fix: Normalize uppercase trace ids to lowercase in URL by samar-703 · Pull Request #3485 · jaegertracing/jaeger-ui

samar-703 · 2026-01-31T11:45:51Z

Which problem is this PR solving?

Resolves [Bug]: Uppercase trace IDs not normalizing to lowercase #3477

Description of the changes

Replaced broken class component normalization with useEffect hook
Uses useNavigate with replace option for URL normalization
Preserves query parameters during normalization
Updated test to match new implementation

How was this change tested?

All existing unit tests pass (87/87 tests in TracePage suite)
Updated the "forces lowercase id" test to verify new implementation behavior
Manually tested with uppercase trace ID: http://localhost:5173/trace/B36DE06C5972AB071AC119C504CA07DC successfully auto-normalizes to lowercase
Verified already-lowercase URLs don't trigger unnecessary redirects
TypeScript compilation successful

Checklist

I have read https://github.com/jaegertracing/jaeger/blob/master/CONTRIBUTING_GUIDELINES.md
I have signed all commits
I have added unit tests for the new functionality
I have run lint and test steps successfully
- for jaeger: make lint test
- for jaeger-ui: npm run lint and npm run test

github-actions · 2026-01-31T11:46:30Z

Hi @samar-703, thanks for your contribution! To ensure quality reviews, we limit how many concurrent open PRs new contributors can open.

This PR is currently on hold (Status: 2/1 open). We will automatically move this into the review queue once your existing PRs are merged or closed.

Please see our Contributing Guidelines for details on our tiered quota policy.

Copilot

Pull request overview

This PR refactors how trace ID URL normalization is handled for the Trace page so that uppercase trace IDs are normalized to lowercase at the routing layer, aiming to fix #3477 and to preserve query parameters.

Changes:

Moves trace ID normalization out of TracePageImpl.ensureTraceFetched into a useEffect hook in the functional TracePage wrapper that uses useNavigate from react-router-dom-v5-compat.
Uses useLocation to preserve the existing query string (location.search) during normalization redirects.
Updates the "forces lowercase id" test in index.test.js to stop asserting on history.replace and instead perform a minimal render assertion with an uppercase ID.

Reviewed changes

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

File	Description
packages/jaeger-ui/src/components/TracePage/index.tsx	Adds a hook-based URL-normalization step in the functional `TracePage` wrapper and removes the old `history.replace(getLocation(...))` logic from `TracePageImpl.ensureTraceFetched`.
packages/jaeger-ui/src/components/TracePage/index.test.js	Adjusts the `"forces lowercase id"` test to no longer rely on `history.replace` and to render `TracePageImpl` with an uppercase ID, but without asserting on the new navigation behavior.

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packages/jaeger-ui/src/components/TracePage/index.tsx

packages/jaeger-ui/src/components/TracePage/index.test.js

Parship12

LGTM 👍

we could do this with a simpler fix (by reordering logic in ensureTraceFetched), but since we are planning to convert this component to functional component with hooks, this approach makes sense as it moves us in that direction. I think we may need to reorganize the logic, but we can handle that during the full migration.

Parship12 · 2026-01-31T14:50:46Z

Screen.Recording.2026-01-31.194943.mp4

packages/jaeger-ui/src/components/TracePage/index.tsx

Copilot

Pull request overview

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packages/jaeger-ui/src/components/TracePage/index.test.js

packages/jaeger-ui/src/components/TracePage/index.tsx

yurishkuro

Please respond to copilot comments

Copilot

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packages/jaeger-ui/src/components/TracePage/index.tsx

samar-703 · 2026-02-01T19:41:35Z

Please respond to copilot comments

I've made the required changes to address the Copilot feedback:

removed the ineffective mock in the test file as suggested
fixed the navigation approach. I initially tried adding location.state to dependencies (which caused loops) and then using relative path ../ as you suggested, however, in React Router v5, relative paths resolve from the route match rather than URL segments, causing ../ to navigate to root /, which redirects to /search.

The solution is using the existing getUrl() utility function, which properly handles deployment URL prefixes via prefixUrl().

tested locally - uppercase trace IDs now normalize to lowercase without redirecting.

