Add support for dynamic index in OpenSearch exporter

[ps48]

Support for Dynamic Log Indexing in OpenSearch

This PR supports dynamic log index names using placeholders in the logs_index config. You can use any attribute or context key as a placeholder to construct index names dynamically per log record.

logs_index

• Placeholder: %{key}

  • Example: otel-logs-%{service.name} or otel-logs-%{custom.label}
  • The value is looked up from a context map (resource attributes, log attributes, etc.).
  • If the key is missing, the value from logs_index_fallback is used (or unknown if not set).

• If logs_index is not set, the exporter will use the default naming pattern: ss4o_{type}-{dataset}-{namespace} (e.g., ss4o_logs-default-namespace). This ensures backward compatibility and a predictable index naming scheme.

logs_index_time_format

You can append a time-formatted suffix to the index name using the logs_index_time_format option.

• logs_index_time_format: If set, appends a time suffix to the resolved index name using the specified format (default is no suffix).
• Valid tokens (case-sensitive):
  • yyyy (4-digit year)
  • yy (2-digit year)
  • MM (2-digit month)
  • dd (2-digit day)
  • HH (2-digit hour, 24h)
  • mm (2-digit minute)
  • ss (2-digit second)
• Allowed separators: -, ., _, +
• Examples:
  • yyyy.MM.dd → 2024.06.07
  • yyyy-MM → 2024-06
  • yyMMdd → 240607
  • yyyy_MM_dd+HH → 2024_06_07+15
• Any other characters or tokens will result in a configuration error.

Link to tracking issue

#34746
#38595

Testing

Unit tests for parsing and rendering logs_index, logs_index_fallback, and logs_index_time_format. Integration tests against a local OpenSearch instance to verify index names (including fallbacks and timestamp formatting).

Documentation

Updated exporter/opensearchexporter/README.md

Example Configuration

exporters:
  opensearch:
    http:
      endpoint: http://opensearch.example.com:9200
    logs_index: "otel-logs-%{service.name}"
    logs_index_fallback: "default-service" # optional, if not set default is `unknown`
    logs_index_time_format: "yyyy.MM.dd" # optional, if set appends time suffix

[andrzej-stencel]

Looks good, just minor non-blocking comments.

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: ps48 / name: Shenoy Pratik (01eb19f, da30968, cffac7e, 682c6a9, 42e46c4, 346f05a)
• ✅ login: paulstn / name: Paul Sebastian (98d618d)
• ✅ login: andrzej-stencel / name: Andrzej Stencel (4501f34, 4d80c8b)

[ps48]

Hi @andrzej-stencel, Thanks for review. We have made the abovementioned changes in this PR. Can you please take a look and help us merge this PR? Thanks again!

[songy23]

Generated code is out of date, please run "make generate" and commit the changes in this PR.

[KarstenSchnitter]

Thanks for providing this feature. I think the documentation can be improved as can be the performance impact in case the feature is not used.

[KarstenSchnitter]

Can it be more than 2 attributes or placeholders for this message to be used?

[ps48]

I see the message is not clear. Changed this to logs_index can only have one placeholder. 346f05a

[KarstenSchnitter]

Can you not do that, if no LogsIndex is set? You do not need the data structure in that case.

[ps48]

Great catch. updated this line and moved it only if the logs_index config is set: 346f05a

[ps48]

Generated code is out of date, please run "make generate" and commit the changes in this PR.

Thanks @songy23 updated the autogen file here: 682c6a9

[ps48]

Hi @andrzej-stencel @KarstenSchnitter, Please let me know if there are any other changes needed here. Thanks!