Fix flaky test in FirestoreConvertersTest caused by nondeterministic Json message

[LucaDai]

Fix Issue: https://github.com/GoogleCloudPlatform/DataflowTemplates/issues/2901 Similar fix before: https://github.com/GoogleCloudPlatform/DataflowTemplates/pull/1176

Root Cause

The flaky behavior was detected by NonDex when running com.google.cloud.teleport.v2.utils.FirestoreConvertersTest.

This test originally compared JSON strings directly using strict string equality inside PAssert.that(...).containsInAnyOrder(expectedErrors).

However, the generated JSON strings were created through serialization of objects such as ErrorMessage and EntityJsonPrinter, which internally rely on non-deterministic field ordering in Map implementations (e.g., HashMap) during JSON construction. Because of this, the same logical JSON data could appear in different field orders across runs:

Run 1: {"message":"Datastore Entity Without Key","stacktrace":null,"data":"{\"properties\":{\"street\":{\"stringValue\":\"Some street\"},\"number\":{\"integerValue\":\"1\"}}}"}
Run 2: {"data":"{\"properties\":{\"street\":{\"stringValue\":\"Some street\"},\"number\":{\"integerValue\":\"1\"}}}","message":"Datastore Entity Without Key","stacktrace":null}
}

Since the test asserted equality on the raw string representation, it failed whenever the JSON fields appeared in a different order, even though the logical content was identical.

This issue is not specific to NonDex—it indicates the test’s sensitivity to iteration order during JSON serialization.

Fix

Update the test to compare the semantic JSON content instead of relying on string order: • Parse both the actual and expected JSON strings using JsonParser.parseString(...). • Compare them as structured JSON objects (JsonObject), ensuring equivalence regardless of key ordering. • Keep PAssert.that(...).satisfies(...) to validate all outputs while allowing flexible order matching. This fix ensures deterministic validation across JVM runs and environments while preserving full logical equivalence of JSON data.

[gemini-code-assist[bot]]

Summary of Changes

Hello @LucaDai, I'm Gemini Code Assist[^1]! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request resolves a persistent flakiness issue in the FirestoreConvertersTest suite. The problem stemmed from tests directly comparing JSON strings, which could vary in field order due to non-deterministic serialization. The solution involves enhancing the test logic to perform semantic JSON comparisons, ensuring that the tests validate the actual data content rather than its incidental string representation. This change significantly improves test reliability and stability.

Highlights

• Flaky Test Fix: Addressed a persistent flaky test in FirestoreConvertersTest that was failing due to non-deterministic JSON field ordering during serialization, even when the logical content was identical.
• Semantic JSON Comparison: Updated test assertions to compare JSON content semantically by parsing strings into JsonObjects, ensuring tests pass regardless of the order of fields within the JSON.
• Dependency Update: Introduced com.google.gson.JsonParser to facilitate robust JSON parsing within the test suite, enabling object-level comparison.

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[LucaDai]

/gemini review

[LucaDai]

/gemini review

[codecov[bot]]

Codecov Report

:white_check_mark: All modified and coverable lines are covered by tests. :white_check_mark: Project coverage is 50.04%. Comparing base (87c6fe9) to head (a537295). :warning: Report is 12 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #2902      +/-   ##
============================================
- Coverage     50.07%   50.04%   -0.04%     
- Complexity     4969     4970       +1     
============================================
  Files           967      967              
  Lines         59298    59329      +31     
  Branches       6441     6448       +7     
============================================
- Hits          29693    29690       -3     
- Misses        27501    27532      +31     
- Partials       2104     2107       +3     

Components	Coverage Δ
spanner-templates	70.44% <ø> (-0.06%)	:arrow_down:
spanner-import-export	68.93% <ø> (-0.16%)	:arrow_down:
spanner-live-forward-migration	79.69% <ø> (ø)
spanner-live-reverse-replication	77.42% <ø> (ø)
spanner-bulk-migration	88.21% <ø> (ø)
see 8 files with indirect coverage changes

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[LucaDai]

Hi @Abacn, Thanks for labeling this PR! 🙏 I've fixed the spotless issue. Could you please also help review it (or assign the right reviewer) when you have time?