Note: Copilot is now suggesting adding tests for the wrapper component's normalization behavior. I can add those if needed, though it would require setting up proper mocking for the default export with router context. Let me know if you'd like me to add wrapper tests or if the current test coverage is sufficient for this fix.

packages/jaeger-ui/src/components/TracePage/index.tsx

Copilot

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packages/jaeger-ui/src/components/TracePage/index.integration.test.js

…ce ID normalization Signed-off-by: Samar <hello.samar7@gmail.com>

- normalize trace ID to lowercase before passing to component - preserve query parameters and location state during redirect - added integration tests for normalization and query param preservation. Signed-off-by: Samar <hello.samar7@gmail.com>

Signed-off-by: Samar <hello.samar7@gmail.com>

- Extract uppercase-to-lowercase normalization into useNormalizeTraceId hook - Hook handles redirect and preserves query params and location state - Replace integration test with focused unit tests for the hook - Simplifies TracePage component by removing inline navigation logic Fixes double-fetch caused by uppercase trace IDs in Redux store. Signed-off-by: Samar <hello.samar7@gmail.com>

Signed-off-by: Samar <hello.samar7@gmail.com>

Copilot

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Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

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packages/jaeger-ui/src/components/TracePage/index.test.js

codecov · 2026-03-07T05:42:56Z

Codecov Report

❌ Patch coverage is 83.33333% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 89.15%. Comparing base (4713873) to head (bc356ee).
⚠️ Report is 9 commits behind head on main.

Files with missing lines	Patch %	Lines
...kages/jaeger-ui/src/components/TracePage/index.tsx	33.33%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3485      +/-   ##
==========================================
+ Coverage   89.04%   89.15%   +0.10%     
==========================================
  Files         302      304       +2     
  Lines        9613     9719     +106     
  Branches     2547     2587      +40     
==========================================
+ Hits         8560     8665     +105     
- Misses       1050     1051       +1     
  Partials        3        3

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Copilot · 2026-03-07T19:56:50Z

packages/jaeger-ui/src/components/TracePage/index.tsx

 const TracePage = (props: TracePageProps) => {
  const config = useConfig();
+  const traceID = props.params.id;
+  const normalizedTraceID = useNormalizeTraceId(traceID);
+
  return (
    <ConnectedTracePage
      {...props}
+      params={{ ...props.params, id: normalizedTraceID }}
      archiveEnabled={Boolean(config.archiveEnabled)}


The URL-normalization behavior is implemented in the functional TracePage wrapper (hook call + passing a normalized params.id), but the existing index.test.js suite only renders TracePageImpl directly. The new unit tests cover useNormalizeTraceId(), but they don’t verify that the real TracePage route actually invokes the hook and performs navigation when params.id is uppercase. Adding a small integration test that renders the default export (withRouteProps wrapper) under a router and asserts useNavigate(..., { replace: true }) is called would prevent regressions where the hook is accidentally removed or the normalized params.id is no longer passed down.

jkowall · 2026-03-07T20:01:16Z

@samar-703 Update the copyright year to 2026 in the files to fix the CI issue. Also, is there a way to fix the drop in code coverage?

jkowall

Review

Summary

This PR extracts trace ID case normalization from the TracePageImpl class component's ensureTraceFetched method into a new useNormalizeTraceId custom hook used by the functional TracePage wrapper. This fixes #3477 where uppercase trace IDs in URLs caused issues.

+98 / -17 across 4 files (2 new, 2 modified)

What's Good

Clean separation of concerns: Extracting normalization into a dedicated hook is the right pattern, especially since the project is migrating toward functional components.
Query params preserved: The hook correctly appends location.search to the redirect URL.
Replace navigation: Using { replace: true } avoids polluting browser history.
Tests are well-structured: The hook tests cover the three key scenarios (uppercase -> redirect, query param preservation, already-lowercase -> no-op).

Issues & Suggestions

1. Bug: `location` in useEffect dependency causes infinite loop risk

useNormalizeTraceId.ts:20 — location.state is in the dependency array but location is a new object on every render in React Router. While location.search is a primitive string (safe), location.state is an object reference that can change identity without changing value, potentially causing unnecessary re-runs.

Suggestion: Remove location.state from the dependency array, or capture it with a ref. The redirect only needs to fire when traceID changes.

React.useEffect(() => {
  if (traceID && traceID !== normalizedTraceID) {
    const url = getUrl(normalizedTraceID);
    navigate(`${url}${location.search}`, { replace: true, state: location.state });
  }
}, [traceID, normalizedTraceID]); // navigate and location accessed via closure

2. Bug: `getUrl` mock in tests doesn't match real signature

useNormalizeTraceId.test.ts:15-17 — The mock getUrl: (id: string) => /trace/${id} ignores the optional uiFind parameter and more importantly, doesn't use prefixUrl(). This means tests won't catch issues with URL prefix handling. Consider using the real getUrl or at least documenting why the simplification is intentional.

