What

TableConf.engineConf() previously returned an empty map, so file-system options a customer sets as table options (e.g. fs.s3a.access.key, fs.azure.account.key.<acct>.dfs.core.windows.net) never reached the Hadoop Configuration that AbstractKernelTable builds for the Delta Kernel engine.

This change copies every customer-provided key prefixed with fs. into engineConf(), mirroring the prefix-filter pattern already used by catalogConf().

public Map<String, String> engineConf() {
  return raw.entrySet().stream()
      .filter(entry -> entry.getKey().startsWith("fs."))
      .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue));
}

Precedence

In AbstractKernelTable.createEngine() these options are applied:

• after the built-in fs.* defaults → customer values override the defaults
• before vended credentials → credentials still win on collision

The apply order is unchanged.

Tests

New TableConfTest covers:

• all fs.* keys are forwarded
• non-fs. keys (delta.*, io.unitycatalog.*, checkpoint.frequency) are excluded
• empty result when no fs.* keys are present
• keys added later via update(...) are picked up

Validation (per flink/skills.md)

• build/sbt "flink / javafmt" — clean, no changes
• build/sbt "flink / Test / javafmt" — clean, no changes
• build/sbt "flink / test" — 202 total, 0 failed, 198 passed, 4 skipped
• build/sbt "flink / Compile / doc" — success

Note

This forwards all fs.* options verbatim, including any secrets a customer supplies as table options. That is consistent with how the built-in defaults and vended credentials already flow into the engine Configuration.

Tracking: #5901

This pull request and its description were written by Isaac.