From 74debccf057cf5bebff2fd7af692f657d6f1b1c2 Mon Sep 17 00:00:00 2001
From: Dimitar Nanov <dimitar.nanov@ecollect.net>
Date: Tue, 2 Oct 2018 13:25:59 +0300
Subject: [PATCH] add positon mapping option to event

---
 README.md     |  5 ++++-
 lib/domain.js | 15 +++++++++++----
 2 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/README.md b/README.md
index 0ac01fe..eda8f94 100644
--- a/README.md
+++ b/README.md
@@ -405,7 +405,10 @@ The values describes the path to that property in the event message.
 	  meta: 'meta',
 
 	  // optional, if defined the commit date of the eventstore will be saved in this value
-	  commitStamp: 'commitStamp'
+	  commitStamp: 'commitStamp',
+
+	  // optional, if defined and the eventstore db implemntation supports this the position of the event in the eventstore will be saved in this value
+	  position: 'position'
 	});
 
 
diff --git a/lib/domain.js b/lib/domain.js
index bbd269c..45e51b0 100644
--- a/lib/domain.js
+++ b/lib/domain.js
@@ -214,10 +214,17 @@ _.extend(Domain.prototype, {
 
     this.definitions.event = _.defaults(definition, this.definitions.event);
 
-    if (this.definitions.event.commitStamp) {
-      this.eventStore.defineEventMappings({
-        commitStamp: this.definitions.event.commitStamp
-      });
+    if (this.definitions.event.commitStamp || this.definitions.event.position) {
+      var mappings = {};
+      if (this.definitions.event.commitStamp) {
+        mappings.commitStamp = this.definitions.event.commitStamp;
+      }
+
+      if (this.definitions.event.position) {
+        mappings.position = this.definitions.event.position;
+      }
+
+      this.eventStore.defineEventMappings(mappings);
     }
     return this;
   },