[Index Management] Report the index mode Elasticsearch returns for data streams

[kapral18]

Closes #283371

Summary

• Data streams whose backing indices use index.mode: time_series (or lookup, vectordb_document) showed Standard in the Data Streams list and in the details flyout, or LogsDB for logs-*-* names on clusters with logsdb enabled. They now show the mode Elasticsearch reports.

Root Cause

• deserializeDataStream only let logsdb and standard through; every other index_mode went through the logs-* LogsDB inference and otherwise fell back to standard. The allow-list arrived with [Index management] Introduce data stream lifecycle editing #275740, replacing the pass-through from [Index Management] Display index mode of data streams depending on logsdb.enabled cluster setting #207131; the narrowing was not called out there.

Fix

• Accept any known IndexMode value from the Get Data Streams API. The logs-* → LogsDB inference still applies only when Elasticsearch reports no mode or an unknown one.
• Unit tests cover the pass-through and the preserved fallbacks.
• Unskipped the Scout test "allows to downgrade data stream from logsdb to time series index mode".
• The serverless data streams API test reads the expected index mode from Elasticsearch instead of hardcoding standard: vectordb projects default data streams to vectordb_document, which the API now reports.

Before/After Screenshots

Data Streams list, Index mode column for a time series data stream:

Before:

After:

Data stream details flyout, Index mode:

Before:

After:

Test Plan

1. In Dev Tools Console, create a time series template and data stream:

   PUT _index_template/test
   { "index_patterns": ["test-*"], "data_stream": {}, "template": { "settings": { "index.mode": "time_series", "index.routing_path": "host" }, "mappings": { "properties": { "host": { "type": "keyword", "time_series_dimension": true } } } } }
   PUT _data_stream/test-stream
   

2. Open Stack Management → Index Management → Data Streams.
3. Expected: the Index mode column for test-stream reads Time series.
4. Click test-stream.
5. Expected: the flyout Index mode row reads Time series.

Release Note

Fixes the Index Management data streams list and details flyout reporting "Standard" for time series data streams.

Assisted with Claude Code using Claude Fable 5.1

🤖 Generated with Claude Code

[infra-vault-gh-plugin-prod]

Pinging @elastic/kibana-management (Team:Kibana Management)

[mattkime]

Code changes look good and work well!

[kibanamachine]

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• Commit: c1610bc
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Metrics [docs]

✅ unchanged

History

• 💛 Build #500730 was flaky 4b58cf7
• 💚 Build #499841 succeeded 9523d78