Update changelog and readme for logging changes (prometheus-community#945)

sysadmind · rtkkroland · commit e3e0dbd0bbee · 2025-01-24T10:34:50.000-05:00
- Update README to include section about configuring the logging settings. - Update CHANGELOG with information about breaking changes in the logging output from prometheus-community#942. Signed-off-by: Joe Adams <github@joeadams.io>
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -4,7 +4,10 @@ BREAKING CHANGES:
 
 The flag `--es.slm` has been renamed to `--collector.slm`.
 
-* [CHANGE] Rename --es.slm to --collector.slm #XXX
+The logging system has been replaced with log/slog from the stdlib. This change is being made across the prometheus ecosystem. The logging output has changed, but the messages and levels remain the same. The `ts` label for the timestamp has bewen replaced with `time`, the accuracy is less, and the timezone is not forced to UTC. The `caller` field has been replaced by the `source` field, which now includes the full path to the source file. The `level` field now exposes the log level in capital letters.
+
+* [CHANGE] Rename --es.slm to --collector.slm #932
+* [CHANGE] Replace logging system #942
 
 ## 1.8.0 / 2024-09-14
 
diff --git a/README.md b/README.md
@@ -50,7 +50,7 @@ elasticsearch_exporter --help
 
 | Argument                | Introduced in Version | Description                                                                                                                                                                                                                                                                                                                                                                           | Default     |
 | ----------------------- | --------------------- |---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| ----------- |
-| collector.clustersettings| 1.6.0                | If true, query stats for cluster settings (As of v1.6.0, this flag has replaced "es.cluster_settings").                                                                                                                                                                                                                                                                                | false |   
+| collector.clustersettings| 1.6.0                | If true, query stats for cluster settings (As of v1.6.0, this flag has replaced "es.cluster_settings").                                                                                                                                                                                                                                                                                | false |
 | es.uri                  | 1.0.2                 | Address (host and port) of the Elasticsearch node we should connect to. This could be a local node (`localhost:9200`, for instance), or the address of a remote Elasticsearch server. When basic auth is needed, specify as: `<proto>://<user>:<password>@<host>:<port>`. E.G., `http://admin:pass@localhost:9200`. Special characters in the user credentials need to be URL-encoded. | <http://localhost:9200> |
 | es.all                  | 1.0.2                 | If true, query stats for all nodes in the cluster, rather than just the node we connect to.                                                                                                                                                                                                                                                                                           | false |
 | es.indices              | 1.0.2                 | If true, query stats for all indices in the cluster.                                                                                                                                                                                                                                                                                                                                  | false |
@@ -78,6 +78,10 @@ For versions greater than `1.1.0rc1`, commandline parameters are specified with
 
 The API key used to connect can be set with the `ES_API_KEY` environment variable.
 
+#### Logging
+
+Logging by the exporter is handled by the `log/slog` package. The output format can be customized with the `--log.format` flag which defaults to logfmt. The log level can be set with the `--log.level` flag which defaults to info. The output can be set to either stdout (default) or stderr with the `--log.output` flag.
+
 #### Elasticsearch 7.x security privileges
 
 Username and password can be passed either directly in the URI or through the `ES_USERNAME` and `ES_PASSWORD` environment variables.
