feat(shipping): delay international shipments via shippingSlowdown feature flag by tlee768 · Pull Request #3354 · open-telemetry/opentelemetry-demo

tlee768 · 2026-05-07T16:21:02Z

Summary

Add shippingSlowdown feature flag (default off) that introduces a 10-second delay for non-US shipping requests when enabled
Integrate with flagd via OFREP protocol, with OpenTelemetry tracing on flag evaluations
Add FLAGD_HOST and FLAGD_OFREP_PORT env vars and flagd dependency to docker-compose
Add comprehensive tests with injectable flag checker and configurable slowdown duration

Closes #346

Test plan

cargo test passes in src/shipping
docker compose up starts shipping service with flagd dependency
Verify no delay for US addresses regardless of flag state
Verify 10s delay for non-US addresses when shippingSlowdown flag is enabled
Verify no delay for non-US addresses when flag is disabled

Assisted-by: This contribution was prepared with the assistance of an AI development tool.

…wn feature flag Closes open-telemetry#346 Assisted-by: This contribution was prepared with the assistance of an AI development tool.

Assisted-by: This contribution was prepared with the assistance of an AI development tool.

… slowdown duration Assisted-by: This contribution was prepared with the assistance of an AI development tool.

…ependency to compose Assisted-by: This contribution was prepared with the assistance of an AI development tool.

Assisted-by: This contribution was prepared with the assistance of an AI development tool.

…w OTel API Assisted-by: This contribution was prepared with the assistance of an AI development tool.

Assisted-by: This contribution was prepared with the assistance of an AI development tool.

linux-foundation-easycla · 2026-05-09T20:31:33Z

The committers listed above are authorized under a signed CLA.

✅ login: tlee768 / name: tlee439 (024b8a2, 28192f5, 2cab5e2, 2cad430, 2d5aad3, 2e3539d, 30aeeac, 3108414, 3501c1c, 361df7b, 3de2ef0, 5476d2a, 672c4d5, 6e3b78a, 76fa075, 7b6b22e, 82945d7, 9297a87, 9450555, 9afc649, ac5de46, b5ff292, cabb716, cae3f18, d666969, d93c9b2)
✅ login: tlee768 / name: tlee768 (9b9884d)

awc::Client is !Send + !Sync (uses Rc internally), so it cannot be stored in a struct captured by the Send + Sync FlagChecker closure. Instead, store one Client per actix worker thread using thread_local!, initialized lazily on first use. Cloning the Client is cheap (bumps an Rc, not the pool). Assisted-by: This contribution was prepared with the assistance of an AI development tool.

The #[instrument] span was never bridged to OTel since tracing-opentelemetry is not wired up, so the span and its fields were silently dropped. Assisted-by: This contribution was prepared with the assistance of an AI development tool.

Assisted-by: This contribution was prepared with the assistance of an AI development tool.

ps48 · 2026-05-12T05:03:06Z

@tlee768 thanks for the contribution, can you please fix the markdownlint errors:

Command to run

  # Markdown lint (requires npm install first)
  make markdownlint

  # Or directly:
  npm install
  npx --no -p markdownlint-cli markdownlint -c .markdownlint.yaml <file>

Errors from the CI

 ./src/shipping/README.md:35:16 error MD060/table-column-style Table column style [Table pipe does not align with header for style "aligned"]
./src/shipping/README.md:35:26 error MD060/table-column-style Table column style [Table pipe does not align with header for style "aligned"]
./src/shipping/README.md:35:58 error MD060/table-column-style Table column style [Table pipe does not align with header for style "aligned"]
./src/shipping/README.md:36:31 error MD060/table-column-style Table column style [Table pipe does not align with header for style "aligned"]
./src/shipping/README.md:36:62 error MD060/table-column-style Table column style [Table pipe does not align with header for style "aligned"]

Replace closure-based FlagChecker type alias with an enum that supports generic evaluate::<T>() calls, enabling non-bool flags in the future. Assisted-by: This contribution was prepared with the assistance of an AI development tool.

…r methods Assisted-by: This contribution was prepared with the assistance of an AI development tool.