3. Potential double-fetch still exists

The PR description mentions fixing "double-fetch caused by uppercase trace IDs in Redux store," but look at the flow:

TracePage renders with uppercase traceID
useNormalizeTraceId returns the lowercase ID immediately (before the effect fires)
ConnectedTracePage receives the lowercase ID and passes it to TracePageImpl
ensureTraceFetched calls fetchTrace(id) with the lowercase ID
The useEffect fires and triggers a navigation, which re-renders

This means fetchTrace is called with the correct lowercase ID on first render, but the navigation in step 5 causes a second render cycle. If React Router re-mounts the component on navigation, fetchTrace could be called again. Worth verifying this doesn't cause a double fetch.

4. `ensureTraceFetched` lost the early return

index.tsx:292-296 — The original code had:

if (!trace) {
  fetchTrace(id);
  return;  // <-- this early return was removed
}

The return was there to skip the normalization check below it. Now that the normalization check is gone, removing return is fine functionally. But note that the location destructuring was also removed from ensureTraceFetched, while location is still in the props type — just confirming that's intentional and location isn't used elsewhere in this method.

5. Test weakened for `TracePageImpl`

index.test.js:348-361 — The old test verified that history.replace was called with the correct lowercase path. The new test only checks expect(() => render(...)).not.toThrow(), which doesn't actually verify any behavior. Since normalization now lives in the wrapper, this is somewhat acceptable, but the test name "forces lowercase id" is now misleading — it should be renamed to something like "renders without error when given uppercase id".

6. Minor: `getLocation` is now unused

The diff removes the import of getLocation from index.tsx, but getLocation is still exported from url/index.ts. Verify no other consumers use it; if not, it should be removed to avoid dead code.

7. Copyright year

Verdict

The overall approach is sound and aligns with the project's direction toward hooks. The main concern is the location.state in the useEffect dependency array which could cause re-render loops in certain scenarios. The test coverage for the hook is good but the existing TracePageImpl test was weakened without a meaningful replacement assertion.

I'd suggest addressing issues #1 and #5 before merging.

jkowall

Review

Summary

This PR extracts trace ID case normalization from the TracePageImpl class component's ensureTraceFetched method into a new useNormalizeTraceId custom hook used by the functional TracePage wrapper. This fixes #3477 where uppercase trace IDs in URLs caused issues.

+98 / -17 across 4 files (2 new, 2 modified)

What's Good

Clean separation of concerns: Extracting normalization into a dedicated hook is the right pattern, especially since the project is migrating toward functional components.
Query params preserved: The hook correctly appends location.search to the redirect URL.
Replace navigation: Using { replace: true } avoids polluting browser history.
Tests are well-structured: The hook tests cover the three key scenarios (uppercase -> redirect, query param preservation, already-lowercase -> no-op).

Issues & Suggestions

1. Bug: `location` in useEffect dependency causes infinite loop risk

useNormalizeTraceId.ts:20 — location.state is in the dependency array but location is a new object on every render in React Router. While location.search is a primitive string (safe), location.state is an object reference that can change identity without changing value, potentially causing unnecessary re-runs.

Suggestion: Remove location.state from the dependency array, or capture it with a ref. The redirect only needs to fire when traceID changes.

React.useEffect(() => {
  if (traceID && traceID !== normalizedTraceID) {
    const url = getUrl(normalizedTraceID);
    navigate(`${url}${location.search}`, { replace: true, state: location.state });
  }
}, [traceID, normalizedTraceID]); // navigate and location accessed via closure

2. Bug: `getUrl` mock in tests doesn't match real signature

useNormalizeTraceId.test.ts:15-17 — The mock getUrl: (id: string) => /trace/${id} ignores the optional uiFind parameter and more importantly, doesn't use prefixUrl(). This means tests won't catch issues with URL prefix handling. Consider using the real getUrl or at least documenting why the simplification is intentional.

3. Potential double-fetch still exists

The PR description mentions fixing "double-fetch caused by uppercase trace IDs in Redux store," but look at the flow:

TracePage renders with uppercase traceID
useNormalizeTraceId returns the lowercase ID immediately (before the effect fires)
ConnectedTracePage receives the lowercase ID and passes it to TracePageImpl
ensureTraceFetched calls fetchTrace(id) with the lowercase ID
The useEffect fires and triggers a navigation, which re-renders

This means fetchTrace is called with the correct lowercase ID on first render, but the navigation in step 5 causes a second render cycle. If React Router re-mounts the component on navigation, fetchTrace could be called again. Worth verifying this doesn't cause a double fetch.

