Adds a per-LDClient v4 UUID on
ClientContext(getInstanceId()), generated once inClientContextImpl.fromConfigand reused across logging/HTTP bootstrap contexts so polling, streaming, and events share one stable id.HttpConfigurationBuilderImplsets default headerX-LaunchDarkly-Instance-Idfrom that context value (before custom headers, which may override). Fixesnew ClientContext(String)so default HTTP headers andgetInstanceId()match. Contract harness registers capabilityinstance-id. Tests assert UUID presence/stability/uniqueness instead of exact header maps where values differ per build.Reviewed by Cursor Bugbot for commit 44af5fd. Bugbot is set up for automated code reviews on this repo. Configure here.