Copilot

Pull request overview

Adds a new shippingSlowdown feature flag (default off) to the Rust Shipping service to introduce an artificial delay for international (non‑US) /ship-order requests when enabled, using flagd’s OFREP REST API and emitting tracing around evaluations.

Changes:

Introduce a flagd OFREP client and a FlagChecker abstraction to evaluate shippingSlowdown (with a test mock path).
Apply a configurable slowdown delay in ship_order for non‑US addresses when the flag is enabled, and add request-path tests.
Wire flagd dependency + env vars into docker compose files and add the flag definition to demo.flagd.json.

Reviewed changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/shipping/src/shipping_service/feature_flag.rs	Adds a flagd OFREP HTTP client with OTel-instrumented requests and safe fallbacks.
src/shipping/src/shipping_service.rs	Adds `FlagChecker`, injects it + a slowdown duration into `ship_order`, and adds tests for US/international behavior.
src/shipping/src/main.rs	Registers `FlagChecker` and default slowdown duration into Actix app state.
src/shipping/README.md	Documents the new feature flag and related environment variables.
src/flagd/demo.flagd.json	Adds the `shippingSlowdown` flag definition (default variant `off`).
docker-compose.yml	Passes flagd OFREP env vars to shipping and adds `flagd` to `depends_on`.
docker-compose.minimal.yml	Same as full compose: env var pass-through and `flagd` dependency for shipping.
CHANGELOG.md	Notes the new shipping feature flag integration.

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

tlee768 · 2026-05-14T12:37:04Z

+            name = "ShippingSlowdown",
+            message = "Delaying international shipment due to shippingSlowdown feature flag"
+        );
+        actix_web::rt::time::sleep(**slowdown).await;


web::Data<T> wraps an Arc<T>, so Deref for web::Data<Duration> yields Arc<Duration>, not Duration directly. The double deref is correct:

*slowdown → Arc<Duration> (via web::Data::deref)

**slowdown → Duration (via Arc::deref)

This compiles and works as intended.

tlee768 · 2026-05-14T12:44:48Z

+    #[actix_web::test]
+    async fn test_ship_order_us_flag_on() {
+        let slowdown = std::time::Duration::from_millis(50);
+        let checker = FlagChecker::mock().with("shippingSlowdown", true);
+        let start = std::time::Instant::now();
+        let order = call_ship_order(Some(make_address("US")), checker, slowdown).await;
+        assert!(start.elapsed() < slowdown);


The US path does no sleeping — it's just mock flag evaluation + tracking ID generation. 50ms is well above what actix's test harness takes to process a trivial request, so this shouldn't flake in practice. If it does, we can bump the slowdown duration, but I'd rather not add complexity (tokio time mocking, etc.) preemptively.

puckpuck

Hey @tlee768 thanks for this, and I really want this to happen as a feature flag for the demo. There is an official flagd provider for rust that we should use here instead of a custom client and enum to manage the feature flag evaluation.

puckpuck · 2026-05-14T15:20:13Z

Why are we not using the open_feature_flagd provider for Rust instead of creating our own client here? https://docs.rs/open-feature-flagd/latest/open_feature_flagd/

…gd crate Use FlagdProvider from open-feature-flagd instead of a hand-rolled HTTP client, removing the FlagdClient wrapper and FlagChecker enum. The ship_order handler now takes dyn FeatureProvider directly, and tests use MockFeatureProvider from the open-feature crate. Assisted-by: This contribution was prepared with the assistance of an AI development tool.

Use the crate's default gRPC resolver (port 8013) instead of REST/OFREP (port 8016). Update docker-compose files to pass FLAGD_PORT instead of FLAGD_OFREP_PORT to the shipping service. Assisted-by: This contribution was prepared with the assistance of an AI development tool.

… up immediately The default RPC resolver wraps evaluations in an LRU cache with a 60s TTL, causing demo.flagd.json edits to be invisible until the cache expires. Setting cache_settings: None bypasses the cache and makes every evaluation a fresh gRPC unary call, matching the behaviour of the old OFREP client. Assisted-by: This contribution was prepared with the assistance of an AI development tool.