4. `ensureTraceFetched` lost the early return

index.tsx:292-296 — The original code had:

if (!trace) {
  fetchTrace(id);
  return;  // <-- this early return was removed
}

The return was there to skip the normalization check below it. Now that the normalization check is gone, removing return is fine functionally. But note that the location destructuring was also removed from ensureTraceFetched, while location is still in the props type — just confirming that's intentional and location isn't used elsewhere in this method.

5. Test weakened for `TracePageImpl`

index.test.js:348-361 — The old test verified that history.replace was called with the correct lowercase path. The new test only checks expect(() => render(...)).not.toThrow(), which doesn't actually verify any behavior. Since normalization now lives in the wrapper, this is somewhat acceptable, but the test name "forces lowercase id" is now misleading — it should be renamed to something like "renders without error when given uppercase id".

6. Minor: `getLocation` is now unused

The diff removes the import of getLocation from index.tsx, but getLocation is still exported from url/index.ts. Verify no other consumers use it; if not, it should be removed to avoid dead code.

7. Copyright year

Verdict

The overall approach is sound and aligns with the project's direction toward hooks. The main concern is the location.state in the useEffect dependency array which could cause re-render loops in certain scenarios. The test coverage for the hook is good but the existing TracePageImpl test was weakened without a meaningful replacement assertion.

I'd suggest addressing issues #1 and #5 before merging.

github-actions · 2026-03-07T20:07:43Z

PR quota unlocked!

@samar-703, this PR has been moved out of the waiting room and into the active review queue:

Open: 1
Limit: 2

Thank you for your patience.

- Fix copyright year to 2026 in new files - Remove location.state from useEffect deps to prevent re-render loops; navigate and location accessed via closure instead - Rename misleading test 'forces lowercase id' to accurately reflect that normalization now lives in the wrapper hook - Document simplified getUrl mock intent in hook unit tests Signed-off-by: Samar <hello.samar7@gmail.com>

samar-703 · 2026-03-08T12:48:38Z

@samar-703 Update the copyright year to 2026 in the files to fix the CI issue. Also, is there a way to fix the drop in code coverage?

done! updated copyright year to 2026 in both new files and added a DOM
assertion in index.test.js to recover the coverage drop on index.tsx.
Just pushed the fixes, CI should be passing shortly

jkowall

Looks good thanks for the contribution

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ui: normalize trace IDs to lowercase before fetch #3486

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Fix: normalize uppercase trace IDs in URL (#3477) #3493

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samar-703 force-pushed the fix/uppercase-traceId-normalization branch from 662a70f to 606a720 Compare February 6, 2026 15:07

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samar-703 added 5 commits March 7, 2026 05:29

test: added integration test for tracePage uppercase to lowercase tra…

edb1b4c

…ce ID normalization Signed-off-by: Samar <hello.samar7@gmail.com>

fix: addressed all copilot suggestions

7180889

Signed-off-by: Samar <hello.samar7@gmail.com>

refactor: use React namespace for useEffect in useNormalizeTraceId

9097997

Signed-off-by: Samar <hello.samar7@gmail.com>

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yurishkuro changed the title ~~fix: normalize uppercase trace ids to lowercase in URL~~ fix: Normalize uppercase trace ids to lowercase in URL Mar 9, 2026

yurishkuro merged commit 863cbe8 into jaegertracing:main Mar 9, 2026
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thc1006 mentioned this pull request Mar 9, 2026

refactor: convert TracePage from class to functional component #3435

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samar-703 commented Jan 31, 2026

Which problem is this PR solving?

Description of the changes

How was this change tested?

Checklist

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Review

Summary

What's Good

Issues & Suggestions

1. Bug: location in useEffect dependency causes infinite loop risk

2. Bug: getUrl mock in tests doesn't match real signature

3. Potential double-fetch still exists

4. ensureTraceFetched lost the early return

5. Test weakened for TracePageImpl

6. Minor: getLocation is now unused

7. Copyright year

Verdict

codecov bot commented Mar 7, 2026 •

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1. Bug: `location` in useEffect dependency causes infinite loop risk

2. Bug: `getUrl` mock in tests doesn't match real signature

4. `ensureTraceFetched` lost the early return

5. Test weakened for `TracePageImpl`

6. Minor: `getLocation` is now unused

1. Bug: `location` in useEffect dependency causes infinite loop risk

2. Bug: `getUrl` mock in tests doesn't match real signature

4. `ensureTraceFetched` lost the early return

5. Test weakened for `TracePageImpl`

6. Minor: `getLocation` is now unused