[FLINK-40148][common] Fix TableIdRouter producing wrong sink table for multi-digit source suffix

[sd4324530]

What is the purpose of this pull request?

Fix TableIdRouter.resolveReplacement so it routes tables correctly when the source-table regex contains a multi-character capturing group (e.g. a multi-digit suffix like 13, 14, 16) regardless of whether the sink-table uses a $N back-reference.

Previously, with a rule such as:

route:
  - source-table: db_6.table_([1-9]|1[0-6])
    sink-table:   new_db_6.table_merged

db_6.table_13 was wrongly routed to new_db_6.table_merged3 (and similarly _14 → ...merged4, _16 → ...merged6). The bug was caused by Matcher.find() + Matcher.replaceAll in resolveReplacement: find() only matched the prefix db_6.table_1 (because the alternation [1-9] wins over 1[0-6] for input 13), and replaceAll left the trailing 3 appended to the configured sink-table. Tables 1-9 were unaffected because the regex consumed the entire single-digit suffix.

Brief change log

• Replace Matcher.find() + Matcher.replaceAll(sinkTable) with Matcher.matches() + Matcher.appendReplacement / Matcher.appendTail in TableIdRouter.resolveReplacement. This guarantees the whole source table id is consumed before the substitution is applied, so trailing characters can no longer leak into the sink-table name.
• Add testRouteWithoutBackReferenceWithMultiDigitSuffix and testRouteWithBackReferenceAndMultiDigitCapture to TableIdRouterTest as regression coverage for this bug.

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Verifying this change

This change added tests and can be verified as follows:

• Added unit tests in flink-cdc-runtime/src/test/java/org/apache/flink/cdc/common/route/TableIdRouterTest.java:
  • testRouteWithoutBackReferenceWithMultiDigitSuffix — reproduces the originally reported scenario (sink-table without $1, multi-digit source suffix); fails on master, passes with the fix.
  • testRouteWithBackReferenceAndMultiDigitCapture — guards the same root cause for the $1 back-reference case to prevent future regressions.
• All 12 tests in TableIdRouterTest pass, together with the 7 tests in TableIdRouterMatchModeTest and the 8 tests in SchemaDerivatorTest (27 tests total, no regressions).
• Manually verified by running the failing test against unmodified master: the new test reproduces wrong sink-table names such as new_db_6.table_merged0, ...merged1, ...merged3, ...merged4, ...merged5, ...merged6, which match the issue's report.

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Was generative AI tooling used to co-author this PR?

• Yes

Generated-by: cluade code with minimax m3

[Copilot]

Pull request overview

Fixes TableIdRouter.resolveReplacement to avoid incorrect sink table names when routing rules use regex capturing groups that can match multi-character suffixes (e.g., 13, 14, 16). This aligns the replacement logic with the router’s full-string match semantics and adds regression tests to prevent recurrence.

Changes:

• Switch replacement logic from Matcher.find() + replaceAll(...) to Matcher.matches() + appendReplacement/appendTail to ensure the full source table id is consumed before substitution.
• Add regression tests covering both “no back-reference” and “$1 back-reference” sink-table configurations for multi-digit suffix captures.

Reviewed changes

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

File	Description
flink-cdc-common/src/main/java/org/apache/flink/cdc/common/route/TableIdRouter.java	Fix replacement logic to avoid trailing-character leakage into sink table names for multi-digit regex captures.
flink-cdc-runtime/src/test/java/org/apache/flink/cdc/common/route/TableIdRouterTest.java	Add regression tests reproducing the bug and validating correct routing with/without $1 back-references.

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