[Logs UI] Remove scaling and pre-aggregation in datafeed (elastic#44268)

This simplifies the datafeed configuration by removing the date histogram aggregation and the bucket script, that scaled the document count. It also adjusts the chart's y axis label accordingly.

Additionally it adds a `job_revision` metadata item to the job config that we can use to detect outdated job configs in the future in order to prompt the user to reinstall new jobs.

x-pack/legacy/plugins/infra/public/containers/logs/log_analysis/api/ml_setup_module_api.ts

@@ -51,35 +51,7 @@ export const callSetupMlModuleAPI = async (
             },
           },
         ],
-        datafeedOverrides: [
-          {
-            job_id: 'log-entry-rate',
-            aggregations: {
-              buckets: {
-                date_histogram: {
-                  field: timeField,
-                  fixed_interval: `${bucketSpan}ms`,
-                },
-                aggregations: {
-                  [timeField]: {
-                    max: {
-                      field: `${timeField}`,
-                    },
-                  },
-                  doc_count_per_minute: {
-                    bucket_script: {
-                      script: {
-                        params: {
-                          bucket_span_in_ms: bucketSpan,
-                        },
-                      },
-                    },
-                  },
-                },
-              },
-            },
-          },
-        ],
+        datafeedOverrides: [],
       })
     ),
   });

x-pack/legacy/plugins/infra/public/pages/logs/analysis/sections/log_rate/chart.tsx

@@ -93,7 +93,7 @@ export const ChartView = ({ data, timeRange }: Props) => {
           <Axis
             id={getAxisId('values')}
             title={i18n.translate('xpack.infra.logs.analysis.logRateSectionYaxisTitle', {
-              defaultMessage: 'Log entries per minute',
+              defaultMessage: 'Log entries per 15 minutes',
             })}
             position="left"
             tickFormat={value => Number(value).toFixed(0)}
@@ -128,7 +128,7 @@ export const ChartView = ({ data, timeRange }: Props) => {
           <LineSeries
             id={lineSpecId}
             name={i18n.translate('xpack.infra.logs.analysis.logRateSectionLineSeriesName', {
-              defaultMessage: 'Log entries (avg)',
+              defaultMessage: 'Log entries per 15 minutes (avg)',
             })}
             xScaleType="time"
             yScaleType="linear"

x-pack/legacy/plugins/ml/server/models/data_recognizer/modules/logs_ui_analysis/ml/datafeed_log_entry_rate.json

@@ -1,28 +1,4 @@
 {
   "job_id": "JOB_ID",
-  "indexes": ["INDEX_PATTERN_NAME"],
-  "aggregations": {
-    "buckets": {
-      "date_histogram": {
-        "field": "@timestamp",
-        "fixed_interval": "900000ms"
-      },
-      "aggregations": {
-        "doc_count_per_minute": {
-          "bucket_script": {
-            "buckets_path": {
-              "doc_count": "_count"
-            },
-            "script": {
-              "lang": "painless",
-              "params": {
-                "bucket_span_in_ms": 900000
-              },
-              "source": "60 * 1000 * params.doc_count / params.bucket_span_in_ms"
-            }
-          }
-        }
-      }
-    }
-  }
+  "indexes": ["INDEX_PATTERN_NAME"]
 }

x-pack/legacy/plugins/ml/server/models/data_recognizer/modules/logs_ui_analysis/ml/log_entry_rate.json

@@ -4,7 +4,6 @@
   "groups": ["logs-ui"],
   "analysis_config": {
     "bucket_span": "15m",
-    "summary_count_field_name": "doc_count_per_minute",
     "detectors": [
       {
         "detector_description": "count",
@@ -25,6 +24,7 @@
     "enabled": true
   },
   "custom_settings": {
-    "created_by": "ml-module-logs-ui-analysis"
+    "created_by": "ml-module-logs-ui-analysis",
+    "job_revision": 1
   }
 }