Add enum processor to map string 'state' field to int

Change-Id: Ice94f6543aa0d8f638ba31e5a775e2ca26f3e206
diff --git a/mongodb/meta/telegraf.yml b/mongodb/meta/telegraf.yml
index ea60745..159677f 100644
--- a/mongodb/meta/telegraf.yml
+++ b/mongodb/meta/telegraf.yml
@@ -3,4 +3,22 @@
 agent:
   input:
     mongodb:
+  processor:
+    enum:
+      namepass: "mongodb"
+      mapping:
+        - field: "state"
+          default: -1
+          value_mappings:
+            # https://docs.mongodb.com/v2.6/reference/replica-states/
+            STARTUP: 0
+            PRIMARY: 1
+            SECONDARY: 2
+            RECOVERING: 3
+            STARTUP2: 5
+            UNKNOWN: 6
+            ARBITER: 7
+            DOWN: 8
+            ROLLBACK: 9
+            REMOVED: 10
 {%- endif %}