Narrow open-feature-flagd to the rpc feature only (drops reqwest, datalogic-rs, notify, semver, etc.). Remove manual FLAGD_HOST/PORT reads since FlagdOptions::default() already reads them from env. Assisted-by: This contribution was prepared with the assistance of an AI development tool.

Short-circuit the && so the gRPC call to flagd only happens when the address is outside the US. Assisted-by: This contribution was prepared with the assistance of an AI development tool.

puckpuck · 2026-05-19T17:00:38Z

Instead of a shippingSlowdown boolean flag, I think a intlShippingSlowdown integer flag with a default value of 0 is a better idea, will keep the code cleaner, and allow for more flexibility with the flag.

Doing this allows us to remove all DEFAULT_SLOWDOWN and the slowdown function parameter, since this is pulled from the featureflag itself now. If the flag doesn't exists we default it to 0 (no sleep).

…lShippingSlowdown flag The flag value itself now carries the delay in seconds (default 0), removing the need for DEFAULT_SLOWDOWN and the injected duration parameter. Assisted-by: This contribution was prepared with the assistance of an AI development tool.

tlee768 · 2026-05-19T21:29:07Z

Instead of a shippingSlowdown boolean flag, I think a intlShippingSlowdown integer flag with a default value of 0 is a better idea, will keep the code cleaner, and allow for more flexibility with the flag.

Doing this allows us to remove all DEFAULT_SLOWDOWN and the slowdown function parameter, since this is pulled from the featureflag itself now. If the flag doesn't exists we default it to 0 (no sleep).

Done

tlee768 added 6 commits May 7, 2026 12:13

feat(shipping): delay international shipments based on shippingSlowdo…

9297a87

…wn feature flag Closes open-telemetry#346 Assisted-by: This contribution was prepared with the assistance of an AI development tool.

feat(shipping): add OTel tracing to feature flag evaluation

2cad430

Assisted-by: This contribution was prepared with the assistance of an AI development tool.

test(shipping): add ship_order tests with injectable flag checker and…

d666969

… slowdown duration Assisted-by: This contribution was prepared with the assistance of an AI development tool.

test(shipping): add ship_order tests with injectable flag checker and…

30aeeac

… slowdown duration Assisted-by: This contribution was prepared with the assistance of an AI development tool.

feat(shipping): add FLAGD_HOST, FLAGD_OFREP_PORT env vars and flagd d…

b5ff292

…ependency to compose Assisted-by: This contribution was prepared with the assistance of an AI development tool.

docs: add shippingSlowdown feature flag entry to CHANGELOG

6e3b78a

Assisted-by: This contribution was prepared with the assistance of an AI development tool.

tlee768 requested a review from a team as a code owner May 7, 2026 16:21

github-actions Bot added docs-update-required Requires documentation update helm-update-required Requires an update to the Helm chart when released labels May 7, 2026

tlee768 marked this pull request as draft May 7, 2026 16:23

tlee768 added 8 commits May 9, 2026 14:19

fix(shipping): check HTTP status before parsing feature flag response

cabb716

Assisted-by: This contribution was prepared with the assistance of an AI development tool.

docs(shipping): document shippingSlowdown feature flag and env vars

5476d2a

Assisted-by: This contribution was prepared with the assistance of an AI development tool.

fix(shipping): match all common US country name variants

2cab5e2

Assisted-by: This contribution was prepared with the assistance of an AI development tool.

test(shipping): remove redundant US country variant tests

cae3f18

Assisted-by: This contribution was prepared with the assistance of an AI development tool.

fix(shipping): use tracing crate for feature flag spans instead of ra…

3108414

…w OTel API Assisted-by: This contribution was prepared with the assistance of an AI development tool.

fix(shipping): reuse HTTP client for feature flag requests via LazyLock

28192f5

Assisted-by: This contribution was prepared with the assistance of an AI development tool.

refactor(shipping): restructure feature flag as FlagdClient struct

361df7b

Assisted-by: This contribution was prepared with the assistance of an AI development tool.

refactor(shipping): restructure feature flag as FlagdClient struct

9afc649

Assisted-by: This contribution was prepared with the assistance of an AI development tool.

