Remove deprecated code about reporting metrics in single csv file

enterprise/metrics/src/docs/ops/metrics.asciidoc

@@ -69,7 +69,6 @@ For storing metrics in local CSV files add the following settings to _neo4j.prop
 ----
 metrics.csv.enabled=true // default is 'false'
 metrics.csv.path=<file or directory path, defaults to "metrics/" in the store directory>
-metrics.csv.file=<single/split, if split then each metric gets its own file in given directory>
 metrics.csv.interval=<how often to store data, defaults to 3s>
 ----
 

enterprise/metrics/src/main/java/org/neo4j/metrics/MetricsSettings.java

@@ -35,12 +35,6 @@
 @Description( "Metrics settings" )
 public class MetricsSettings
 {
-    public enum CsvFile
-    {
-        single, // Use a single file for all metrics, with one metric per column
-        split // Use one file per metric
-    }
-
     // Common settings
     @Description( "A common prefix for the reported metrics field names. By default, this is either be 'neo4j', " +
                   "or a computed value based on the cluster and instance names, when running in an HA configuration." )
@@ -97,20 +91,11 @@ public enum CsvFile
     // CSV settings
     @Description( "Set to `true` to enable exporting metrics to CSV files" )
     public static Setting<Boolean> csvEnabled = setting( "metrics.csv.enabled", Settings.BOOLEAN, Settings.FALSE );
-    @Description( "The target location of the CSV files. Depending on the metrics.csv.file setting, this is either " +
-                  "the path to an individual CSV file, that have each of the reported metrics fields as columns, or " +
-                  "it is a path to a directory wherein a CSV file per reported field will be written. Relative paths " +
-                  "will be intepreted relative to the configured Neo4j store directory." )
+    @Description( "The target location of the CSV files: a path to a directory wherein a CSV file per reported " +
+                  "field  will be written. Relative paths will be interpreted relative to the configured Neo4j " +
+                  "store directory." )
     public static Setting<File> csvPath = setting( "metrics.csv.path", Settings.PATH, Settings.NO_DEFAULT );
 
-    @Deprecated
-    @Obsoleted( "This setting will be removed in the next major release." )
-    @Description( "Write to a single CSV file or to multiple files. " +
-                  "Set to `single` (the default) for reporting the metrics in a single CSV file (given by " +
-                  "metrics.csv.path), with a column per metrics field. Or set to `split` to produce a CSV file for " +
-                  "each metrics field, in a directory given by metrics.csv.path." )
-    public static Setting<CsvFile> csvFile = setting(
-            "metrics.csv.file", Settings.options( CsvFile.class ), CsvFile.single.name() );
     @Description( "The reporting interval for the CSV files. That is, how often new rows with numbers are appended to " +
                   "the CSV files." )
     public static Setting<Long> csvInterval = setting( "metrics.csv.interval", Settings.DURATION, "3s" );

enterprise/metrics/src/main/java/org/neo4j/metrics/output/CsvOutput.java

@@ -32,7 +32,6 @@
 import org.neo4j.kernel.impl.spi.KernelContext;
 import org.neo4j.kernel.lifecycle.LifecycleAdapter;
 import org.neo4j.logging.Log;
-import org.neo4j.metrics.MetricsSettings;
 
 import static org.neo4j.kernel.configuration.Config.absoluteFileOrRelativeTo;
 import static org.neo4j.metrics.MetricsSettings.csvEnabled;
@@ -46,7 +45,7 @@ public class CsvOutput extends LifecycleAdapter
     private final Log logger;
     private final KernelContext kernelContext;
     private ScheduledReporter csvReporter;
-    private File outputFile;
+    private File outputPath;
 
     public CsvOutput( Config config, MetricRegistry registry, Log logger, KernelContext kernelContext )
     {
@@ -66,29 +65,14 @@ public void init()
             if ( configuredPath == null )
             {
                 throw new IllegalArgumentException( csvPath.name() + " configuration is required since " +
-                        csvEnabled.name() + " is enabled" );
-            }
-            outputFile = absoluteFileOrRelativeTo( kernelContext.storeDir(), configuredPath );
-            MetricsSettings.CsvFile csvFile = config.get( MetricsSettings.csvFile );
-            switch ( csvFile )
-            {
-            case single:
-                csvReporter = CsvReporterSingle.forRegistry( registry )
-                        .convertRatesTo( TimeUnit.SECONDS )
-                        .convertDurationsTo( TimeUnit.MILLISECONDS )
-                        .filter( MetricFilter.ALL )
-                        .build( outputFile );
-                break;
-            case split:
-                csvReporter = CsvReporter.forRegistry( registry )
-                        .convertRatesTo( TimeUnit.SECONDS )
-                        .convertDurationsTo( TimeUnit.MILLISECONDS )
-                        .filter( MetricFilter.ALL )
-                        .build( ensureDirectoryExists( outputFile ) );
-                break;
-            default: throw new IllegalArgumentException(
-                    "Unsupported " + MetricsSettings.csvFile.name() + " setting: " + csvFile );
+                                                    csvEnabled.name() + " is enabled" );
             }
+            outputPath = absoluteFileOrRelativeTo( kernelContext.storeDir(), configuredPath );
+            csvReporter = CsvReporter.forRegistry( registry )
+                    .convertRatesTo( TimeUnit.SECONDS )
+                    .convertDurationsTo( TimeUnit.MILLISECONDS )
+                    .filter( MetricFilter.ALL )
+                    .build( ensureDirectoryExists( outputPath ) );
         }
     }
 
@@ -117,7 +101,7 @@ public void start()
         if ( csvReporter != null )
         {
             csvReporter.start( config.get( csvInterval ), TimeUnit.MILLISECONDS );
-            logger.info( "Sending metrics to CSV file at " + outputFile );
+            logger.info( "Sending metrics to CSV file at " + outputPath );
         }
     }