Sample GES Projection That "Unrolls" NES Commit

NES Commit

{
  "BucketId": "b",
  "StreamId": "1b42e222-92d6-4242-a528-53a8e61fa524",
  "StreamRevision": 2,
  "CommitId": "0b7efcaa-9923-4813-a780-380fb23ad04a",
  "CommitSequence": 1,
  "CommitStamp": "2014-08-18T15:36:43.5386215Z",
  "Headers": {
    "A header": "A string value",
    "Another header": 2
  },
  "Events": {
    "$type": "System.Collections.ObjectModel.Collection`1[[NEventStore.EventMessage, NEventStore]], mscorlib",
    "$values": [
      {
        "Headers": {},
        "Body": {
          "$type": "NEventStore.Persistence.AcceptanceTests.ExtensionMethods+SomeDomainEvent, NEventStore.Persistence.AcceptanceTests",
          "SomeProperty": "Test"
        }
      },
      {
        "Headers": {},
        "Body": {
          "$type": "NEventStore.Persistence.AcceptanceTests.ExtensionMethods+SomeDomainEvent, NEventStore.Persistence.AcceptanceTests",
          "SomeProperty": "Test2"
        }
      }
    ]
  }
}

Output Stream

// EventType: ExtensionMethods+SomeDomainEvent, Position: 1
{
  "$type": "NEventStore.Persistence.AcceptanceTests.ExtensionMethods+SomeDomainEvent, NEventStore.Persistence.AcceptanceTests",
  "SomeProperty": "Test2"
}
// EventType: ExtensionMethods+SomeDomainEvent, Position: 0
{
  "$type": "NEventStore.Persistence.AcceptanceTests.ExtensionMethods+SomeDomainEvent, NEventStore.Persistence.AcceptanceTests",
  "SomeProperty": "Test"
}

Projection

fromStream("$et-NEventStoreCommit")
.partitionBy(function(e){
	return e.body.BucketId + "-" + e.body.StreamId;
})
.when({
	NEventStoreCommit: function(s, e) {
		if (!e.body || !e.body.Events) return;
		var events = e.body.Events.$values || e.body.Events || [];
		for (var i=0; i < events.length; i++) {
			var eventMessage = events[i];
			var data = eventMessage.Body;
			var metadata = eventMessage.Headers;
			
			var clrType = data.$type;
			
			if (!clrType) return;
			
			var fullTypeName = clrType.split(",")[0];
			
			var type = fullTypeName.split(".").pop();
			
			if (!type) return;
			
			emit("flattened-" + e.body.BucketId + "." + e.body.StreamId, type, data, metadata);
		}
	}
})