tlee768 force-pushed the feat/shipping-slowdown-flag branch 2 times, most recently from 3e754f0 to 9afc649 Compare May 9, 2026 20:51

tlee768 added 3 commits May 9, 2026 20:05

feat(shipping): log feature flag evaluation result

82945d7

Assisted-by: This contribution was prepared with the assistance of an AI development tool.

tlee768 force-pushed the feat/shipping-slowdown-flag branch from 9feecdc to 82945d7 Compare May 12, 2026 03:19

tlee768 marked this pull request as ready for review May 12, 2026 03:22

tlee768 added 3 commits May 12, 2026 15:03

refactor(shipping): move mock constructors into FlagChecker as builde…

ac5de46

…r methods Assisted-by: This contribution was prepared with the assistance of an AI development tool.

fix linting

76fa075

osullivandonal requested a review from Copilot May 13, 2026 13:19

Copilot started reviewing on behalf of osullivandonal May 13, 2026 13:21 View session

Copilot AI reviewed May 13, 2026

View reviewed changes

puckpuck requested changes May 14, 2026

View reviewed changes

tlee768 added 5 commits May 14, 2026 21:52

perf(shipping): skip flag evaluation for US addresses

3501c1c

Short-circuit the && so the gRPC call to flagd only happens when the address is outside the US. Assisted-by: This contribution was prepared with the assistance of an AI development tool.

tlee768 force-pushed the feat/shipping-slowdown-flag branch from 44e8cde to 3501c1c Compare May 15, 2026 03:36

tlee768 requested a review from puckpuck May 15, 2026 15:13

tlee768 and others added 2 commits May 16, 2026 11:40

Merge branch 'main' into feat/shipping-slowdown-flag

9b9884d

chore: merge upstream/main to resolve conflicts

7b6b22e

tlee768 force-pushed the feat/shipping-slowdown-flag branch from fb321e7 to 7b6b22e Compare May 18, 2026 19:30

tlee768 mentioned this pull request May 18, 2026

ShippingService should check FeatureFlagService if shipping outside the US takes a while #346

Open

Merge branch 'main' into feat/shipping-slowdown-flag

f7f9ebb

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

feat(shipping): delay international shipments via shippingSlowdown feature flag#3354

feat(shipping): delay international shipments via shippingSlowdown feature flag#3354
tlee768 wants to merge 29 commits into
open-telemetry:mainfrom
tlee768:feat/shipping-slowdown-flag

tlee768 commented May 7, 2026 •

edited

Loading

Uh oh!

linux-foundation-easycla Bot commented May 9, 2026 •

edited

Loading

Uh oh!

ps48 commented May 12, 2026 •

edited

Loading

Uh oh!

Copilot AI left a comment

Uh oh!

tlee768 May 14, 2026

Uh oh!

tlee768 May 14, 2026

Uh oh!

puckpuck left a comment

Uh oh!

puckpuck May 14, 2026

Uh oh!

tlee768 May 15, 2026

Uh oh!

puckpuck commented May 19, 2026

Uh oh!

tlee768 commented May 19, 2026

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

4 participants

Conversation

tlee768 commented May 7, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Summary

Test plan

Uh oh!

linux-foundation-easycla Bot commented May 9, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

ps48 commented May 12, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

Copilot AI left a comment

Choose a reason for hiding this comment

Pull request overview

Reviewed changes

Uh oh!

tlee768 May 14, 2026

Choose a reason for hiding this comment

Uh oh!

tlee768 May 14, 2026

Choose a reason for hiding this comment

Uh oh!

puckpuck left a comment

Choose a reason for hiding this comment

Uh oh!

puckpuck May 14, 2026

Choose a reason for hiding this comment

Uh oh!

tlee768 May 15, 2026

Choose a reason for hiding this comment

Uh oh!

puckpuck commented May 19, 2026

Uh oh!

tlee768 commented May 19, 2026

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

4 participants

tlee768 commented May 7, 2026 •

edited

Loading

linux-foundation-easycla Bot commented May 9, 2026 •

edited

Loading

ps48 commented May 12, 2026 •

edited

Loading