!189 Audit log documentation and fixes

Merge pull request !189 from jessica-surya/audit-log-fixes

hetu-docs/en/admin/audit-log.md

@@ -0,0 +1,46 @@
+# Audit Log
+
+openLooKeng audit logging functionality is a custom event listener that is invoked for query creation and query completion (success or failure)
+An audit log contains the following information:
+
+1. time when an event occurs
+2. user ID
+3. address or identifier of the access initiator
+4. event type (operation)
+5. name of accessed resource
+6. result of an event
+
+In an openLooKeng cluster, only a single event listener plugin can be active at a time.
+
+## Implementation
+
+Audit logging is an implementation of `io.prestosql.spi.eventlistener.EventListener` in `HetuListener` plugin. Methods overwritten include `AuditEventLogger#onQueryCreatedEvent`
+and `AuditEventLogger#onQueryCompletedEvent`
+
+## Configuration
+To enable audit logging feature, the following configs must be present in `etc/event-listener.config` for this feature to be active.
+
+```
+hetu.event.listener.type=AUDIT
+hetu.event.listener.listen.query.creation=true
+hetu.event.listener.listen.query.completion=true
+```
+
+Other audit logging properties include: 
+`hetu.event.listener.audit.file`: Optional Property to define absolute file path for the audit file. Ensure the process running the openLooKeng server has write access to this directory.
+
+`hetu.event.listener.audit.filecount`: Optional property to define the number of files to use
+
+`hetu.event.listener.audit.limit`: Optional property to define the maximum number of bytes to write to any one file
+
+Example configuration file:
+
+``` properties
+event-listener.name=hetu-listener
+hetu.event.listener.type=AUDIT
+hetu.event.listener.listen.query.creation=true
+hetu.event.listener.listen.query.completion=true
+hetu.event.listener.audit.file=/var/log/hetu/hetu-audit.log
+hetu.event.listener.audit.filecount=1
+hetu.event.listener.audit.limit=100000
+```

hetu-listener/src/main/java/io/hetu/core/eventlistener/HetuEventListenerConfig.java

@@ -192,7 +192,7 @@ public class HetuEventListenerConfig
      */
     @Config("hetu.event.listener.audit.file")
     @ConfigDescription(
-            "Optional property to define absolute file path for the logger. If not set, logger will use the default "
+            "Optional property to define absolute file path for the audit logger. If not set, audit logger will use the default "
                     + "log file")
     public HetuEventListenerConfig setAuditFile(String auditFile)
     {

presto-main/etc/event-listener.properties

@@ -2,10 +2,9 @@ event-listener.name=hetu-listener
 hetu.event.listener.type=AUDIT
 hetu.event.listener.listen.query.creation=true
 hetu.event.listener.listen.query.completion=true
-hetu.event.listener.listen.split.completion=true
 #hetu.event.listener.logger.file=/tmp/hetu-events.log
 #hetu.event.listener.logger.count=1
 #hetu.event.listener.logger.limit=0
-hetu.event.listener.audit.file=/tmp/hetu-audit.log
+hetu.event.listener.audit.file=/var/log/hetu/hetu-audit.log
 hetu.event.listener.audit.filecount=1
-hetu.event.listener.audit.limit=0
+hetu.event.listener.audit.limit=100000